Toxic Cabin Air/Aerotoxic Syndrome

[Flipster130]

Not all smoke and fumes incidents are 'fume events' caused by oil from the bearing seals - could just be an electrical short or a burning pie.......

[tdracer]

Originally Posted by Flipster130

Not all smoke and fumes incidents are 'fume events' caused by oil from the bearing seals - could just be an electrical short or a burning pie.......

This is very much the case - back when I had access to the database, I would routinely scan the events - mainly for items that were relevant to my area (once discovered a very scary relevant event that the operator had not bothered to report to Boeing or the engine company, but had submitted to the feds). But also out of general interest/curiosity.
"Fume" events were fairly common, but the vast majority were either electrical or galley related - those attributed to engine bleed air were uncommon (and often maintenance related - such as improperly performed engine washes).

When Boeing was developing what became the 787, it was touted as an efficiency enhancement (engine cycle better optimized by eliminating service bleeds - something that really didn't bear fruit) - not improved cabin air quality. It's probably worth noting that - since the 787 was launched, Boeing has also launched new models of all its other passenger aircraft (including new engines) - 737 Max, 747-8, and 777X (the hasn't been offered as passenger aircraft for some time). This would have been a golden opportunity to incorporate 787 air cycle systems for cabin pressurization - which would have allowed them to claim an improved cabin environment as a competitive advantage over Airbus. Yet all the new models use the same basic engine bleed air system that dates back to the 707. Obviously Boeing does not think it's a major issue.

[Flipster130]

Originally Posted by tdracer

......Yet all the new models use the same basic engine bleed air system that dates back to the 707. Obviously Boeing does not think it's a major issue.

I might be wrong but I suspect that retro-fitting 787 type air cycle pressurisation/air cond systems to some older frames night be prohibitively costly, even if the flight experience of such systems is vastly better for both pax and crew.

Also, if I were being cynical, then perhaps manufacturers, airlines and regulators do not want to admit more-openly that the past 70 plus years of experimenting with engine bleed air for pressurisation and air conditioning has been an abject failure. The spectre of a class action by all those injured, maimed and killed as result of the experiment would be scary - it might be the end of many businesses and jobs. Whilst that IS a serous consideration, it doesn't make it right - morally or legally - to deny the past and not learn from one's mistakes.

[Manual Pitch Trim]

Another A319 burning odour event

Aviation Herald


A United Airbus A319-100, registration N809UA performing flight UA-531 from Chicago O'Hare,IL to Tucson,AZ (USA) with 51 people on board, was enroute at FL380 about 110nm west of Wichita,KS (USA) when the crew decided to divert to Wichita due to a burning odour on board. The aircraft landed safely on Wichita's runway 19R about 25 minutes after leaving FL380.

A replacement A319-100 registration N891UA reached Tucson with a delay of about 4.5 hours.

[Manual Pitch Trim]

ATR contaminated air

Incident: Azul AT72 at Curitiba on Dec 11th 2023, burning odour on board


An Azul Linhas Aereas Avions de Transport Regional ATR-72-212A, registration PR-AKJ performing flight AD-5096 from Curitiba,PR to Cascavel,PR (Brazil), was accelerating for takeoff from Curitiba's runway 15 when a burning smell became detectable on board of the aircraft. The aircraft stopped the climb at 7000 feet and returned to Curitiba for a safe landing on runway 15 about 17 minutes after departure.

Brazil's CENIPA reported during the takeoff phase a burning odour was noticed, the crew decided to return to the airport of origin for an uneventful landing.

[Manual Pitch Trim]

Spirit Airlines FAs to hospital fume event

https://www.aerotime.aero/articles/s...8%2C+2023Three Spirit Airlines flight attendants were taken to hospital after they were exposed to fumes while carrying out preflight checks on an aircraft.

New Jersey State Police confirmed that troopers were sent to Atlantic City International Airport (ACY) on December 17, 2023, after the crew members were exposed to fumes around 5:45 am local time.

The Spirit Airlines flight attendants were subsequently taken to a nearby hospital for medical evaluation by doctors.
The news website NJ.com, said Jeffrey Lebron, a detective and police spokesperson, confirmed details of the incident later in the day.

