Apparently it seems to be that only a low percentage of cabin fumes events finally get registered by the authorities, at least reading these avherald articles:

https://www.avherald.com/h?article=4b6eb830/0006&opt=0

https://www.avherald.com/h?article=4c140b24&opt=0

Is this what is happening? If actually an underreporting exists, is this delaying the implementation of measures to mitigate the heath risk associated to both chronic and acute exposition for passengers and crew?

It's just not a problem.

abies111 wrote:

Apparently it seems to be that only a low percentage of cabin fumes events finally get registered by the authorities, at least reading these avherald articles:

https://www.avherald.com/h?article=4b6eb830/0006&opt=0

https://www.avherald.com/h?article=4c140b24&opt=0

Is this what is happening? If actually an underreporting exists, is this delaying the implementation of measures to mitigate the heath risk associated to both chronic and acute exposition for passengers and crew?

It's a huge problem. A guy I know at another airline is in the hospital from it. It's a problem that was known in the military since the 1950's/1960s. Look up "aerotoxic syndrome". Keep in mind that you will not usually be able to access any data on fume incidents since airlines can hide things through SMS/ASAP. Also, 99.99% of airlines are out of their element on this problem. Many of the volatile organic compounds aircraft occupants are exposed to have no odour whatsoever. You simply have no idea that you're being exposed to it without expensive equipment or immediate blood testing using a very specific protocol that only research scientists use. You can drop dead 10 years later from a toxic exposure and without any other symptoms. Remember how hard it was to get the tobacco industry to admit that smoking kills. The problem is that in the USA, there is a general apathy about things that hurt you. For example, the fire retardants used on furniture and carpets is toxic to humans and causes cancer. There are so many toxins around you and so many causes of cancer (amongst other illnesses), that most people just stop caring.

Yeah. It's a big conspiracy.

You're not from California, by chance, are you?

747Whale wrote:

Yeah. It's a big conspiracy.

You're not from California, by chance, are you?

Yet some of the big conspiracy guys are putting a little more effort than that in explaining their views:

https://www.fzt.haw-hamburg.de/pers/Sch ... binAir.pdf

Surely a waste of time, as there is nothing to improve in any aircraft system, by definition, if related to health and confort issues, isn't It?

747Whale wrote:

Yeah. It's a big conspiracy.

You're not from California, by chance, are you?

Ding ding ding! Winner lol.

Perhaps Boeing and Airbus should develop some giant multi-stage HEPA filters for their bleed air / packs. I'm sure every airline would drop 10s of thousands of bucks for the option, which gets them zero $$ in return.

Actually no, they wouldn't.

Plus these smoke issues aren't due to inlet air filtration problems, they're due to seal failures inside the engines. Once such a failure occurs, you will NEVER be able to filter out that type of smoke from the cabin - it's simply not possible.

Maybe you could create a system to identify which bleed air source is generating the cabin smoke (APU, engine 1-4, etc) and isolate it from the cabin air circuit, but I'm not sure if that would be adequate for pressurization at higher altitudes - granted if an engine failed you'd need to descend anyways. Either way it's an expensive system which would need to be created for all aircraft, not just this one engine on this one model.

greendot wrote:

It's a huge problem. A guy I know at another airline is in the hospital from it. It's a problem that was known in the military since the 1950's/1960s. Look up "aerotoxic syndrome". Keep in mind that you will not usually be able to access any data on fume incidents since airlines can hide things through SMS/ASAP. Also, 99.99% of airlines are out of their element on this problem. Many of the volatile organic compounds aircraft occupants are exposed to have no odour whatsoever. You simply have no idea that you're being exposed to it without expensive equipment or immediate blood testing using a very specific protocol that only research scientists use. You can drop dead 10 years later from a toxic exposure and without any other symptoms. Remember how hard it was to get the tobacco industry to admit that smoking kills. The problem is that in the USA, there is a general apathy about things that hurt you. For example, the fire retardants used on furniture and carpets is toxic to humans and causes cancer. There are so many toxins around you and so many causes of cancer (amongst other illnesses), that most people just stop caring.

