A Group Memorandum John M. Lind CPCU ARM 26 Janauary 2022


To: Whom it may concern  

From: John M. Lind CPCU ARM  

Date: 26 January 2022  

Subject: Contaminated air in airliner cabins, A summary but comprehensive presentation  

Ladies / Gentlemen:  

Call it what we may, the FAA Reauthorization Act of 2018, Sensors, Section 326(d) in context with  contaminated cabin air is made necessary by the failure of the RITE/ACER/COE congressionally mandated  program. RITE ACER offered very little knowledge useful to understanding this most illusive occupational  and public health hazard. Illusive, but fundamentally very simply understood, it continues to be a case of  industry cover-up. If anyone would doubt this statement, ask:  

(1) Who is responsible to the people to know and understand the hazards arising from public service  operations?  

(2) What is their responsibility for the cost of accidents and incidents incurred by employees and  passengers during commercial operations?  

(3) Are they fulfilling their obligation?  

(4) The FAA does not investigate fume incidents even though some “incidents” have been fatal. Why  not?  

(5) Why after 40 years has the airline industry failed to solve the contaminated cabin air problem?  Cover up? The questions answer themselves!  

 During the active ACER program, 2004 to 2014, air carrier executives did their collective best to control  opportunity and dialog around this federal mandate. They controlled access to aircraft, chose the aircraft  that could be evaluated, denied investigation on revenue flights, delayed supporting activities, and  somehow, budgeted funding didn’t arrive when and where it was needed. Eventually, in pure pork barrel  fashion, politicians usurped funds for their own pet projects at home.  

How will the industry respond now to the requirements demanded by Section 326(d)?  Truth . . . . as it is intended to apply to this discussion is the truth as I have come to see it.  

  1. The Airline Deregulation Act of 1978 – S-2493, 95th Congress.  

You may have heard this before so I’ll be brief – Into the 1970s, government lawmakers grew more  and more intolerant of high airfares that priced most of society out of air travel. The excesses of the  Civil Aeronautics Board, regulator of all things necessary to air operations, had outlived its industry protective usefulness. Carelessly, the U.S. Congress passed the Airline Deregulation Act of 1978. (1) 

In doing so it forced upon airline managers an 18th century, poorly understood (or deliberately  misrepresented), impractical theory of economics. (2) The expected aggressive competition began and  continued for decades. Fares fell to operationally unsustainable levels leading to excessive cost cutting.  Airline economics turned upside down as expenses fell to meet revenue. Employees were denied  statutory workers compensation; (3) new aircraft and engine maintenance protocols became assurances  that high costs of engine overhauls and bearing seal replacement could safely be avoided.(4)  

Executives now emphasize engine and APU degradation and remaining useful life (RUL). Thus, in  some cases, old, run out engines and APUs become throw away items. Even problem aircraft are  thrown away, reference B-767 N251AY, which is rumored to have burned at the gate in another land. 


  1. The Air Travel Experience – systemic deterioration in air transportation services.  Fifteen to twenty years of industry attrition and decay followed S-2493. Bankruptcies, mergers,  acquisitions, hostile takeovers drove the industry to the brink of disaster. Passenger load factors  increased and revenue fell, customer services were re-invented from complimentary into profit centers.  Uncertainties (5) such as fuel prices, weather, maintenance imperatives, security, changing demand, and  operating adjustments had to be endured under liquidity crises where the generous revenue structure  under CAB rule once carried these burdens effortlessly.  

With demand for seats ever climbing and surviving fleets expanding, the need to push aircraft  utilization to new limits dominated the day. Creeping equipment deterioration occurred. Maintenance  shortcuts ended or delayed necessary repairs. Aircraft with aging engines and APUs continued in  revenue service. Gradually over the period from 1985 to the present, incidents of cabin air  contamination grew. Auxiliary power units in tail cones high off the tarmac required maintenance  platforms for access. They were often overlooked. Some of the worst cases of crew and passenger  disability are attributed to the APU. Engine compressor bearing seals, a recognized source of engine oil  “consumption”, which were regularly replaced before deregulation, have long exceeded their useful  lives.  

The most dangerous consequence of this systemic deterioration was increased incidents of smoke  and fumes causing increased numbers of aircrew and passenger illnesses. Executives and regulators  have ignored their safety and health responsibilities; these dangers remain with us today.  

Major Unintended Consequences:  

Deregulation wasn’t a mistake; some say necessary. It was a poorly conducted process of  inducement to bring more business into the air transportation industry. Instead of planning a  gradual weaning-off from micro-regulations, air carriers were abandoned to “slug each other  senseless” for survival. (6) 

 Deregulation rendered the airline industry unaccountable to all authority, state, Federal, and  public opinion, except the FAA. Grossly, underfunded and poorly guided, the FAA is incapable  of exercising its Congress-delegated authority.  

 Cost cutting to extremes has created a system of constant whack-a-mole to try to keep ahead  of recurring uncertainties and the costs thereof.  

 Prevention in equipment maintenance and employee safety is now but a recollection from the  past among the few who might remember.  

 On-the-job injuries that had been a predictable routine in the airline industry, today are  grossed up by the unanticipated aerotoxic syndrome casualties. Statistics were comprehensive  and accurate! Once upon a time the OJI’s were carefully recorded, marshaled for claimant  indemnification, combed for loss control frequency and severity, shared with NCCI for rate  making, and the National Safety Council for industrial ranking. All of that was my responsibility.  Today most or all of it has been trashed by the airline industry.  

 Carrier executives no longer comply with state workers compensation laws because they know  the historical frequency and severity of accidents brought financial losses unserviceable in the  mandated, low airfare, oversight-poor environment that is by definition, deregulation in a free  marketplace.  

III. Question. Is the contaminated cabin air issue the result of a faulty product?  I once thought the engine bleed air system was a faulty product, a product design defect. As a  former aircraft products liability insurance underwriter (as well as workers comp), and having now had  time to study the aerotoxic situation thoroughly, I am not so sure.  

Powerplant designers, engineers, and manufacturers at the beginning of the jet age were designing  for a revolutionary world of never before seen fast and high-flying aircraft. Previously, passenger  aircraft would struggle to fly over mountain ranges at the lowest levels of the troposphere. Later piston powered aircraft like the Boeing Stratocruiser and the Lockheed Constellation needed engine-driven  superchargers to maintain sufficient combustion air for high altitude operation. These superchargers  also offered enough excess compressed air for the cabins of these aircraft. Jet engines do not use  superchargers. For jet travel then, designers would need a new design for routine flight where  pressurized air would always be essential for air traveler comfort and survival.  

Engine designers and engineers, however, were well aware of the possibility that engine oil could  bypass oil seals at the engine bearing sumps. They soon decided that using engine bleed air as their  basic resource for cabin pressurization and life sustaining oxygen was too much of a worry to  contemplate.(7) Boeing produced its first production jet-liner, the 707, using clean outside air. Their  design used bleed air to drive a turbo compressor (similar in principle to the supercharger) to compress  and condition air for the aircraft interior. McDonald Douglas with the DC-8 and Convair, the 880, would  follow with similar basic designs.  

These aircraft needed four engines to assure thrust sufficient to sustain adequate performance in  this new environment. Even so, they were underpowered. Just why designers, engineers, and  manufacturers so soon abandoned the original clean air philosophy is not specifically explained in the  literature. We must surmise:  

  1. a) Air inlets feeding fresh air to turbocompressors created aerodynamic drag;  
  2. b) Turbo-compressors added weight, hence drag.  
  3. c) Turbo-compressors are an additional maintenance and cost burden.  
  4. d) Rapidly evolving state-of-the-art designs created low and high bypass turbofan engines that  produced an excess of thrust and compressed air.  
  5. e) Inflation required financial reconsideration of cost benefits of equipment and wages.  f) The Boeing 787 style electric generator-driven bleed free compressor system creates power loss at  the gearbox-driven generators in addition to costs mentioned above.  
  6. g) Both engines on the Boeing 787 have three generators – two for primary electrical demand and  redundancy. The third is dedicated to driving the turbocompressor. If a B-787 engine should be lost  during high altitude climb and cruise, one engine could not alone carry the additional demand for  pressurization. The aircraft would be forced to descend.  
  7. h) Weight of the entire bleed air system and its components is removed by this system, the VSFG –  variable frequency starter generator. (8)

These and any other possible burdens that increase flight duration, burn fuel, add maintenance, or  in any way force deviations from regular operations so as to increase operating costs will be financially  unacceptable to airline executives.  

We note, therefore, that airline management is cost-driven – first, last, and always. They must  operate on this basis. Manufacturers are challenged to meet this airline-imposed financial barrier and  compete in the marketplace accordingly. Isn’t it easy to see that research, development, and  manufacturing of the airline aircraft and powerplant product have now evolved to the point of near  perfection? Can it be that the small percentage of imperfection, partly represented by leaky bearing  seals, might be a current state-of-the-art limitation rather than a faulty design or manufacture?  

  1. Our history with sensors  

Advocates for aerotoxic casualties have asked engine manufacturers to repair or replace turbofan  engine bearing seals. The effort to do so leads to the practical decision that once engine disassembly is  needed to replace the seals, a complete engine overhaul will become beneficial. The cost at this point,  as high as $3,000,000, is prohibitive to the overhauler’s and manufacturer’s customer.  

Advocates have also asked aircraft manufacturers to install air sensors in the cabin or oil leak  sensors in engines and ducting. One specific response from an engine manufacturer states, “We will not  put anything on an aircraft that is not ordered by the customer”.  

Today constant monitoring of aircraft in operation around the world provides detailed, sensor-recorded degradation data on turbofan engines. (9) Engines can operate for 10 to 20 years or more  without major maintenance. Air carrier executives now depend upon actual data showing low engine  degradation rates and related useful life (RUL) of engines to permit on-wing continuous operations for  up to a not unusual 50,000 hours. (10)  


With all of the detailed engine monitoring, there are no sensors installed for the purpose of  monitoring cabin air contaminants, not in the air, nor in the engines or ECS ducting. Installing such  sensors to advise pilots when they need to make emergency landings and also advise of necessary  maintenance would erase the cost saving benefits of the entire preventive maintenance protocol. No  matter that aircraft become non-airworthy. No matter that flight attendants become permanently  disabled from carbon monoxide poisoning; pilots and passengers too. No matter that this scenario has  influenced non-compliance with state workers compensation laws. No matter that the airline industry,  writ large, has become a swamp of financial fraud perpetrated for employer financial benefit at the  expense of the innocent flight attendant, pilot, and unsuspecting passenger.  

Forced into the deregulation corner . . .  

This is the air transportation norm of operations today.  

We anticipate sensor data confirming contamination in airliner cabins. Will the 117th Congress  begin a process that will offset the folly of the 95th Congress? Will the results of compliance with  Section 326(d) influence seal replacement? Will new designs result that will remove or mitigate the  toxic fumes from airliner cabins? As air carriers recover from the scourge of a crippling pandemic will  they have mood or desire to be rid of toxic cabin air? Or will they retreat into their tortoise shells of  unaccountability?  

Ill, injured, and disabled crewmembers and their advocates place themselves in positions to see  that the best interests in human health and flying safety are practiced. After four decades of the  international conspiracy of silence about contaminated cabin air, the traveling public deserves no less.  