[Sailplaneflier]

Originally Posted by Flipster130

Not all smoke and fumes incidents are 'fume events' caused by oil from the bearing seals - could just be an electrical short or a burning pie.......

What would help might be CO2 / combustion product detectors in cabins as I've personally experienced several events where engine bleed air smelled like jet fuel / burning oil. It seems it's almost 20% of the time.

[tdracer]

Originally Posted by Sailplaneflier

What would help might be CO2 / combustion product detectors in cabins as I've personally experienced several events where engine bleed air smelled like jet fuel / burning oil. It seems it's almost 20% of the time.

Remember - if this is on the ground, it could very well be exhaust from nearby jet engines getting sucked in by the aircraft engine(s). I noticed this just a couple days ago while sitting in a 777-300ER in Jakarta. Not long after engine start, but before commencing taxi, I noticed the distinct odor of Jet A exhaust in the aircraft air. The external air quality at many airports is far from good...

[Sailplaneflier]

That, Sir, is a very likely reason why. Yes, it was Jet A and lots of aircraft at DEN.

[Flipster130]

Not so much CO2 detectors perhaps but CO detectors....we have these in our piston tin cans and houses - so why not in airliners?
CO is as likely, possibly even more so than Organo-Phosphates, to be the cause of fume events and the physical and neurological effects that ensue.
Also, there are much more modern and effective CO detectors than those bits of card with palladium sulphate that change colour. Modern detectors (alarms 100-400ppm) could be easily retrofitted to most modern airliners. Yes some issues with picking up fumes from nearby ac on ground - but once airborne, should not go off (WOW interlink?)
However, there are plenty other nasties created when aero-engine oil is pyrolised......not sure there is much research on this. However, the insidious effects of CO are well known
Footballer Emiliano Sala Crash Channel Islands

[Manual Pitch Trim]

My understanding is that over 150 VOC volatile organic compounds have been found on aircraft CO is just one

plese see this EASA report

https://www.easa.europa.eu/en/downloads/22219/en



Here is the peer reviewed report on the highly recommended Van Netten air sampler

http://www.bleedfree.eu/wp-content/u...craft-2008.pdf



This is the best way to take multiple samples in different aircraft.
Van Nettens lab will analyze the filters for TCP isomers, i.e. the tell tale, and toxic, chemicals that indicate bleed air contamination from jet engine oils. The filters we use do not measure UFPs as such.

This is for a good reason as UFP are generated from all kinds of different sources, anything from laser printers to diesel engines, e-cigarettes and wild fires.
The filters thry use will identify specific toxins in the air that we breathe and trace these toxins to their source within the aircraft. A particular reading of UFP in an aircraft does not tell you their toxicity or their source.


After exposure, you can take out the filter and replace it with a new one, replace the batteries and get the sampler ready for another measurement on another flight.
The exposed filter can be placed in an appropriate container, i.e. a small zip lock baggy and sent to me in a standard letter which , after receipt, can be given to our lab for analysis.

The specific details etc. come with the VN air sampler after purchase.

Regarding prices for a VN air sampler, these are currently for sale at $250 USD each.
An analysis for TCP isomers using GC/Mass spec. for TCP isomers will cost $150 USD/filter.


Chris van Netten, MSc, PhD
Professor Emeritus, Environment Toxicology
School of Population and Public Health
Faculty of Medicine, UBC


Tel. H 604-462-9476

[island_airphoto]

Originally Posted by Flipster130

Not so much CO2 detectors perhaps but CO detectors....we have these in our piston tin cans and houses - so why not in airliners?
CO is as likely, possibly even more so than Organo-Phosphates, to be the cause of fume events and the physical and neurological effects that ensue.
Also, there are much more modern and effective CO detectors than those bits of card with palladium sulphate that change colour. Modern detectors (alarms 100-400ppm) could be easily retrofitted to most modern airliners. Yes some issues with picking up fumes from nearby ac on ground - but once airborne, should not go off (WOW interlink?)
However, there are plenty other nasties created when aero-engine oil is pyrolised......not sure there is much research on this. However, the insidious effects of CO are well known
Footballer Emiliano Sala Crash Channel Islands

I have a CO detector for flying. It is very useful for airplanes that use air passed over the exhaust manifold for cabin heat. All the pressurized jet aircraft I know of take bleed air from ahead of the part of the engine where the fuel is introduced, so it should not have any way to have combustion products in it. The issue here is more a fine mist of oil leaking from bad seals at the front of the engine, which would not show up on a CO meter AFAIK.