I agree 100% with this.

It is a silent killer. I would never ever be an airline pilot because it is one of the highest exposure occupations.

RJMAZ wrote:

I agree 100% with this.

It is a silent killer. I would never ever be an airline pilot because it is one of the highest exposure occupations.

You agree with it, based on what?

Highest exposure occupations to what?

I'm going on toward my fourth decade doing this....as a pilot.

I dont' think I've ever met another pilot (that is, someone who actually does this for a living, rather than reading about it on the internet somewhere) in all that time, that's ever expressed a concern about "toxic fumes" in the aircraft.

Now, over the years I've been soaked in herbicide while spraying, soaked in engine oil while servicing large radial engines, soaked in avgas and jet fuel, and have worked around a lot of MEK and other chemicals, as well as dispensed a lot of chemicals out of aircraft from economic poisons to fire retardant, and have flown widebody aircraft all over the globe and continue to do so...I have to say that flying an airline environment may be the safest and lowest-risk work I do, or have done. As far as toxic vapors in the bleed air, it really isn't an issue. It's just not.

I've been in large four engine aircraft when the interior was turned into a fog of red vapor after a failure of a hydraulic line. That's not particularly good, and in each case it was in special operations, not passenger flying, and in no case represented something one might expect from bleed air in the airplane.

There's a need for some people to classify every object in the world as cancer-causing and hazardous, the epicenter of this stupidity seems to hail from. California. I guarantee that after nearly four decades as both pilot and mechanic, if I thought there was any hazard to cabin air, I wouldn't be flying in that environment. There isn't.

I don't think I've ever heard a single pilot complain or express concern about this. Perhaps it's only those who have too much time to read conspiracy web sites that know about it; those of us who do it for a living wouldn't have a clue.

It's not a problem until it happens to you. In general, the number of incidents seem to be very low per number of flights. Statistically insignificant mathematically I would bet. But there have been multiple incidents where this occurs and people are certainly getting sick. Is it a long term cancer risk? That's unproven. I'm not afraid to fly because of this extremely low risk, but in my opinion it is worth a clean look in the design phase of new aircraft. From a design/engineering standpoint, why even risk cabin air getting mixed with contaminated air.

buzzard302 wrote:

It's not a problem until it happens to you.

Oh.

Thanks for sharing that.

747Whale wrote:

RJMAZ wrote:

I agree 100% with this.

It is a silent killer. I would never ever be an airline pilot because it is one of the highest exposure occupations.

You agree with it, based on what?

Highest exposure occupations to what?

I'm going on toward my fourth decade doing this....as a pilot.

I dont' think I've ever met another pilot (that is, someone who actually does this for a living, rather than reading about it on the internet somewhere) in all that time, that's ever expressed a concern about "toxic fumes" in the aircraft.

Now, over the years I've been soaked in herbicide while spraying, soaked in engine oil while servicing large radial engines, soaked in avgas and jet fuel, and have worked around a lot of MEK and other chemicals, as well as dispensed a lot of chemicals out of aircraft from economic poisons to fire retardant, and have flown widebody aircraft all over the globe and continue to do so...I have to say that flying an airline environment may be the safest and lowest-risk work I do, or have done. As far as toxic vapors in the bleed air, it really isn't an issue. It's just not.

I've been in large four engine aircraft when the interior was turned into a fog of red vapor after a failure of a hydraulic line. That's not particularly good, and in each case it was in special operations, not passenger flying, and in no case represented something one might expect from bleed air in the airplane.

There's a need for some people to classify every object in the world as cancer-causing and hazardous, the epicenter of this stupidity seems to hail from. California. I guarantee that after nearly four decades as both pilot and mechanic, if I thought there was any hazard to cabin air, I wouldn't be flying in that environment. There isn't.