(1) (a) S.2493, The Act – . . . . to encourage, develop, and attain an air transportation system which relies on competitive market  forces to determine quality, variety, and price of air services . . . .  

(b) CAB Closing – “Now they are on their own. Free markets and private industry do a better job than the Federal  Government.”  


(2) https://corporatefinanceinstitute.com/resources/knowledge/economics/what-is-invisible-hand/  (3) Reports from crewmember testimony, the media, medical records. Cases of wrongfully denied workers compensation.  Undeniable cases of fraud made possible by contracts between employer and claims service companies that in a regulated  environment would be prosecuted as illegal purposes. To be assembled when needed to support purposeful action.  (4) Preventive Maintenance – https://www.sae.org/standards/content/arp1587b/ 

(5) Uncertainty-in-Airline-Revenue-Management.pdf  

(6) Hard Landing, Thomas Petzinger, Jr. Pg. 86 – “a naïve public establishment with the promise of low airfares if only Washington  would force the airlines to compete. The airlines . . . . were dragged kicking and screaming into the coliseum, where, like clumsy  gladiators, they aimlessly slugged each other senseless. Only when it was too late did Congress grasp its folly.” (7) (a) 1953-0560.pdf, Comet Engineering, Air conditioning, 4th paragraph. Attached.  

(b) http://www.bleedfree.eu/wp-content/uploads/2015/10/Reddall-1955-elimination-of-engine-bleed-air-small.pdf  (c) https://scholar.smu.edu/cgi/viewcontent.cgi?article=1405&context=jalc  

(8) Aircraft Powerplants, Wild & Kroes, 8th Edition, Page 410.  

(9) (a) https://medium.com/@hamalyas_/jet-engine-remaining-useful-life-rul-prediction-a8989d52f194   (b) https://www.nasa.gov/collection-asset/chetan-kulkarni-and-external-partners-release-new-turbofan-engine-degradation-0  (c) https://publications.aston.ac.uk/id/eprint/43441/1/2021124272.pdf  

(10) https://www.reuters.com/article/us-air-show-engines-idUSBRE95F0F220130616 

Statement of Truth 10 January 2022

To whom it may concern. 

It has been long accepted and admitted that compressed air from jet engines has been  contaminated with engine oil which contains many harmful chemicals including VOC’s  and Organophosphate substances which are universally accepted to be harmful to  health with well-known symptoms. 

The UK Government has been aware and discussing the problem for a number of years  whilst the vast majority of the public and medical profession remain completely  unaware of scale and extent of the problem.  

As a result of 27 pilots’ blood and fat being tested in March – May of 2006 with  associated memory and cognitive function tests carried out at the same time by UCL  (University College London) it has revealed shocking and incontrovertible evidence that  there is a serious health hazard for anybody who flies in these aeroplanes; especially the  crews and is therefore a serious flight safety issue. The report will be available from  May 22nd 2006, but may be restricted in its distribution for obvious reasons. 

Other people that have also been at risk are the entire Royal family and senior members  of the Government who have flown on the BAe 146 for the last twenty years and cannot have escaped the same contamination. 

The BAe 146 and Boeing 757 are well known for being the worst offenders of  commercial airliners, possibly due to sharing a similar make of APU or Auxiliary Power  Unit and its use on the ground. 

There have been many incidents and fatal accidents attributed to ‘fatigue’ and ‘pilot  error’ on the BAe 146 and B. 757 over the years but never any suggestion that  contaminated air is fundamentally to blame. 

I wish to make it clear that due to intense covering up of the phenomenon over the past  ten years or more it is now my duty to point out that any accident in the future should  be regarded as probably being caused by this effect and for any suggestion that it is not  a factor to be subject of a criminal enquiry and manslaughter charges for those people  denying the link. 

Statement by: 

John Grahame Hoyte 

22nd May 2006. 

………………………………………………………………………………………………… Past: 

My previous Statement was written on 22 May 2006 and is now updated as a result of new  evidence. 

At the time, I was sure that I had discovered a cause of mass public ill health, with little to do  with medicine, science and all to do with money – public health is claimed as paramount.

On 18 June 2007, I launched the Aerotoxic Association Ltd. www.aerotoxic.org at the  Houses of Parliament, London having founded the association as a Limited Company ‘The  Charity’ on 19 March 2007. https://aerotoxic.org/memorandum-of-association-of-aerotoxic association-ltd-the-charity/ 

Present at the launch were Captain Tristan Loraine, Dr Susan Michaelis, Captain Julian  Soddy (formerly of BALPA – British Airline Pilot Association) and other aircrew, plus  Samantha Sabatino – a passenger.  

LHS John Hoyte, Susan Michaelis with paper, Tristan Loraine with tin, Julian Soddy RHS. 

The launch was covered by The Daily Telegraph 24 June 2007: Pilots disabled by poisoned  air: https://aerotoxic.org/wp-content/uploads/2020/11/Christopher-Bookers-notebook Telegraph-1.pdf 

The term Aerotoxic Syndrome was first published on 20 October 1999  https://aerotoxic.org/wp-content/uploads/2021/04/Balouet-et-al-1999.pdf by US Flight  surgeon Dr Harry Hoffman, forensic scientist Dr Jean Christophe Balouet of France and toxicologist Professor Chris Winder of Australia as a result of their research throughout the  1990’s. 

I was unaware of the term in my previous Statement, as Capt. Loraine first introduced it to  me in June 2006. The chronology of this ‘story’ is essential throughout: Who knew which evidence and when. 

More recently, the UK government and aviation lawyers have referred to the public disease  as ‘Aerotoxic Poisoning’ https://aerotoxic.org/wp-content/uploads/2020/11/mp-fiona-bruce 30th-june-2019.pdf or ‘Aerotoxicity’ or ‘Aero Toxic’. 

WHO published an updated report in 2017: “AEROTOXIC SYNDROME: A NEW  OCCUPATIONAL DISEASE?”. 


Since 2006, I have met and been contacted by countless other members of the public from  around the world who have had their health adversely affected by flying in ‘Bleed air’ jets https://www.youtube.com/watch?v=ETRZDsgjEvE that comprise all jets, with the sole 

exception of the Boeing 787 Dreamliner, which does not use bleed air architecture for cabin  air.  

In this Statement, as a cross section of survivors, I cite three different examples of evidence  over the past 16 years of 1) A former RAF test Pilot 2) A group (40) of Passengers and  3) A former Cabin Crew – flying in different countries and in different types of jet aircraft. 

  1. Captain Julian Soddy, a former RAF and BAe 146 pilot and campaigner who has  appeared in many documentaries since 2004 including a BBC Panorama ‘Something  in the air’ shown on 21 April 2008. His evidence was in the House of Lords 2007  Science & Technology Report. Captain Soddy of Norfolk, UK chaired the BALPA (British Airline Pilot Association) Cabin Air Quality London conference of 20/21  April 2005:  

https://www.anstageslicht.de/fileadmin/user_upload/Geschichten/Aerotoxisches_Synd rom/BALPA-CAPC-London-2005_WINDER.pdf & https://vimeo.com/11111751 

  1. A group of 40 unrelated passengers (including young children) of Flight XLA 120 on  1 February 2007 led by Samantha Sabatino flying from London Gatwick, UK to  Sanford International, Florida, US also gave evidence to the House of Lords in 2007, appeared in a 2007 documentary ‘Welcome Aboard Toxic Airlines’, BBC Panorama of  2008, ‘Toxic Flyer’ 60 Minutes ABC Australia in 2013 & Stewarts Law of London  represented them until 2012. 

Aerotoxic Poisoning 

3 May 2010 

The Stewarts Law Attorney Group represents 20 British passengers who were  seriously injured by aircraft toxic fumes exposure on 1 February 2007. The incident  occurred when they were flying onboard an XL Airways Boeing 767 from London  Gatwick to Sanford International, Florida. 

The dangerous toxins were released into the cabin through the bleed air system  which (as on most airliners) draws high-pressure air from the core of the engines to  pressurise the aircraft with breathable air. It has long been known that this design  can result in the cabin air becoming contaminated with toxic oil vapour when the  engine oil seals leak. 

Passengers detected the toxic air as they began to notice an odd smell similar to  ‘smelly socks’. The cabin seemed more ‘stuffy’ and ‘hot’ than any previous flight  they had been on, and the air severely irritated their eyes, nose and throat. The  

passengers quickly became ill, suffering respiratory issues, severe headaches,  vomiting, bowel problems, skin blistering and extreme fatigue. The toxic air also  caused them to experience long term / chronic effects such as respiratory problems,  memory loss, sleep disturbances, chronic fatigue, mood swings, cognitive  difficulties, infections, and joint/limb pains. 

To put pressure on the US manufacturers to deal with these known cabin air  problems and to obtain fair compensation for the passengers, on 29 January 2009  specialist litigation firm Stewart’s Law filed the case in Illinois, the state where  Boeing has its Headquarters. In addition to ‘Boeing’, the lawsuit was filed against 

‘Hamilton Sundstrand’ (manufacturers of air systems components), ‘United  Technologies’ (manufacturers of the Pratt & Whitney engines) and the owners of  the aircraft – ‘AAR Parts Trading Inc’. 

This case is an outright US product liability case against US defendants. However,  the defendants were intent on having the case sent back to the UK courts (which are  much more expensive for claimants and award much lower compensation). They  filed a forum non-conveniens motion, arguing that the UK is the most convenient  place for the litigation. 

After the prolonged legal battle, on 3 May 2010 Judge Quinn decided in favour of  the passengers and dismissed the defendants’ forum non-conveniens motion.  Stewart’s Law has achieved a great victory for the passengers. Securing US  jurisdiction along with the prospect of a high profile jury trial is a wake up call for  US manufacturers – unless they take measures to improve the quality of cabin air  now, they will face the credible prospect of expensive and public US litigation for  future incidents where there is an identifiable toxic fumes leak that causes injury. 

A large group of unrelated passengers (which may include doctors,scientists and politicians etc) becoming acutely and chronically sick on the same flight is crucial to demonstrate that  anyone can be made sick on any flight as they ‘pay to fly’ and that both aircrew and  passengers are genuinely ill and do not have the so-called ‘Nocebo effect’ or ‘hyperventilation’ https://www.caa.co.uk/Passengers/Before-you-fly/Am-I-fit-to fly/Guidance-for-health-professionals/Aircraft-fume-events/ as often claimed by some  ‘doctors’:  

***Both Captain Soddy and the XLA 120 passenger evidence may all be viewed at the  following: http://www.unfiltered.vip/flight-xla 

120.html?fbclid=IwAR3azXQTD2aes1OthhXQr1mXbBG8lJ2yaduzmupegmhke1WV5X7j9 yHDBH4 

  1. Evelyn van den Heuvel – formerly a cabin crew of KLM and The Netherlands who  began flying aged 23 in 2006 – flew for only three years and is now permanently  injured and harmed for life and she finally won her public court case in June 2021.  “I want aerotoxic syndrome to become a recognized disease. I wasn’t aware of it. Now I’m a wreck”. Another legal precedent for countless others:  

https://www.tubantia.nl/binnenland/ex-stewardess-strijdt-tegen-giftige-lucht-in cabine-ik-ben-een-wrak~af6e3cef/ & https://youtu.be/P94i7_eM13A 

After understanding the cause of mass public ill health in early 2006, I attended the first  meeting of the Global Cabin Air Quality Executive (GCAQE) https://www.gcaqe.org/ on the 5 October 2006.  