[Flipster130]

Evidence shows CO will bereleased when oil is pyrolised......wonder if we should not all carry CO monitors when flying, esp if manufacturers don't/won't fit them

[island_airphoto]

Originally Posted by Flipster130

Evidence shows CO will bereleased when oil is pyrolised......wonder if we should not all carry CO monitors when flying, esp if manufacturers don't/won't fit them

I have had one in my flight bag ever since a CO leak nearly killed me, but I did not know they would pick up on oil.

[Flipster130]

Its not the oil per se its still the insidious CO
C

[TLoraine]

Contaminated air update

I have been researching this issue for over 20 years. In September this year, in London, a major update will be given by OEMs, scientists, doctors and others on the issue.
Key points:

1. A new blood test funded by unions representing pilots, flight attendants, engineers and off shore oil works globally and the Royal Australian Air Force will be presented by the researchers. The blood test can confirm if an exposure to the aryl phosphates in the oils (anti wear additives) has taken place. It will also be published in a peer reviewed journal soon.
2. New engine oils which a related patent by the manufacturer states will help address the issue of Aerotoxic Syndrome will also be discussed.
3. The debate on whether flight deck monitoring, as recommended twice by the UK AAIB, is a positive or negative step on flight safety will also be discussed.
4. New bleed air filtration / air cleaning technologies will be presented by OEMs.
5. Recent FAA research in bleed air contamination detection.
6. Etc......

A list of confirmed presentations and more information is available at: https://www.aircraftcabinair.com/speakers

[island_airphoto]

Originally Posted by Flipster130

Its not the oil per se its still the insidious CO
C

Thread diversion - I have long wanted someone to do a study of low levels of CO on pilots. If a person at sea level is running at 6,000 feet brain-density-altitude, they won't notice. If you are flying at 8,000 feet AGL or with 8,000 feet cabin pressure, that will degrade your performance quite a bit. 14,000 feet brain altitude is not good. It would explain some mystery crashes where what seemed like good pilots in good airplanes just somehow forgot what they should have been doing.

[netstruggler]

Originally Posted by island_airphoto

Thread diversion - I have long wanted someone to do a study of low levels of CO on pilots. If a person at sea level is running at 6,000 feet brain-density-altitude, they won't notice. If you are flying at 8,000 feet AGL or with 8,000 feet cabin pressure, that will degrade your performance quite a bit. 14,000 feet brain altitude is not good. It would explain some mystery crashes where what seemed like good pilots in good airplanes just somehow forgot what they should have been doing.

I haven't heard of low levels of CO being a problem. Do you mean lower levels of CO than normal or a low level CO increase?

I think the effects of increased levels of CO are pretty well understood. They're bad.

Edit: It's just occurred to me that you might mean Cabin Oxygen rather than Carbon Monoxide? If so ignore the above.

[Airclues]

Progressive Supranuclear Palsy

[Fortissimo]

Originally Posted by island_airphoto

Thread diversion - I have long wanted someone to do a study of low levels of CO on pilots. If a person at sea level is running at 6,000 feet brain-density-altitude, they won't notice. If you are flying at 8,000 feet AGL or with 8,000 feet cabin pressure, that will degrade your performance quite a bit. 14,000 feet brain altitude is not good. It would explain some mystery crashes where what seemed like good pilots in good airplanes just somehow forgot what they should have been doing.

Not sure where you get the 8000ft performance degradation from. The RAF allowed ops without additional oxygen up to 10K ft, regulators were tuned to provide increasing concentration until 18K ft, then 100% required to 33K ft. Above that, you need it delivered under pressure.