I don't think I've ever heard a single pilot complain or express concern about this. Perhaps it's only those who have too much time to read conspiracy web sites that know about it; those of us who do it for a living wouldn't have a clue.

Anecdotal, unscientific, uninformed. Your arguments are no different than was used by mad hatters, radium painters, nuclear waste workers (now being compensated for by the VA), agent orange, asbestos, leaded paints, bisphenol-A, the tobacco industry, etc.....

I've also spent a lot of time bathed in 2,4-D, 2,4,5-T (agent orange), and a lot of other chemicals...agent orange is a wild hare and a crock, but that's another talk.

What's your scientific, informed evidence, then?

Another occurrence recently:

http://avherald.com/h?article=4c1b1b50&opt=0

The link provided by buzzard302 cites carbon monoxide. The article points to "fumes" which was not the case, but which evokes all kinds of images without saying a thing. Greendot above points to "aerotoxic syndrome," which is entirely different and no more scientific or verifiable.

While it's certainly possible on start up to ingest a little exhaust with a tailwind, or to get a bit of oil scent if the engines have been windmilling and there is trace oil in the lab seals, as soon as the engine is running oil leakage into the system is prevented. "aerotoxic syndrome" is more conspiracy theory than fact, with sites devoted to it (aerotoxic.org) presenting half-truth mixed with bad information...just the kind of thing that conspiracy nuts slather all over.

"Fumes" says nothing. The placebo effect is strong.

Seals are not "controlled leakage devices" as aerotoxic.org stipulates, and are not designed to leak. Moreover, lab seals aren't something that gradually wears out and leaks. The site refers to "both cabin and cockpit air" as if they're two different things. The site also points to organophosphates without any understanding of what that means, and tries to draw parallels between organophosphate poisoning and turbine oil and cabin air...which is ridiculous and smacks of ignorance. In discussing pressurized aircraft cabins, the same site refers the reader to a 1972 advisory circular, 20-32B, which has nothing at all to do with turbine aircraft or pressurization systems, but rather shrouds placed over exhaust on light single engine airplanes that burn avgas...problems which do not exist in any shape or form on pressurized aircraft, or turbine, or transport category aircraft. A true conspiracy site masquerading as legitimate science, it's clearly thrown together by those who know little or nothing about the subject, and which attempts to fiat psuedoscience into a believable pill that some are gullible enough to swallow. The site goes so far as to refer to circadian disruption ("jet lag") as "so called jet lag," and attempts to point to an "aerotoxic" atmosphere as the cause. Sorry kids, that ship sailed a long time ago, and "jet lag" as a function of circadian change is very well scientifically established.

Trying to sell a scare story as "fumes" might as well just be "bad air," and sounds much more legitimate when called "aerotoxic syndrome," albeit still a load of crap.

I think the op is getting confused by reports of smoke in the cabin which are mostly due to ACM failures or rarely a recirc fan burning out, nothing to do with the engines which get their bearing compartments vented overboard.

These types of incident always result in an aircraft turning back and are always reported.

https://youtu.be/cvdmK0toSCo

Well worth watching.

60 minutes even swab tested inside the planes cabin and found engine oil chemicals.

Well worth watching?? The first five minutes say otherwise. The ozzie pilot who is depicted in the captain seat wearing two stripes, the melodrama about passengers about to face certain death (the flight landed normally), the rabbiting on about being eight miles behind the airplane (ludicruous), destroyed all credibility before the flight got out of the gate.

The video purports that pilots are failing in the cockpit and becoming dangerous due to years of exposure to "aerotoxic syndrome," which is not true.

It's a sensationalist piece made not for professionals who know better, but for people not educated enough to know the difference.

Hack journalism at best.