I have attended each of 15 annual conferences of GCAQE since including the online  conference 15-18 March 2021. https://www.gcaqe.org/webinars 

A key expert witness over the past 20 years has been Dr Sarah Mackenzie Ross of University  College London (UCL) who attended the BALPA conference of 2005, attended the first  GCAQE meeting of 2006 and continues to work on and research this public health issue. https://www.sarahmackenzieross.com/

During the last half of 2021, I have hosted regular weekly ‘A’ Team Friday meetings on  Zoom which includes former US aviation insurance Expert with an aerotoxic injured flight  attendant daughter; a former General Practitioner; a Professor – expert in sensor technology and aerotoxic syndrome; an expert witness aviation Engineer; a former Sub Postmaster who  are all unaffected by aerotoxic syndrome and several past and present aircrew. 

We have, as an expert team, published in mid 2021 a novel engineering solution in a  recognized journal for avoiding contaminated air in the future. 

BBC – coverage of CAQ (Cabin Air Quality) over the past 17 years has been disappointing  given that the illness can affect anyone who flies as evidenced by the BBC Panorama  coverage of a large passenger group in 2008 and is usually only broadcast on regional  programmes or the World Service in the small hours of the morning.  

In 2009, I contacted the BBC to cover new published research and a Radio 4 Today  programme was broadcast on 24 September 2009. Detailed evidence may be seen in my  personal diaries (which I kept from 17 October 2006 to 23 July 2013) of other members of  the public who contacted me following the broadcast and I am still in touch with today.  http://news.bbc.co.uk/today/hi/today/newsid_8270000/8270978.stm 

In 2015, I was interviewed live by the BBC in Norwich about the legal case of Richard  Westgate, a former BA pilot, who had first contacted the Aerotoxic Association on 16 March  2012 and died on 12 December 2012. On the way to the studio, I was told by the BBC that I  could appear but must not mention either the airlines I had flown for, TNT & Flybe, or the  words ‘Cover-up’. https://www.youtube.com/watch?v=zGVL1N4LZYM 

It has been frustrating recently that the BBC have not kept the public informed about public  court wins and published science with the absence of any open public debate which is now  blocking formal medical recognition and the known/available solutions from introduction. 

The latest BBC coverage was on 25 February 2020 https://www.bbc.co.uk/news/stories 51633897 and it is known that the 260 UK aircrew legal cases will finally begin from March  2022, and the British public and BBC licence fee payers are in for a shock. 

After years of gathering evidence, 10 lead cases against four UK airlines are due at the  Royal Courts of Justice this year. Unite, the union behind the action, says it wants the public  to know about the aviation industry’s biggest secret. “An extraordinary amount of powerful  evidence has been gathered,” says General Secretary Howard Beckett. “The simple reality for us is that our members are at risk from low-level exposure, and it is a  simple reality that frequent fliers will also be at risk as a result,” he told me.” 

Over the past two years particularly, new evidence has been sent to the BBC, but the public appear to being kept in the dark. Aerotoxic appears to be a taboo and banned word. 

Oxford Neuroscience  

As a result of a chance meeting in May 2021 with a senior research Doctor of Oxford  University Neuroscience https://www.neuroscience.ox.ac.uk/ it was hoped that their interest  in ‘further research’ work might take place, but this was before a key peer reviewed paper  was published, the Dutch public court win and ACES of late 2021 – so no further interest  resulted.

Dr David Megson 

Just before the premature death of Dr Jean Christophe Balouet on 31 March 2021, he put me  in touch with Dr David Megson of Manchester University who explained that a new ‘peer  reviewed’ scientific paper would be published later in 2021. 

This paper Occupational risk of organophosphates and other chemical and radiative  exposure in the aircraft cabin: A systematic review” was finally published in July 2021: https://aerotoxic.org/wp-content/uploads/2021/09/Hayes-et-al-aerotox-review.pdf 

It was particularly frustrating that this key peer reviewed published paper was not shared with  the public by the BBC and other media with the public as of public interest, however the  paper has since been sent to and acknowledged by the Business Manager to the Chair and  Chief Executive of the UK Civil Aviation Authority on 17 December 2021. 


Recent key evidence from the US includes: The Aerotoxic Association was contacted by  Attorney John Martin of KJC Law in Boston in early October 2020 and based on my help now advertises to represent injured parties (aircrew or passengers). 


& Blog https://www.massachusettsinjurylawyer-blog.com/the-secret-risks-of-flying aerotoxic-syndrome-explained/ 

There are around 10 other US law companies advertising for new clients – Google ‘Toxic  Cabin Air’: https://www.schmidtlaw.com/aerotoxic-syndrome-lawsuit/ 

In July 2020, a key legal case of Captain Andrew Myers was won in the US: https://48b4ed48-471d-4786-b5ed 


US Attorney’s piece for the Myer’s case: https://48b4ed48-471d-4786-b5ed b7d9563b03f8.filesusr.com/ugd/3e3e4e_6488a47ee0ac40a6b0f06fc1101d2fed.pdf 

The LA Times reported on 17 December 2020 about Toxic Cabin Air ‘We are slowly being  poisoned’. This article focused on the reasoning behind the absence of toxic air sensors: https://www.latimes.com/projects/toxic-chemicals-planes-covid-19-travel-woes/ “Senior Boeing engineers worried that data from sensors would prove damaging in  lawsuits by sick passengers and crew members”. 

In 2021, Teledyne of the US announced the first Toxic Air Sensor – Aircraft Cabin  Environment Sensor (ACES) which has been approved for the Boeing 737 and Airbus A320  but is able to be used in any bleed air jet aircraft. 


In Teledyne’s White Paper: 

Areas of Controversy: 

Whether deserved or not, bleed air is often the primary target in the cabin air quality  debate, even though typically electric fans and many other cabin items contribute a far  greater number of reported SFO events. One reason is bleed air’s possible role as a conduit  to bringing low levels of engine oil or hydraulic fluid into the cabin, which might be  harmful for people exposed over long periods of time. Suspicion has fallen on engine load bearing seals (see Figure 11) as one source of oil, and compounds such as tricresyl  phosphate, or TCP, in the oil as perhaps responsible for causing harm. Aerotoxic  Syndrome has been proposed as a name for the symptoms seen in some flight crew, but  there remains debate about whether or not it exists.  

It would appear that further open public debate is required to judge whether Aerotoxic  Syndrome does actually exist. 

In 2014, respected aviation journalist David Learmount wrote the following Foreword for my  ‘Pilot Press’ published book Aerotoxic Syndrome – Aviation’s Darkest Secret’  https://aerotoxic.org/wp-content/uploads/2021/06/Aerotoxic-Syndrome-Book-1.pdf 

Aerotoxic syndrome exists. But so does systematic denial by the aviation industry and its  government backers. As an aviation journalist for 35 years at the time of writing this  Foreword, for a long time I believed the industry when it told me, hand on heart, that the  dangers to pilot and passenger health of engine oil fumes entering aircraft cabins were  dramatically exaggerated and very rare. But eventually I agreed to meet two former airline  pilots who had suffered damage and lost their careers to aerotoxic syndrome. I had,  however, met others before and had not been convinced, so what made the difference this  time? Tristan Loraine and Susan Michaelis provided me with the technical data and  evidence of something that had been going on for years – about 50 years. They informed  me about the chemicals involved, the ongoing biochemical research into the damage these  can cause to humans, the fume event occurrences and what makes them happen, and the  human stories of pilots and cabin crew affected. And through them I met a network of  aeromedical specialists and biochemists who were studying the issue in detail. Then I  started asking questions again in the industry, but I was much better informed this time.  No aircraft or aero-engine manufacturer denies that fumes from engine oil can get into  cockpits and cabins, nor do they deny that these ‘fume events’ happen from time to time.  They do not deny either that these engine oils contain organophosphate materials that can  cause neurological damage in humans. The oil containers even have warnings on them to  that effect. The reason the industry and its government backers can keep the lid on this  issue is that the burden of proof about the damage these fumes can cause rests with the  victims. The industry answers charges about health damage by denial and dissembling,  which the system lets them do because of the rules about where the burden of proof lies.  The industry’s lawyers are masters of technical points of law that enable them to claim that  the victims have no legal proof of the connection between Aerotoxic Syndrome a fume  event and the symptoms that the victims suffer as a result. The lawyers can argue that the  cause might lie elsewhere in the victim’s life, or in their metabolism, and this ‘negative’  allegation is very difficult to disprove. There is a precise parallel here between the legal  war fought for years between the tobacco industry and damaged smokers and the medical  world who were looking for the proof of a connection between tobacco smoking and lung  cancer. Everybody knew that there was a connection, but the burden of proof was with the  victims, and until a precise biomarker could establish that the cancer was initiated by the 

effects of tobacco-based chemicals in specific individuals who smoked, the industry could  go on denying. The only difference between these two cases is one of scale. The health  effects of tobacco affected billions of people worldwide, whereas although aircraft fume  events happen regularly, they only occur once every several hundred flights. And when  they do, some individuals are affected while others are not, because of metabolic  differences between individual humans and the frequency of exposure that any individual  suffers. The fact that fewer people are involved makes it easier for the industry and  government to continue the denial, and more difficult for those damaged to seek any form  of redress – or even acknowledgement of their medical condition. It means ordinary  doctors are kept in ignorance of the syndrome and its symptoms, making misdiagnosis  more likely. The fact is that, for those who are affected, the effect of aerotoxic syndrome on  their lives can be devastating. For that reason, it is obscene that the industry washes its  hands of the issue, and even worse that governments collude, because there are ways of  reducing or even eliminating the risk of airborne fume events. But while denial exists and  governments collude with the manufacturers and airlines, these remedies will not be  applied. That is what this book is about.  

David Learmount,  

Operations and safety editor, Flight International 

It is on record that Carbon Monoxide (CO) sensors were used in RAF fighters in 1941 during  WW2 so for sensors to be first available in public transport jets over 80 years later  demonstratesthe averseness for governments and aircraft manufacturers to allow the flying  public to know what is in cabin air. 

Since 2006, much emphasis has been put on organophosphate (OP) chemical exposure being responsible for public ill health, but over the past 20 years OP’s have been downgraded to  ‘irritant’ chemicals rather than ‘deadly’ which was how they were classified when I was an  aerial crop spraying pilot in the 1980’s and few scientists or even specialist aviation doctors  are aware either of the presence of OP’s in jet engine oil as an anti-wear additive or the  illness. 

However, more recently the invisible, odourless, colourless, tasteless, deadly gas of carbon  monoxide (CO) has been suggested as being present in contaminated air in aircraft as this can  cause acute and chronic public ill health symptoms which a well-documented, published  Boeing 727 oil fume event flight of 22 September 1992 with the following acute symptoms  over the first 14 days but the illness has continued chronically for over 25 years for US Flight  Attendant Deanne de Witte Freise: 

In Flight – All four flight attendants reported illness, Passengers reported nausea and  headaches. Symptoms: CNS-anaesthesia, acute respiratory, acute neuromuscular, acute  confusion. 