"Contaminated air or fume events occur regularly on aircraft, no matter how old, or new they are." A lie. The video shows a cabin full of smoke. To call such events rare would be an understatement, but to show this while attempting to suggest labyrinth seal leakage into the cabin (pressurized seals which don't leak or wear, incidentally, and aren't "controlled leaks" as previously described) while depicting a cabin full of smoke, is laughable, non-sequitor, and straw-man.

The video doesn't name the flight, but talks of Helios 522, and attempts to infer that the crew was overcome by "fumes," resulting in a crash that killed all on board. This is a lie. The aircraft experienced a depressurization. In fact, just the opposite of "fumes." The claim is that "fumes" from pressurization are poisoning pilots and passengers, when this crash occurred for the opposite reason. A lie, but they paint it differently, don't they?

Conspiracy theorists. Yellow journalism. Panic mongering. Spreading the lie.

There will always be those who believe it, no matter how ridiculous it may be.

abies111 wrote:

https://www.avherald.com/h?article=4b6eb830/0006&opt=0

This article says it all.
Oil, hydraulic fluid or whatever are all pretty toxic. You wouldn't want them to be on your skin for too long, let alone vaporize and inhale.

RJMAZ wrote:

greendot wrote:

It's a huge problem. A guy I know at another airline is in the hospital from it. It's a problem that was known in the military since the 1950's/1960s. Look up "aerotoxic syndrome". Keep in mind that you will not usually be able to access any data on fume incidents since airlines can hide things through SMS/ASAP. Also, 99.99% of airlines are out of their element on this problem. Many of the volatile organic compounds aircraft occupants are exposed to have no odour whatsoever. You simply have no idea that you're being exposed to it without expensive equipment or immediate blood testing using a very specific protocol that only research scientists use. You can drop dead 10 years later from a toxic exposure and without any other symptoms. Remember how hard it was to get the tobacco industry to admit that smoking kills. The problem is that in the USA, there is a general apathy about things that hurt you. For example, the fire retardants used on furniture and carpets is toxic to humans and causes cancer. There are so many toxins around you and so many causes of cancer (amongst other illnesses), that most people just stop caring.

I agree 100% with this.

It is a silent killer. I would never ever be an airline pilot because it is one of the highest exposure occupations.

Do airline pilots have a higher mortality rate because of this? Please provide stats.

Long time (10+ years) lurker here. Compelled to reply here due to a recent experience.

I flew with Air Malta MLA to VIE. Upon boarding the old / mouldy sock smell was immediately noticeable. I asked the crew about this and they said that the captain explained to them that this wasn't a problem. Based on what I have read online, dispatching the plane in this situation does seem somewhat unusual. Would there be any way that the captain or maintainance was able to determine that the aircraft was fit to fly?

The smell did become less prominent in cruise but reappeared upon descent and when disembarking.

The fumes appear to have different effects on different people, also depending on where in the aircraft one is located. A person next to me mentioned they were feeling slightly nauseous. The old / mouldy socks smell does appear relatively common on aviation herald and nowhere have I seen what appears as a "fume event" being accepted as normal. Anyone have a different or similar experience?

Horstroad wrote:

abies111 wrote:

https://www.avherald.com/h?article=4b6eb830/0006&opt=0

This article says it all.
Oil, hydraulic fluid or whatever are all pretty toxic. You wouldn't want them to be on your skin for too long, let alone vaporize and inhale.

The article says it all, does it?

How do you suppose hydraulic fluid gets into the cabin atmosphere?

Tomesh wrote:

Long time (10+ years) lurker here. Compelled to reply here due to a recent experience.

I flew with Air Malta MLA to VIE. Upon boarding the old / mouldy sock smell was immediately noticeable. I asked the crew about this and they said that the captain explained to them that this wasn't a problem. Based on what I have read online, dispatching the plane in this situation does seem somewhat unusual. Would there be any way that the captain or maintainance was able to determine that the aircraft was fit to fly?

The smell did become less prominent in cruise but reappeared upon descent and when disembarking.

The fumes appear to have different effects on different people, also depending on where in the aircraft one is located. A person next to me mentioned they were feeling slightly nauseous. The old / mouldy socks smell does appear relatively common on aviation herald and nowhere have I seen what appears as a "fume event" being accepted as normal. Anyone have a different or similar experience?

Points to maintenance me thinks. The water separator coalescers socks (cloth filters) and/or Recirculation air filters need to be cleaned or replaced.

https://en.wikipedia.org/wiki/Environme ... rol_system
From Cold air unit topic in Wiki article.
The air is then sent through a water separator, where the air is forced to spiral along its length and centrifugal forces cause the moisture to be flung through a sieve and toward the outer walls where it is channeled toward a drain and sent overboard. Then, the air usually will pass through a water separator coalescer or the sock. The sock retains the dirt and oil from the engine bleed air to keep the cabin air cleaner. This water removal process prevents ice from forming and clogging the system, and keeps the cockpit and cabin from fogging on ground operation and low altitudes.

747Whale wrote:

Horstroad wrote:

abies111 wrote:

https://www.avherald.com/h?article=4b6eb830/0006&opt=0

This article says it all.
Oil, hydraulic fluid or whatever are all pretty toxic. You wouldn't want them to be on your skin for too long, let alone vaporize and inhale.

How do you suppose hydraulic fluid gets into the cabin atmosphere?

through the APU for example. I think you know the MD11 quite well. I have not heard of hydraulic fluid actually getting there, but it is possible. Once I spent 3 hours cleaning the APU inlet duct due to an oil smell event. There was actually engine oil standing on the lower edge inside the APU inlet. #2 engine and IDG remote fill ports are just behind the APU inlet in the tail cone. So are HYD components. there is this gutter around the inlet that should prevent any fluids running down the fuselage from entering the APU, but obviously this design isn't perfect.

The APU has no hydraulics attached. And yes, I do know the MD11 well.

In fact, on engines, which do drive hydraulic pumps, there is no way for hydraulic fluid to get into the engine and thus bleed air, either.

The MD11 is strictly a cargo aircraft. Are you aware of a single cargo crew claiming "aerotoxic syndrome?"

Other than the Cathay "crew member" in the video, the one sitting in the captain's seat while wearing two stripes...or the falsified report in the video inferring "fumes" brought down Helios 737...now we're inferring that hydraulic fluid magically migrates to the APU and enters the aircraft, or somehow gets into engine oil, which then works backward against labyrinth seals under pressurization, and is ingested to produce toxic "fumes" that destroy pilots and kill passengers?

This is a conspiracy theory, especially given that it's not remotely an issue to crew that fly the aircraft their entire lives...perhaps we're all keeping it a secret, in fear for our jobs? That kind of a conspiracy?

T54A wrote:

Do airline pilots have a higher mortality rate because of this? Please provide stats.

You could just do a google search and find dozens of research studies and hundreds of articles

https://m.medicalxpress.com/news/2018-0 ... ation.html

"Researchers at Harvard T. H. Chan School of Public Health, US found that out of the 5,366 flight attendants who participated in this study, slightly over 15% reported ever having been diagnosed with cancer. Accounting for age, the authors found a higher prevalence in flight crew of every cancer outcome examined in this study compared to the general population, including breast (3.4% of flight crew compared to 2.3% in the general population), uterine (0.15 % compared to 0.13%), cervical (1.0% compared to 0.70%), gastrointestinal (0.47% compared to 0.27%), and thyroid (0.67% compared to 0.56%) cancers.

This is striking given the low rates of overweight and smoking in this occupational group."

747Whale wrote:

The APU has no hydraulics attached. And yes, I do know the MD11 well.

Have you read what I wrote? I never said the APU has any Hydraulic components attached.
But when the APU ingests any fluid... deicing fluid or engine oil or hydraulic fluid, this can contaminate the cabin air. The smell sticks to the water separator bags.