5 Hours ER: Probable Inhalation Injury Diagnosis Notes: Nausea, headaches, tunnel vision,  legs weak and heavy, fasciculations, back and neck pain, shakes, spasms, abdominal  cramping, needles and tingles, skin burning hot, burning chest, hot flashes, ears, ringing,  joint pain. 

16 Hours ER Record: cognitive problems, disoriented, memory and concentration. disoriented, slurred speech and stammering, headache, nausea, dizziness, blurred vision,  sweating, Carbon Monoxide Level 2.5 

20 Hours Internist Doctor: ataxia, inability to coordinate thumb and finger, inability to  subtract 7 serially from 100, inability to remember 3 digits, Diagnosis: organic brain  syndrome beyond acute anxiety – Toxic Encephalopathy. 

Day 2 Lost sense of humour, Personality gone, Couldn’t match socks, Retarded, Muscle  spasms, Wandering, agitated, angry at forgetfulness, Falling up and down stairs, Balance  gone, Black chemical diarrhoea. 

Day 3 Son found mother could not turn on washing machine- EMTs were called, Neurologist  documents toxic encephalopathy with significant cognitive dysfunction, Organic brain  syndrome, small white rash on face and neck, Weak right lower extremity, Memory loss, Speech disorder. 

Day 5 Reads paper but does not retain anything, Increasing weakness and involvement of  neck muscles and eye muscles, Head falls to the right. 

Day 8 and 9 Increased weakness of arms and legs, Stumbling when walking, Muscle twitches,  Neck pain, Manual dexterity decreased, Fuzzy vision, Hair loss, Cognitive disorientation. Day 10 Neuropsychologist indicated cognitive problems consistent with Toxic  Encephalopathy and recommends specific cognitive remediation. 

Day 14 Unstable, Drift of right arm and leg, Confusion, Visual problems, Headaches, Joint  pain, Using words wrong, Generalized weakness, Difficulty reading because words tend to  jump on the page. 

The 2019 US Cabin Air Safety Act made specific reference to the introduction of CO  monitors: https://www.congress.gov/bill/116th-congress/house-bill/2208/text?r=8&s=1 

Horizon Scan of the Disease Market for 2021 published by BC Legal of Southend listed  aerotoxic Syndrome first: https://www.bc-legal.co.uk/bcdn/1159-319-horizon-scan-of-the disease-market-for-2021 


Despite all previously published evidence since the 1950’s, there is still a claim of ‘no  positive evidence’ of Aerotoxic Syndrome and attempting to communicate with public  authorities who are accountable has become challenging as they generally answer with silence. 

It is also more challenging to know exactly which ‘evidence’ to produce as over the past 17  years as countless members of the public, family and friends have also known about this public health issue and find it equally difficult to know how to handle it or how it will end. 

Therefore, in 2015 I contacted the Norfolk Police to put evidence on the public record and  since then have kept in touch with a Staff Officer who has a record of events and evidence and will be sent a copy of this formally witnessed Public Statement. 

One of the main difficulties that I have encountered has been that my Member of Parliament  since 2015, Clive Lewis of Norwich South, has refused to communicate – not only with me  but other constituents about this ‘campaign’, despite being a Labour party MP and with past  connections to Unite the Union – even though I met him in 2015 and gave him a copy of my  2014 book. 

In frustration, I wrote to the office of HM Queen in 2016 and received a reply and left  Norwich to try and find a more understanding UK MP in March 2021:

https://www.shropshirestar.com/news/local-hubs/oswestry/2021/07/01/pilot-fights-for aerotoxic-syndrome-to-be-officially-recognised/ 

The Guardian covered the issue on 19 August 2017: ‘There are hundreds of sick crew’ is  toxic air on planes making frequent flyers ill? 

https://www.theguardian.com/science/2017/aug/19/sick-crew-toxic-air-planes-frequent flyers-ill 

Unite the Union’s 2020 position on toxic cabin air: https://www.unitetheunion.org/news events/news/2020/february/airlines-must-stop-buck-passing-and-take-immediate-action-on toxic-air/ 

Previously, I and the Aerotoxic Association had excellent representation from 2007 to 2010  from John Maples MP, which is all recorded. 

https://publications.parliament.uk/pa/cm200809/cmhansrd/cm090701/halltext/90701h0006.ht m 

Since then,several MP’s have become aware of the public health issue including Henry  Smith MP who called for a debate in 2015: 


2016 House of Commons Aerotoxic Syndrome debate:  

https://publications.parliament.uk/pa/cm201516/cmhansrd/cm160317/halltext/160317h0001. htm 

Since 2006, there has been a large amount of ‘peer reviewed’ international research into  Aerotoxic Poisoning yet after each study ‘Further research’ is recommended.  

To date, chemical contaminants such as CO have been identified but still the levels or doses  in a visible oil fume event have not been openly published and no researcher has ever yet  asked for any evidence from the Aerotoxic Association. 

Nearly 16 years later, I know I have discovered an inconvenient cause of mass public ill  health with deliberately harmful medicine, questionable science, and huge amounts of money. 

I have in recent weeks reasoned that it is best to write an updated formal public Statement of  truth as I am exhausted, embarrassed and have ‘run out of words’ and to then remain silent,  except for attending any public court.


Visible oil fume event accident 5 August 2019  



260 UK legal cases are due to be judged at the UK Royal Courts of Justice from March 2022. 

The 17th annual GCAQE conference will be 14-15 September 2022: 


ACES sensors are already in use by a major US airline and low-cost personal CO data  loggers are available for aircrew and passengers, it is reasoned that it is only a matter of time  before attorneys call for evidence in the form of data which has been recorded – both of the  levels of contaminants present in cabin air and of their duration. 

For example, Carbon Monoxide records will be available in the future from oil fume event  flights such as XLA 120. 

8 January 2022: “Strong Chemical Odor On Alaska Airlines Plane Sends Two Flight  Attendants to the Hospital” 

“So-called ‘smoke, odor, or fume’ events, as they are known in the industry, are sometimes  referred to as ‘toxic fume events’ because of the devastating impact that they can reportedly  have on the short and long term health of those exposed to one”. 

https://www.paddleyourownkanoo.com/2022/01/08/strong-chemical-odor-on-alaska-airlines plane-sends-two-flight-attendants-to-the 

hospital/?fbclid=IwAR3nq0S3pLf_0zyn7DdHR3d8BHwJTVRTnLZREbBHagBlkFVCqrkU UMsvY74

A cost-efficient design change for enhancing the aircraft cabin air supply – Graeme A. Davidson

The PW JT3-3D-powered DC8 did not use engine bleed air for cabin pressurization and air conditioning. It was fitted with two nose “chin scoops”, each of which had three separate intakes (Figure 1). A small amount of engine bleed air was, however, used to spin the turbo compressors (TCs) that drew in and compressed fresh air, raising its temperature in the process. That air then flowed through the two heat exchangers and Freon units for delivery, at controlled temperature, into the cabin pressurization and air distribution system. 

Figure 1. The nose of the DC8. On each side, the large centre opening was the intake for the respective left and right air-to-air heat exchangers; the two smaller holes were individual intakes for the four turbo compressors. 

In later, “advanced” versions of the DC8, the JT3s were replaced with more efficient CFM 56s and the chin scoops were modified to close the TC inlets, the TCs and heat exchangers being replaced with “packs” to use direct engine bleed air for air conditioning and pressurization. At the time that was considered to be progress! 


Bleed air is a term that is frequently discussed when it comes to aircraft systems, particularly when a cabin air

event (“fume event”) is involved, but what exactly is bleed air and what does it do on the aircraft? 

2.1 The Brayton cycle  

The basic operation of the gas turbine is a Brayton cycle with air as the working fluid. Atmospheric air flows through the compressor that brings it to a higher pressure; energy is then added by spraying fuel into the air and igniting it; the combustion generates a high temperature flow. This high-temperature pressurized gas enters a turbine, producing a shaft work output, which is used to drive the compressor; unused energy comes out in the exhaust gases, which can be repurposed for external work, such as directly producing thrust in a turbojet engine, or rotating a second, independent turbine (known as the power turbine) that can be connected to a fan, propeller, or electrical generator. The purpose of the gas turbine determines the design to achieve the most desirable split of energy between the thrust and shaft work. The fourth step of the Brayton cycle (cooling of the working fluid) is omitted, as gas turbines are open systems that do not reuse the same air. 

2.2 So what is bleed air? 

“Bleed air” is the term used for the air that is “bled” from the compressor stages of a gas turbine engine. At this stage the air has a temperature of around 200–250 °C and a medium-high pressure; its energy is used to power several airframe systems, including but not limited to the air conditioning (Figure 2). 

The use of bleed air is common throughout commercial aircraft and helicopters today as it is a readily available source of energy. If the engines work proficiently, bleed air will be available. Its most useful qualities are heat and pressure. Heat is often used for anti-ice and deicing systems and the pressure is used for flow services such as the provision of cabin air. 

* E-mail address for correspondence: g.davidson902@btinternet.com 

Journal of Biological Physics and Chemistry 21 (2021) 35–42 Received 23 February 2021; accepted 30 June 2021 

© 2021 Collegium Basilea & AMSI doi: 10.4024/06DA21R.jbpc.21.02 

36 G.A. Davidson Enhancing aircraft cabin air ______________________________________________________________________________________________________

Figure 2. Schematic diagram of a typical aircraft bleed air system. 

2.3 Anti-ice 

Icing conditions exist both on the ground and whilst airborne in most regions of aircraft operations. Ice accretion can occur between +10 and –50 °C when moisture is present such as in rain or as multimers in a cloud. This water can condense and freeze on the cold wings, especially on their and other leading edges, changing the profile shape and upsetting the lift characteristics designers have so carefully created. 

With the aid of bleed air, the threat of ice accretion and the dangers this brings in flight can be mitigated. There are numerous ways to rid an aircraft of ice, but bleed air is one of the most commonly used methods. 

2.3.1 Anti-ice via air tubes 

By routing hot bleed air via piccolo tubes inside the leading edges of the wings, tail surfaces and the engine inlets, the surfaces can be heated to above freezing temperature. Once the warm air raises the temperature of the surface, any ice already formed melts away and further ice accretion is prevented. This is the most 

common method of ice protection on the majority of commercial aircraft. An exception is the Boeing 787, one of the most efficient aircraft of its size. The aircraft has electrothermal anti-icing for the main leading edges of the wings. This ice protection system is typically seen on lighter aircraft. The use of electrical instead of bleed air helps to decrease fuel burn and improves overall cost efficiency by eliminating the high-maintenance bleed systems albeit with the penalty of the weight of the additional electrical generation equipment required. 

2.3.2 Deicing boots 

Turboprop aircraft such as the Dash 8 Q400 cruise at altitudes below 27,000 ft and spend much time in the heavily moisture-laden cloud zones. These aircraft use what is known as “pneumatic boots” to keep their surfaces ice-free. The “boot” is a layer of rubber placed on the leading edge of the wing that is inflated with bleed air to temporarily change the shape of the wing and break off any unwanted ice.

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Pneumatic boots haven’t changed much in their design since their invention over 80 years ago and are fairly lightweight. Unfortunately they do require regular inspec tion and maintenance. They can crack when operating; the material deteriorates in ambient conditions, especially due to ozone exposure; and they can be punctured by debris from the runway or ice shed from the propellers. 

2.4 Pressurization and air conditioning 

Possibly the most important use of bleed air is to enable cabin pressurization and environmental conditioning (Figure 3). Pressurizing the air within the cabin allows us to breathe at high altitudes without oxygen masks; heating it allows ordinary clothing to be worn. Furthermore, oxygen is consumed by human breathing and must be replenished, and the exhaled carbon dioxide must be removed. Air bled from the engine is a readily available continuous source of fresh, hot pressurized air. 

Figure 3. The use of air bled from the main engine to heat and pressurize the cabin and provide a continuous source of fresh atmospheric oxygen. 

As mentioned, bleed air temperature can be over 250 °C when it leaves the engine and hence must be cooled via a heat exchanger before it can be circulated into the cabin. Cold air from outside the aircraft is used and passes over the hot bleed air in the air cooler. The primary temperature controller is on the flight deck (Figure 2), although many aircraft provide the capability for altering the temperature from inside the cabin. The temperature selector changes the amount of cool air allowed through the air ducts until the desired temperature is reached. 

On twin-engine aircraft, both engines are used to supply conditioned air, although other sources of bleed air are available at various stages of flight. Four-engine aircraft such as the BAE 146/RJ bleed from all four engines. On the ground, many airports in hot locations

provide air through a ground supply, identified by a large yellow pipe when the aircraft is parked on the stand. This provides air conditioning without the need to use the auxiliary power unit (APU), thus keeping noise and emissions low. The APU is more commonly used, however, as external air is not always available. Located at the rear of the aircraft, the APU is a small, low technology engine that works in the same way as the larger main engines, creating its own bleed air. With the main engines switched off this is the independent source of air conditioning. Conversely, the APU is usually idle when the main engines are running. 

2.4.1 Depressurization 

Failure of the bleed air system can lead to cabin depressurization, such as on a recent A319 flight from Cape Town to Johannesburg. The crew received a warning of the failure of engine no 1’s bleed system and took the appropriate corrective actions. Nonetheless the effective cabin altitude began to increase. The crew therefore made an emergency descent according to standard procedures until they reached a safe altitude. At this lower altitude they were then able to start the APU and use it as a source of bleed air to restore cabin pressure, allowing them to continue to their destination. 

2.4.2 Hydraulic system reservoir pressurization 

Bleed air is also useful in conjunction with the hydraulic system. By pressurizing the hydraulic reservoirs, manufacturers are able to prevent cavitation and the damage it causes. Cavitation occurs when fluid volume demand is greater than the amount of fluid being supplied, leading to bubbles. The fomation of bubbles in the hydraulic systems is a very serious matter—it can cause major failures of pumps and motors. When the bubbles implode they erode and damage nearby surfaces. The implosion is a violent process that generates highly localized, large-amplitude shock waves. Pressurizing the reservoirs with bleed air is an effective way of preventing bubble formation within the fluid. 

2.5 Engine start 

For operational and ground safety reasons, turbofan engines are normally started on the pushback from the airport gate prior to taxi; the operation can take 2–3 minutes or more. To do this the aircraft must have an operational APU supplying both electricity and bleed air. (If the APU is unserviceable, the air must be provided externally from a unit on the ground. The APU itself is started using an electric starter motor that runs off the aircraft 115 V electrical system.) 

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When the start sequence is initiated, bleed air is sent from the APU to the accessory gear box, causing the various shafts within the first engine to rotate. This is when the “suck-squeeze-bag-blow” sequence begins. Once combustion within the engine becomes self sustaining the igniters are switched off and engine start is complete. Once this first engine is running, its bleed air can be used to start the second engine—this is known as a cross-bleed start—and the APU can be switched off as it is no longer needed as a source of bleed air. 


As one would expect, various hazards are associated with the use of extremely hot and high-pressure air. One pitfall of the bleed air cabin air system is that any contaminants from the engine are potentially circulated around the cabin. For instance, hot oil may leak from inside the engine seal and bearing locations into the bleed air supply. Depending on seal design, this can be continuous at a very low level (“weeping” seals), or intermittent (e.g., when engine operating parameters suddenly change). Due to the high air temperature, the oil may be pyrolysed (or even oxidized, despite the presence of antioxidants in typical turbine oil formulation). Hence not only oil but also pyrolysed oil can be mixed with the air being fed to the cabin, leading to a burning smell or even smoke entering the cabin if the seals have deteriorated. Furthermore, if the engines have been incorrectly washed during maintenance, residue from the engine cleaning chemicals can also be fed into the cabin via the bleed air. Flight deck and cabin crews are trained to deal with such contamination scenarios appropriately to ensure their safety and that of the passengers, but fume events have raised concerns about the quality of cabin air and the long-term effects it might have on the health of aircrew and frequently flying passengers. 

Thankfully such “fume” incidents are much less frequent on newer aircraft than formerly, due to advanced technology such as new Hydro Pad engine seals and improved HEPA and carbon filters in the cabin air supply system (these filters use layers of glass fibres and activated carbon-based material to remove typically 99.7% of particles within the air, including harmful microbes such as some strains of SARS-CoV-2). Such modifications can be retrofitted to older aircraft as an aid to make flying safe. On the other hand the tendency to replace regular maintenance schedules with on-demand on-wing maintenance and overhauls far less frequent than formerly has tended to counter these advances, not least since replacement of a deteriorated oil seal cannot be accomplished on-wing. Improved filters are only a stop-gap fix to horrendous ongoing issues. Hence, a new 

approach is required that could resolve the problem without major redesign and certification issues. 


Gas turbine engines are classified according to the type of compressors they use. There are three types— centrifugal flow, axial flow, and centrifugal-axial flow. Compression of inlet air is achieved in a centrifugal flow engine by accelerating air outward perpendicular to the longitudinal axis of the machine. The axial flow engine compresses air by a series of rotating and stationary airfoils moving the air parallel to the longitudinal axis. The centrifugal-axial flow design uses both kinds of compressors to achieve the desired compression. 

The path the air takes through the engine and how power is produced determines the type of engine. Four types of gas turbine engines are used to propel and power aircraft. They are the turbojet, turbofan, turboprop, and turboshaft. 

4.1 Turbojet 

The term “turbojet” was initially used to describe any gas turbine engine used in aircraft. As gas turbine technology evolved, other engine types were developed to take the place of the pure turbojet engine, which was first developed in Germany and England prior to World War II and is the simplest of all jet engines. The turbojet engine has problems with noise and fuel consumption in the speed range that airliners fly (around 0.8 Mach). These engines are limited in range and endurance and today are mostly used in military aviation. 

The turbojet engine consists of four sections— compressor, combustion chamber, turbine section and exhaust (Figure 4). The compressor section passes inlet air at a high velocity to the combustion chamber. The combustion chamber contains the fuel inlet and igniters for combustion. The expanding air drives a turbine, which is connected by a shaft to the compressor, sustaining engine operation. The accelerated exhaust gases from the engine provide thrust. The basic operations are: compressing air, igniting the fuel–air mixture, producing power to self-sustain the engine operation, and yielding exhaust for propulsion. 

Advantages of the turbojet engine: 

  • Relatively simple design 
  • Capable of very high speeds 
  • Takes up little space. 

Disadvantages of the turbojet engine: 

  • High fuel consumption 
  • Loud 
  • Poor performance at slow speeds 
  • Limited in range and endurance.

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Figure 4. Idealized turbojet engine. 

4.2 Turbofan 

Turbofans (Figure 5) were developed to combine some of the best features of the turbojet and the turboprop. They are designed to create additional thrust by diverting a secondary airflow around the combustion chamber. This 

type of engine is considerably quieter and has better fuel consumption than the turbojet in the usual commercial speed range. Hence, almost all modern designed and certified airliners use turbofan engines. 

Figure 5. Idealized turbofan engine.

Turbofan engines have a large fan (or set of fans) at the front of the engine that produces about 80% of the thrust. They have more than one shaft in the engine; many are two-shaft engines. Rolls–Royce are the world leader in three-shaft designs, which give a shorter engine length but a slightly heavier dead weight. Multiple shafts are arranged concentrically. 

A spool is a compressor and a shaft and turbine that drives that compressor. Two-shafted engines use two spools; that is, there is a compressor and a turbine that drives it and another compressor and turbine that drives it. In a two-spool (-shaft) engine, there is a low-pressure (LP) spool and a high-pressure (HP) spool: the LP one generally contains the front fan(s) and the turbine stages it takes to drive it (them); the HP one is the HP compressor, shaft, and turbines. The latter makes up the core of the engine, and this is where the combustion section is located (and hence is also referred to as the gas generator). 

Turbofan engines can be low-bypass or high bypass. As can be seen in Figure 5, the air generally driven by the fan does not pass through the core of the engine. The amount of air that is bypassed around the core determines the bypass ratio. For example, an engine with a duct fan moving 100 lb/s and a core flow of 20 lb/s has a bypass ratio of 5:1.  

Some low-bypass turbofan engines are used in speed ranges above 0.8 Mach (military aircraft). These engines use augmenters or afterburners to increase thrust. By adding more fuel nozzles and a flame holder in the exhaust system extra fuel can be sprayed and burned, which can give large increases in thrust for short intervals of time. 

Two different exhaust nozzle designs are used with turbofan engines. The air leaving the front fan can be ducted overboard by a separate fan nozzle, or can be ducted along the outer case of the basic engine to be 

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discharged through the mixed nozzle (core and fan exhaust together). In other words, the fan air is either mixed with the exhaust gases before it is discharged (mixed or common nozzle), or it passes directly to the atmosphere without prior mixing (separate nozzle). 

Advantages of the turbofan engine: 

  • Fuel-efficient 
  • Quieter than turbojets 
  • They look awesome! 

Disadvantages of the turbofan engine: 

  • Heavier than a turbojet 
  • Larger frontal area than a turbojet 
  • Inefficient at very high altitudes. 

Turbofans are the most widely used gas turbine engine for air transport aircraft. The turbofan is a compromise between the good operating efficiency and high thrust capability of a turboprop and the high-speed, high-altitude capability of a turbojet. 


The gas turbines are mounted on the aircraft wing by a pylon or at the rear tail. In the former, the bleed air is ducted from the engine compressor into a cooler matrix that is located in the pylon area. The cooler uses air bled from the fan air and then exhausted overboard after passing throught the matrix. It is this area that has to be considered for a change in application of bleeds without requiring major structural design and functional changes to the environmental control system (ECS) operation and control. In more detail (Figure 6), the initial delivery of bleed air is ducted from the HP compressor/combustor offtake ports via a pressure-reducing valve into the heat exchanger located in the shoulder area of the pylon. The exchanger is connected to a supply of fast-flowing air delivered from the by-pass airflow via a scoop arrangement in the ducting behind the fan assembly (Figure 7); it is finally exhausted over the pylon fairing.1 

Figure 6. Bleed air systems. Upper panel, generic design. Lower panel, the BAE 146/ RJ.1 The arrangements with tail-mounted engines on aircraft such as the Fokker 70/100 or MD90 are similar. 