We have had many oil smell events over the last couple of years, even though we are a cargo airline. Not every event makes it to the public because there are no pax to complain about the smell or a return.
Guess what, some pilots are concerned about their health as well. Not everything might have been dangerous, but rather be safe than sorry.

Horstroad wrote:

We have had many oil smell events over the last couple of years, even though we are a cargo airline.

There you go. It must be a cargo thing.

I wouldn't know about that.

Horstroad wrote:

Guess what, some pilots are concerned about their health as well.

You don't say? Which ones?

RJMAZ wrote:

T54A wrote:

This is striking given the low rates of overweight and smoking in this occupational group."

That wouldn't have anything to do with the high cholesterol intake, constantly eating out, airport food, high alcohol intake, promiscuous sex, solar radiation, and numerous other possibilities? It's got to be this mysterious, falsified "aerotoxic syndrome" conspiracy.

For a legitimate threat, why are the websites and videos full of such blatant, false information and lies? Hardly scientific.

747Whale wrote:

Horstroad wrote:

Guess what, some pilots are concerned about their health as well.

You don't say? Which ones?

Lots of them.

Based on your attitude here you probably carry that same attitude into the workplace. If you are in the airline industry no one will approach you saying they have a concern on fumes.

You sound like guy that would give the management a heads up so they could fire the pilots that raise concern. You can keep towing the company line but if you get sick they will also kick you to the kerb.

RJMAZ wrote:

747Whale wrote:

Lots of them.

Based on your attitude here you probably carry that same attitude into the workplace. If you are in the airline industry no one will approach you saying they have a concern on fumes.

You sound like guy that would give the management a heads up so they could fire the pilots that raise concern. You can keep towing the company line but if you get sick they will also kick you to the kerb.

You don't know me, and don't know my qualifications, but just so we're on an equal footing, how many decades experience do you have as a pilot? Mechanic? Engineer? Instructor? Inspector? Working for an airline? Flying large aircraft? Working on, using, maintaining, teaching pneumatic systems? How many thousand hours do you have in pressurized aircraft? Type rated in quite a few, lots of experience in them? So long as you're going to lecture me on that, you see.

You certainly don't sound like you fit any of those categories. You're going to lecture me about how I might behave on the job as a pilot or mechanic? Check airman? Instructor? Inspector?

This is an apologist tactic. When one's conspiracy theory is threatened by reality, attack the messenger.

Why is it that these conspiracy sites, aerotoxic.org, etc, are full of lies, mistruth, misrepresentation, etc? Say, for example, partial quotes from the "medical" article previously mentioned. No association indicated whatsoever with "aerotoxic syndrome," though the article does tie those conditions to "combined sources of circadian disruption." Go figure. The article was referenced to support "aerotoxic syndrome," yet conveniently left out the relevant parts that tied it to other causes. Again, a lie. Something that conspiracy theorists do. It also referenced the balance in cancers in male as heavily weighted toward high levels of second hand smoke. Someone forgot to quote that part, didn't they? The article mentions cosmic ionizing radiation. That seems to have been glossed over.

Perhaps most notable in that treatise is the statement regarding conclusions to be drawn:

The cross-sectional, observational nature of the study does not allow for conclusions about cause and effect. The authors also caution that health outcomes were based on self-reported data that could not be validated through medical records due to the associated scope and cost. The authors point out that US flight crew are subject to fewer protections than most workers in this industry, which may limit the generalizability of the results.

https://m.medicalxpress.com/news/2018-0 ... ation.html

Imagine that.

Study Summary.
The study does not use scientific methodology in any way shape or form to collect "data" and without any meaningful data the researchers are trying to prove an assumption that is pulled out of thin air.

They must have a connection with California's prop 65 where anything that is matter or energy causes cancer even if it can't be proven to.

747Whale wrote:

How do you suppose hydraulic fluid gets into the cabin atmosphere?