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Figure 7. Precoolers. The lower panel shows the new assembly being calibrated on a test rig to ensure that this part of system operates and is controllable according to the aircraft maintenance manual requirements. 

The challenge for the aerospace industry is to consider a redesign of this area, namely to in effect reverse the operation of the heat exchanger. By using fan air as the principal source of cabin air in place of the hot internal bleed air, the main source of chemical contamination would be eliminated. The existing bleed air would be used to heat the fan air to the required temperature. This would also lighten some of the loading on the compressor section of the engine, which would therefore run more efficiently. 

There could be concerns that bleeding air from the fan area would reduce the amount of air available to support engine-efficient bypass operation. The engine control system is designed to measure the inlet temperature (T2) and the pressure (P2) at the compressor inlet to the core engine in order to ensure the correct delivery of air mass. The system also measures the pressure in the bypass duct. Hence, the means to 

2 https://www.cleansky.eu/systems-for-green-operations-sgo

measure and control these parameters already exist. The modified cabin pressurization and heating system is expected to fall well within the range under control, hence ensuring adaptation to the modification. 


On 3 June 2016, the Airbus Flight Lab (an A320 aircraft) successfully completed its first flight in Toulouse within “Systems for Green Operations (SGO)”, an integrated technology demonstrator (ITD) organized by the European Union.2 The aim of the flight was to test extensive on-board electrical systems under real conditions. One of these is the electrical environmental control system (E-ECS) developed by Liebherr-Aerospace Toulouse SAS, the Liebherr company’s centre of excellence for air management systems (Figure 8). The E-ECS is a key element of thermal and power management for increasingly electrically powered aircraft. It is equipped 

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with a new type of motorized turbo compressor (50 kW) which enables external air (bleed-free) to be used directly for air conditioning in an integrated approach. Power electronics provide speed control of the compressor and the capability of synergy with other electrical loads to optimize overall electrical power consumption on board 

the aircraft.It should be noted that the engines of this test aircraft are configured for test flying purposes and do not represent an in-service aircraft power plant and the associated operational requirements. The additional loading on the engine core has probably not been quantified. 

Figure 8. The Liebherr electrical ECS.


The use of bypass air for pressurizing the aircraft cabin is a modification of the ECS without major changes to the current primary design.The change requires the engine manufacturer to ensure that the proposed use of bypass air would have little impact on the thrust requirements for engine operation. The reduction in air bled from the core should make the engine more efficient. Hence, even on purely engineering grounds the return on the modest investment involved in reconfiguring the heat exchangers could be favourable. The main benefit is expected to be the elimination of chemical contamination, mainly derived from the engine oil, in the cabin and the concomitant improvement of air quality, especially the eradication of the endemic problem of “fume events” with the often severe effects on the safety of operations and the health of crews and passengers. 


The review part of this paper has been compiled using information derived from a number of published articles and reports and other documents, including training manuals (especially the BAE Systems (Regional Aircraft) training material for the BAE 146/RJ series of aircraft), in the public domain, as well as personal notes and pictures acquired through many years of working in the field.The author especially thanks John Hoyte (former BAE 146 training captain and now chairman of the Aerotoxic Association), who initiated discussions around a change in the use and operation of engine bleed 

and ECS systems; Dr Alex Macdonald who coinitiated and engaged in these discussions; Robin Gibbs (aviation consultant of Aviconsult Ltd) and holder of a valuable archive of knowledge; Tim van Beveren (aviation journalist) for his valuable documentary “Unfiltered Breathed In”; and the archives of the late Norman Wilson (Chief Engineer, Rolls–Royce) for information on twin spool engines and the Dart turboprop. The author thanks Liebherr-Aerospace Toulouse for a press release on the new E-ECS, Airbus for a press release on the Liebherr technology, and Honeywell for the illustrations of the precooler assembly and the bench test (Figure 7). 


Davidson, G.A. Routine mechanical causes of aircraft air supply contamination. J. Biol. Phys. Chem. 14 (2014) 90–93. Flitney, R.K. A description of the types of high speed rotary shaft seals in gas turbine engines and the implications for cabin air quality. J. Biol. Phys. Chem. 14 (2014) 85–89. Lind, J.M. Cabin air safety oversight in the airline industry. J. Biol. Phys. Chem. 21 (2021) 18–22. 

Ramsden, J.J. The scientific adequacy of the present state of knowledge concerning neurotoxins in aircraft cabin air. J. Biol. Phys. Chem. 11 (2011) 152–164. 

Ramsden, J.J. Contaminated aircraft cabin air: aspects of causation and acceptable risk. J. Biol. Phys. Chem. 12 (2012) 56–68. 

Rolls–Royce. The Jet Engine (5th edn). Wiley (2015). Strecker, S. and Hui, H.-W. Bypass Air Scoop for Gas Turbine (US Patent 8,092,153, assigned to Pratt & Whitney Canada Corp.) (2012). 

JBPC Vol. 21 (2021) 

John Hoyte Statement of Truth – 20th August 2018

Statement of Mr John Hoyte of 41 Bracondale, Norwich, Norfolk NR1 2AT. UK.

Para Narrative Notes

1. My date and place of birth is 17 October 1955 Edinburgh,


2. I obtained my Private Pilot’s Licence in 1977 and was

trained by the Norfolk & Norwich Aero Club, RAF

Swanton Morley, Norfolk.


3. My career background and experience is briefly set out below:

1974 – 1977 Measuring North Sea Gas at Phillips Petroleum, Bacton, Norfolk.

1976 – 1979 Training for Private Pilots Licence and flying instructing.

1979 – 1987 Aerial Agricultural & bush fire fighting Pilot, Norfolk, Suffolk, Shropshire, Kenya and South Australia.

1987 – 1989 Air Atlantique. DC. 3’s Marine pollution spraying. Coventry.

Statement of John Hoyte (JGH/H2738/002) 1

1989 – 1998 BAe 146 flying for TNT around Europe, night

time duty caused extreme fatigue.

1998 – 2005 BAe 146 flying for (Jersey European Airways)

Flybe, Daytime flying but change to Low Cost with

continuous chaotic rosters created further exhaustion.

4. Throughout my flying time with Flybe I flew BAe146

aircraft. These are passenger planes with a capacity for

approximately 110 passengers. They have four engines

and an Auxiliary Power Unit (APU). They were first

introduced in September 1981 and are a medium range

passenger aircraft with a range of approximately 1,500

miles. The last of the original BAe146’s was built in

1993. Whilst they are very good planes to fly, they have

a particular known problem of fumes coming into the

cockpit and cabin from the jet engines and APU.


5. This particular design of aircraft (and most other jets flying passengers at present with the exception of the Boeing 787 Dreamliner) pipe unfiltered ‘bleed air’ from the engines for the purpose of providing breathable air for the crew and passengers. As the air passes through engines it will inevitably pick up any substance that is

Statement of John Hoyte (JGH/H2738/002) 2

emitted within the engines, by design.

6. There is a particular problem with the BAe146 in that it is

prone to pumping clearly visible oil smoke and fumes

from the Auxiliary Power Unit (APU) into the cabin,

especially on a ‘Cold Start’ which has been witnessed,

described and reported countless times by professional

aircrew to the manufacturers and authorities.

7. The gas turbine jets which power aircraft require a

particular lubricant which is designed to prolong aircraft

life and tolerate the range of operating temperatures of a

jet engine. One such lubricant is Mobile jet oil II. This

oil contains 3-5% Tricresyl phosphate (TCP). This is an

organophosphate and was originally designed to cause

nerve damage, but in engines it is used as an anti-wear

additive; good for engines but not for humans who are

exposed to high concentrations found in visible oil fumes

or even when no fumes are visible but a ‘Dirty sock’

odour is present in the cabin.


8. This problem has been highlighted over a considerable period of time and investigations have been carried out

Statement of John Hoyte (JGH/H2738/002) 3

into the problem since 1953 when it was first identified.

9. To date the problem has been recently acknowledged by

the UK Civil Aviation Authority as causing acute injury

to humans (which then become ‘patients’) but there is

overwhelming evidence in the public domain that

repeated exposures cause chronic ill health, but still

governments continue to claim that there is ‘No positive


10. In September 2001 I became a Training Captain on the

BAe 146 and was filmed for around 45 minutes making a

presentation to colleagues but was criticised afterwards

for my inability to speak properly and using ‘non words’

– I still have this film, as evidence.

11. All through 2004 I continued to experience increasing

stress and extreme fatigue which finally led me to walk

off a flight just before departure to Salzburg on 29th

August 2004 and ‘Failed safe’ as is the professional duty

of all aircrew.


12. Whilst still flying the BAe 146 in September 2004 I went to see Professor Gordon Turnbull who is a psychiatrist

Statement of John Hoyte (JGH/H2738/002) 4

employed by the CAA. He reassured me that I had taken

the right decision not to fly on 29th August 2004 and

wrote a report to the Company. He told the CAA that I

could continue to fly. At the time Professor Turnbull

was not aware of organophosphate poisoning in the

cockpits of commercial aircraft but he has become aware

of the issue since due to many other aircrew reporting it

to him, including Len Lawrence.

I have recently been in touch with Professor Turnbull

concerning my duty with respect to the Aerotoxic issue.


13. I was off flying from September 2004 to January 2005. I went back to flying at the end of January 2005 and things worked quite well for a while. I was flying four days a week. I received a 25% pay cut which was quite difficult to cope with but nonetheless I had three days not working. At that time, I also joined BALPA (British Airline Pilots Association). BALPA made a 50 minute film about contaminated air in 2005 which featured BAe146 Capt. Julian Soddy and sent copies to all of their members, but I did not watch it at the time, as I didn’t think it concerned me and had no time to watch it. Previously I had been a member of the Independent

Statement of John Hoyte (JGH/H2738/002) 5

Pilots’ Association (IPA) who have been proactive since

2005 over the contaminated air issue.

14. On 30th June 2005 I flew my last flight in a BAe 146 and

was accused afterwards of ‘flying whilst sick’ by my

company, which is illegal.

15. The last part of 2005 was challenging as I felt

permanently intoxicated, stressed and ill but refused to

take Prozac or other anti depressants which were offered

to me by Professor Turnbull as I’m not a depressed type

of person and was concerned at the known side effect

information which are included with the tablets.

My GP also prescribed anti-depressant Citalopram, which

again I refused to take.

I had lost my career at the age of 49 and felt suicidal as

though I had let my family down but didn’t know what

was the fundamental cause of sudden serious ill health,

which had begun in the spring of 1990.


16. In early 2006 I was called by Captain Tristan Loraine of BA & BALPA and asked if I would wish to be involved in the testing of other BALPA pilots investigating toxic

Statement of John Hoyte (JGH/H2738/002) 6

cabin air? – I agreed to do so as I was grounded and had

nothing to do.

Dr Sarah Mackenzie Ross of University College London

tested me and 26 other BALPA pilots for cognition and

our blood and fat, which took several months.

The study was later written up as a UCL published paper

in 2008.

17. On 22nd May 2006 I made an unsworn Statement about

the criminal nature and ‘cover up’ of the contaminated air

issue – ‘To whom it may concern’.

I handed the Statement over to lawyer Tim Olerenshaw

of Leamington Spa for safe keeping in 2007.


18. I have known since 22nd May 2006 that the injuries that I and others have suffered were caused by acute and repeated exposures to organophosphates and other toxins in the cabins of the BAe146 aircraft and other bleed air powered jets (with the exception of the Boeing 787 Dreamliner in which bleed air is not used) and that there is criminal cover up in place.

Statement of John Hoyte (JGH/H2738/002) 7


19. In around June 2006 I became more aware of the term Aerotoxic Syndrome after a phone call from Capt. Tristan Loraine, and the term had first been proposed in 1999 by US physician Dr Harry Hoffman and scientists Dr Jean Christophe Balouet of France (who is still alive and well) and Professor Chris Winder of Australia who had been researching human ill health for many years after oil fume exposures in bleed air jet airliners in their respective countries.

I became aware of evidence about Aerotoxic Syndrome including a London conference sponsored by British Airline Pilot Association on 20th and 21st April 2005, which I shared with expert lawyers at the time including Norfolk lawyer Richard Barr, who represented me in my 2006 claim against Flybe and who asked me to write a Statement of Truth, which I did.

The published conference paper is still available along with a brief film of BALPA General Secretary Jim McCauslan summing up the findings of the conference that the cause of ill health affecting both aircrew and

Statement of John Hoyte (JGH/H2738/002) 8

passengers had been identified and existed in 2005.

20. On 18th June 2007 I founded the Aerotoxic Association

Ltd at the UK Houses of Parliament to support other

victims of Aerotoxic Syndrome.

Web site www.aerotoxic.org continues only to publish

evidence from the 1950’s onwards of human poisoning

by oil fumes in confined spaces, which is in the public

interest and is currently managed by my colleague Ms

Bea Beaumont in Switzerland.

21. In 2006 I was fortunate to meet and be advised by private

Dr Sarah Myhill in Wales who helped me recover to

recover my health – she wrote a compelling paper for the

Aerotoxic Association in November 2007 clearly

detailing the cause of illness in both aircrew and



22. In 2007, I and many other professional aircrew and passengers shared our evidence to the UK House of Lords Science and Technology committee investigating ill health from contaminated cabin air, which was published.

Statement of John Hoyte (JGH/H2738/002) 9

23. In 2007 a documentary film ‘Welcome aboard Toxic

Airlines’ was produced as evidence by Fact not Fiction

Films of which I am a Director and included reference to

the Aerotoxic Association.

24. Dr Sarah Mackenzie Ross of University College London

did much research into toxic cabin air and published

several papers on the issue from 2006 – 2008 which

included evidence that 196,000 UK passengers a year

could be presenting symptoms of acute toxicity to GP’s

but has stated publicly that further research was stopped

by the UK CAA and British government in 2007 as being

somehow – unethical.

Dr Mackenzie Ross also gave evidence to the House of

Lords in 2007 and continues to work on this issue.


25. On 21st April 2008 BBC Panorama broadcast ‘Something in the air’ which featured Samantha Sabatino and her family and many other passengers from flight XLA 120 who had all been affected by fumes on 1st February 2007.

Samantha Sabatino also gave her evidence to the House of Lords in 2007.

Statement of John Hoyte (JGH/H2738/002) 10

Royal Society for the Prevention of Accidents (ROSPA)

and many other media outlets covered the details of



26. Much government ‘research’ has been done over the past 12 years but not once have the concentrations of identified toxic chemicals in a visible oil fume event been published for politicians, doctors, lawyers and scientists – which denies them critical evidence of a cause of public ill health.

Cranfield University, which is funded by the airline manufacturers, have been particularly criticised for never publishing the concentrations of highly toxic chemicals identified in a visible oil fume event, despite being told how to generate such a visible oil fume event on the ground in a BAe 146 for ease of testing in November 2007. They, the CAA and aircraft and engine manufacturers continue to claim that a ‘Fume event’ is difficult to measure…

‘Further research’ is being done and that is the mantra of governments who must be seen by the public to be doing something – yet always playing for time and never

Statement of John Hoyte (JGH/H2738/002) 11

(understandably) admitting any liability for known harm

caused to both aircrew and passengers.

27. As a result of running the Aerotoxic Association for over

11 years I have received and sent many mails (250,000)

and received testimonies from many other members of

the public from all over the world who have been affected

by oil fumes whilst flying, but their testimonies have

never been asked for, accepted or believed as being true

by researchers – even following an oil fume event which

has been logged formally as an ‘Accident’ where the

victims (including child passengers and infants) have

been taken to hospital for emergency treatment.

28. On 3rd September 2010 Turner v’s East West Airlines

legal case was won in a High Court of Australia after 18

years of public Court process and many Appeals

following a fume event incident in a BAe 146 in 1992.

Turner had also given her evidence to the House of Lords

in 2007.


29. In 2011, I was being assisted by the Brain Injury Rehabilitation Trust (BIRT) and was tested by the NHS at Leamington Spa hospital by Psychologist Mr

Statement of John Hoyte (JGH/H2738/002) 12

Poppleton (which was witnessed by Mark Smith of

BIRT) and was scored at ½ / 10 or in the ‘impaired’

range. I asked Mr Poppleton whether this result was

caused by airline flying? and he replied in words to the

effect: ‘That would be inconvenient for the air industry’.

30. Richard Mark Westgate contacted the Aerotoxic

Association on 16th March 2012 by e mail and he went to

The Netherlands for specialist treatment but died on

12.12.12 – his chronic ill health before contacting me was

completely covered-up by a ‘new’ Coroner at the

eventual inquest into his death on 13th April 2017.


31. Many aircrew and passengers have had body samples tested over the past years by skilled international scientists and laboratories to prove exposure to toxic air, yet it would appear that governments are suppressing such testing as for example, fat is still not tested by the UK NHS, yet that is where the toxins are stored.

Human hair samples are presently being tested in France and organophosphates are found in the hair samples of aircrew, yet not in their partners samples – confirming an

Statement of John Hoyte (JGH/H2738/002) 13

occupational exposure.

It is also known that post mortems, including that of

Richard Westgate, showed evidence of metals in the

aircrew brains which could only have come from jet

engines absolutely proving the route of exposure.

Further post mortems will only confirm the existing

strong available evidence.


32. Professor Michael Bagshaw (a former BA doctor) was interviewed by Australian 60 minutes ‘Toxic Flyer’ in 2013, but has never been interviewed by the media since, almost as if he is somehow beyond justice or open to public examination.

The Australian presenter, Tara Brown, introduced the Aerotoxic issue as being the ‘Asbestos of the airline industry’ and interviewed Professor Bagshaw which still summarises the present position of the Aerotoxic issue for many people.

Passenger Samantha Sabatino also appeared in this documentary.

Statement of John Hoyte (JGH/H2738/002) 14

Yet Professor Bagshaw persists in defending industry and

recently even publicly criticised the publication of a

recent World Health Organisation paper on the Aerotoxic

issue in a letter to the Royal Aeronautical Society (RAeS)

but was also in turn criticised in a later RAeS magazine

letters by one of the authors, Dr Susan Michaelis, who

was also a former BAe 146 pilot and is an expert in such

Aerotoxic matters.

It must be stated that 100% proof is never need in law for

matters of human health.

33. In 2015 a German Wings flight crashed in the French

Alps with the co pilot Andreas Lubitz accused of

committing suicide and yet evidence exists that he was

unconscious when the Airbus crashed, and that

contaminated cabin air was a part cause – another

industry cover up.


34. In July 2015 a German documentary film ‘Unfiltered breathed in air – the truth about Aerotoxic Syndrome’ was produced and shown by journalist Tim Van Beveren in Berlin, Germany.

Statement of John Hoyte (JGH/H2738/002) 15

German crews demonstrated against regular toxic air

exposures at Berlin and Frankfurt airports and I spoke

publicly at both demonstrations.

35. There have been many other legal cases worldwide over

the past years, but all of them are ‘Settled out of Court’

and paid off – thus preventing the Aerotoxic public health

cover up from being known to politicians and the public.

The Sabatino v’s Boeing passenger case of 2007 was

never settled but was claimed to be a ‘Great Victory for

the passengers’ by Stewarts Law in 2010.


36. Recently, ‘Dirty sock’ odours have been confirmed and accepted as OIL in jet airliner cabins by American Airlines checklists, which crew consult to identify odors.

‘Dirty sock odors’ should be a memory item for all jet pilots.

Yet Hazmat crews and the US media persist in reporting ‘Dirty sock odors’ as ‘mysterious and unidentified’ whilst crews and passengers are taken to hospital as sick patients.

Statement of John Hoyte (JGH/H2738/002) 16

An FAA funded Medical Health Protocol for Health

Professionals was widely published in 2009 in which

‘Dirty sock odor’ was specifically mentioned.

If anyone Googles ‘Dirty sock odor’ they would find out

a simple answer:


37. It is more than embarrassing for professional aircrew who

have been affected to be told by the so-called

‘independent’ Committee on Toxicity (COT) and some

doctors that sufferers of gassing and poisoning by toxic

chemicals in the confined space are experiencing a

‘Nocebo effect’ or that it’s ‘All in the head’ and not

caused by a 60 year old known design flaw found in most

commercial jet aircraft.

How could 60 random members of the public, on a single

flight, all experience a Nocebo effect?


38. There have been repeated international calls for toxic air detectors and carbon monoxide detectors to provide evidence of the chemicals found in bleed air jet airliners – most recently US Senator Blumenthal and other senators

Statement of John Hoyte (JGH/H2738/002) 17

introduced a Bill on 25th July 2017 ‘To Protect Airline

Passengers and Crew from Toxic Cabin Air’.

Yet as only ‘noses’ of aircrew are used to report the

fumes – the evidence can easily be misrepresented and

suppressed by the authorities and airlines.

Whilst light aircraft are normally fitted with Carbon

Monoxide detectors.

There is even evidence of Carbon Monoxide detectors

being used in front line RAF fighter in WW2.

39. In around 2016, it was understood that several pilots –

including Eric Bailet (French pilot), Janet Bevan (British

pilot) and others from low cost airline Easyjet were

experiencing mysterious ill health at the same base in

France and went to a criminal Court in Paris with their



40. In the summer of 2017 Easyjet changed the engine oil to Nyco oil, which is a safer oil formulation which has been known about since 2007.

In September 2017 Easyjet publicly announced that they would be fitting bleed air filters and detection systems at

Statement of John Hoyte (JGH/H2738/002) 18


an International Cabin Air Conference in London. However there was no admission that the changes were due to sick aircrew and customers or the criminal Court case.

The Easyjet criminal legal case was well reported on Zembla Dutch TV in two programmes in November 2017 (Zembla have also reported twice previously on the Aerotoxic issue) but Aerotoxic appears to be banned by the UK media with no free debate on the BBC for example. Aerotoxic is allowed to be reported on ITV news when it suits the independent broadcaster, but only when a new ‘story’ appears to entertain their viewers.

But no public debate of the common cause of illness or the available and known solutions which are available now – is possible.

At the September 2017 London conference Michael Rawlinson QC, a legal expert in Aerotoxicity claims, and who legally represented the Westgate family publicly stated that the Aerotoxic issue was at its ‘tipping point…’.

Statement of John Hoyte (JGH/H2738/002) 19

41. In late July 2018 it was reported by one of the French

EasyJet pilots that the illness Aerotoxic Syndrome was

about to be formally recognised and accepted in France

by the end of August 2018.

It is also known that the Easyjet criminal case would be

concluded in the autumn or by the end of 2018.


42. Politicians have consistently failed to believe professional aircrew and passengers sworn and unsworn Testimonies, leaving these people wondering exactly how to communicate evidence of their illnesses to the authorities.

After my date of knowledge of the cause of public ill health in 2006, I was well represented by John Maples MP who took an active interest in the issue until 2010, when he left office.

Jeremy Wright MP represented me from 2010-2013 but failed to take any interest.

I was also represented by Simon Wright MP and most recently by Clive Lewis MP – both of whom failed and still fail to take the public health issue seriously or even

Statement of John Hoyte (JGH/H2738/002) 20

answer formal correspondence.

Clive Lewis MP has a copy of my Aerotoxic book,

written in 2014.

However, Norwich North MP Chloe Smith did at least

acknowledge the Aerotoxic issue through a friend and

confidant Ian Warren – recently.

Lord Paul Tyler was aware of the issue in the 1990’s and

at the BALPA conference of 2005 as is The Countess of

Mar, who is our present champion in the UK House of



43. Captain Julian Soddy of Norfolk is the pilot who probably knows more about the Aerotoxic issue than most pilots as he was a BAe 146 pilot who was grounded by his Norfolk GP due to toxic air in 2000.

He went on to chair the BALPA Contaminated Air Quality conference of 2005 and was in BBC Panorama documentary in 2008 and Chaired the BALPA retired Flight Crew committee. He also gave his evidence to the House of Lords in 2007. He has also been in numerous

Statement of John Hoyte (JGH/H2738/002) 21

other toxic air documentaries since 2005.

Another Norfolk BAe 146 pilot who also appeared in

‘Welcome aboard Toxic Airlines’ was Capt. Ray Godfrey

who subsequently died and suffered from so-called


44. Apart from my flying log books which are legal

documents, I kept a detailed personal diary from 17th

October 2006 – 23rd July 2013 and from 1st January 2018

to 1st June 2018.


45. In 2013 I financially backed a fictional film about the Aerotoxic issue – ‘A Dark Reflection’ (Later renamed ‘Flight 313: The Conspiracy)

I published through Pilot Press Ltd, which I founded in 2014. ‘Aerotoxic Syndrome – Aviation’s Darkest Secret’ which was ‘Peer reviewed’ and initially Ghost written by Philip Whiteley and edited by Susan Curran. The Foreword was by specialist aviation journalist David Learmount who wrote for Flight International and is an expert in the history of Aerotoxic Syndrome since around 2006.

Statement of John Hoyte (JGH/H2738/002) 22

In 2017 ‘A Tale of Two Ag Pilots’ was published with co

director Captain Peter Lawton, who is now my

‘Spokesman’ as he taught me to fly in 1977, he is a

Toastmaster and a professional colleague.


46. Since November 2014 I have been involved with flight simulation and founded Simulator Flying Ltd. (Sim-Fly Norfolk) in 2015 and continue to work from Old Buckenham airfield, Norfolk offering the public experiences in the safety of flight simulators.

The main reasons for doing this work is to continue to ‘fly’, to demonstrate that professional pilots who have been previously injured can recover their health and get back to normal work and finally, every Sim-Fly customer receives a brief introduction to Aerotoxic Syndrome public health issue as a public service using the Sabatino flight of 2007 as an example of positive evidence of ‘Aerotoxic poisoning’.

Many members of the public, media, friends and family know about the Aerotoxic issue and understandably few have the public duty to deal with it and frequently describe the issue as an ‘Obsession’ – knowing the cause

Statement of John Hoyte (JGH/H2738/002) 23

of mass public ill health?


47. I have been concerned to learn over the last 12 years of many aircrew colleagues from the past 40 years who have contracted so-called ‘mysterious’ neurological diseases including Parkinson’s, Alzheimer’s, MND and MS – but the NHS choose not yet to recognise ‘so-called’ Aerotoxic Syndrome.

It is also known that retired aircrew know of the existence of the cause of ill health due to BALPA activity over the years, but as Aerotoxicity only affects around 30% of the population, it continues to be covered up by the majority and little known.

Clearly the risk to future aircrew is significant where large numbers of passengers can be affected on a single flight and where pregnant women, children and infants are particularly vulnerable.

Modern science has made it possible for those who are vulnerable to Aerotoxic Syndrome to be identified in advance by their DNA for around the past 5 years and many other diagnostic tests exist but have been

Statement of John Hoyte (JGH/H2738/002) 24

comprehensively and systematically dismissed by the

medical establishment but many of them were covered at

the BALPA 2005 conference.

48. In July 2017, journalist Mr Ian White of Front Page

Media interviewed passenger Samantha Sabatino

extensively by telephone and wrote an updated and

detailed testimony since the passenger Court case in the

US was suddenly and unexpectedly dropped by Stewart’s

Law in early 2012.

In November 2017, Ms Nicola Barrell (a former Archant

journalist) physically met Samantha Sabatino and

interviewed her about her experience since 2007, which

has continued to affect their whole family badly.

Ms Barrell then accompanied me to an open public

meeting in Belgium where she met Dr Michel Mulder

and many other Belgian aircrew who are suffering with

Aerotoxic Syndrome.


49. In 2017, a report by the World Health Organisation (WHO) ‘Aerotoxic Syndrome – a new occupational disease?’ was published.

Statement of John Hoyte (JGH/H2738/002) 25


In 2018 a paper was published by the British Medical  Journal. ‘Aerotoxic syndrome: a new occupational  disease?’ (adverse health effects experienced by aircrew  exposed to aircraft contaminated air).

It is not known why researchers do not understand that  contaminated air does not only affect aircrew, but  passengers also.

It would appear that it doesn’t matter what new Aerotoxic  research is published – the power and wealth of the airline  industry can prevent the mass public from learning about  an inconvenient cause of mass public ill health.

A presentation on Aerotoxic Syndrome will be made by  Professor Vyvyan Howard to an international aviation  medical conference in September 2018.

The Global Cabin Air Quality Executive (GCAQE) on  25th and 26th September 2018 are also holding a regular  annual meeting. I attended the first GCAQE meeting in

September 2006, so I have been reluctantly and publicly  linked to this issue for around 12 years but experienced  the first serious ill health over 28 years ago.

Statement of John Hoyte (JGH/H2738/002) 26


50. As a result of wishing to advise the public of the hidden dangers of flying I contacted Archant media in Norwich who first published ‘stories’ about Aerotoxic in 2014 and they have since reluctantly written about the issue for the public interest and have continued to publish occasional articles and my letters.

The Guardian newspaper Editor was sent updated evidence of the Sabatino case in July 2018 but has failed to acknowledge receipt of the new evidence.

I was awarded a prize by satirical magazine Private Eye for the web site www.aerotoxic.org in 2010, but since then along with the entire UK media have failed to update the public on significant Aerotoxic developments – particularly that a British airline is in a French criminal Court, and this will be difficult for them to explain later to the public in 2018 and a part of the reason for making this legal Statement.

It is challenging to live and work amongst others who know the Aerotoxic issue exists, but do not share the objectives of those who have been affected, as they appear to put the health and well being of the airline

Statement of John Hoyte (JGH/H2738/002) 27

industry ahead of human health – whilst claiming the

opposite in public.


51. I was contacted in around 2011 by John Lind of the US who is a former aviation insurance expert and USAAF pilot but whose daughter works for an American airline and had got sick from repeated oil fume exposures.

John Lind has sent many offers of assistance and advice to American airlines offering help to resolve the toxic air issue, which I and others have been privileged to be included with this shared evidence.

I have shared this evidence with others including local lawyer Ben Dures and former MP Dr Ian Gibson, who is a co-director of the Aerotoxic Association.

In early 2018 I was very concerned to informed by John Lind that the FBI had begun a formal investigation into the Aerotoxic issue as fraud had been identified by the insurance industry and that I could be investigated – always confident that we have done our best to expose the fraud since 2006.

John Lind explained in writing, for example that – US

Statement of John Hoyte (JGH/H2738/002) 28

industry doctors are claiming in public Courts that ‘It is

safe to drink jet engine oil, so breathing the fumes cannot

cause ill health’. Which is clearly wrong and criminal.

I visited Norfolk Police at Wymondham on 4th April 2018

to advise them of the US fraud and shared John Lind’s

evidence letter – so as to put it on the public record, but

got no acknowledgement apart from a dated receipt.

I had previously been interviewed by a Detective

Inspector from Norfolk Police in connection with the

Aerotoxic criminal activity during the summer of 2015,

this was partly confirmed by a former Norfolk Police

officer in early 2018 although ‘not answering

correspondence’ seems to be a recurring effective tactic

of the authorities over the past 12 years.


52. 21st April 2018 was the thirteenth anniversary of the 2005 BALPA London conference and the tenth anniversary of the 2008 BBC Panorama documentary.

A professionally composed Media release was drawn up by PR expert Chis Brown drawing the media’s attention to this historical evidence along with the 17th March 2016

Statement of John Hoyte (JGH/H2738/002) 29


Westminster debate where individual calls for an open public inquiry into Aerotoxic Syndrome were made by several MP’s in the House of Commons debate.

But despite the media release being sent to national media outlets, including the BBC, well before the anniversary of 21st April 2018 – it was completely ignored. This confirmed the ongoing UK media blackout on any Aerotoxic evidence being published and even Parliamentary appeals for a public inquiry into a known cause of public ill health being ignored by the media.

I travelled to The Netherlands on 22nd April 2018 as Aerotoxic matters are allowed to be shared with the public outside of the UK and met with a Dutch journalist Paul Eldering of De Telegraaf and gave him the same evidence, which he still has in his possession. I also wished to visit other Dutch flight simulator companies to check on how they presented their businesses to the public, but the Dutch tend to only train pilots, not entertain the public. I also visited my friend and colleague Dr Michel Mulder and others to understand medical research progress.

Statement of John Hoyte (JGH/H2738/002) 30

53. Due to the repeated mention of ‘criminal’ and ‘cover up’

in the public domain, it was decided in April 2018 to send

Testimonies to the International Criminal Court at The

Hague in The Netherlands for an eventual public inquiry

after the closing date of 31st August 2018.

This Statement of Truth will be amongst the many other

Statements which have been received to date from

aircrew around the world and we all have a public duty

and are free to speak.


54. I have no financial compensation interest in this health matter now, as it concerns public health which is paramount and is in the public interest.

But I do want the public to be represented, diagnosed and treated correctly and the known technical solutions introduced urgently in the future.

Statement of Truth

1. I believe that the facts stated in this witness statement are true.

Signed:: ………………………….

Full name of Client


Statement of John Hoyte (JGH/H2738/002) 31

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