Through the pneumatic system. If a reservoir is over-serviced, there is a possibility that fluid can contaminate the air-conditioning system. Seen it a few times on the classic jumbos.

While I don't have access to the old Jumbo AMM, I still have access to the B757. From the "Smoke or Fumes Cabin Conditional Inspection":

(3) Smoke and fumes from Hydraulic System Contamination can be caused by:
(a) An over-serviced Hydraulic System

(b) Do a check for leaks or for evidence of Over-Servicing the Hydraulic System.
NOTE: Hydraulic fluid can go into the Pneumatic Ducts through the Hydraulic System Pressurization Line when over-serviced.

(c) Petroleum Jelly that is used during maintenance of the Pneumatic Ducts or Air Distribution Ducts.

Strangely, the B767 AMM doesn't address hydraulic fluid contamination in chapter 05. The B744 does address it in detail...again, from the reservoir pressurization modules. Neither the A300 nor the MD11 have a specific task for isolating the source of fumes.

So, yes, it is possible to get hydraulic fluid contamination in the cabin air.

One of the great things about the 787 is that head pressure on the hydraulic reservoir is not maintained by bleed air pressure because the hydraulic reservoirs are bootstrap reservoirs much like on a DC 10.



Another great thing is that the ECS system does not use bleed air because the 787 is essentially a bleedless aircraft. So like it or not, manufacturers have thought of ways to eliminate contamination to the conditioned air in the aircraft's cabin.

Not arguing for “aerotoxic syndrome” at all, but an example of how an apu can introduce smells/fumes into the cabin. Awhile back a md11 crew complained of fuel smell during preflight. The apu and packs were running. When I went back to the tail, fuel was leaking from the #2 drain mast and the wind was right to make it run down the belly to the inlet of the apu. It was entering the compressor and getting blown into the ducts. Had to correct the leak and change coalescer bags and run the packs for awhile to clear the smell. The 10/11 apu inlet is in a bad spot. Any leaks from the tail run down the belly. Which isn’t usually a problem. But that day it was.

I agree with stratclub, the dirty sock smell can usually be traced to some nasty coalescer bags or cabin air filters.

The APU is rarely, if ever, run in flight. The scent is not the same as "fumes" and aerotoxic syndrome, nor is overservice a standard, common thing, nor something that becomes an issue enroute on flights, and in most aircraft, there's no path from hydraulics to pneumatics.

The suggestion that crews are getting sick, or passengers sick from exposure to hydraulic fluid in pressurization systems and engine bleed, air, especially chronically over long periods of time, is ridiculous.

"Head pressure" for a hydraulic resorvoir doesn't contaminate the bleed air system with hydraulic fluid when bleed air is used. Bleed is tapped off the pneumatic system to various customers, which may include hydraulic resorvoirs, potable water, anti-ice or de-ice, etc. Not a problem.

747Whale wrote:

The APU is rarely, if ever, run in flight. The scent is not the same as "fumes" and aerotoxic syndrome, nor is overservice a standard, common thing, nor something that becomes an issue enroute on flights, and in most aircraft, there's no path from hydraulics to pneumatics.

But it is run on ground. Usually with crew/pax on board. The smell collects in the coalescer bags and can be noticeable for hours. Do you have the expertise to say for certain that this is only a smell and no toxins?
On most aircraft this might not be a problem. But on some it very well might be. I have the feeling that these events happen more often on A320 aircraft.

747Whale wrote:

The suggestion that crews are getting sick, or passengers sick from exposure to hydraulic fluid in pressurization systems and engine bleed, air, especially chronically over long periods of time, is ridiculous.

Smoking doesn't kill anybody right away. Even some heavy smokers never get lung cancer. But you wouldn't say this isn't bad either, right? The body might be able to deal with small amounts of bad cabin air. But an overdose or several high exposures surely are dangerous.
It's not a big deal to have fuel or hydraulic fluid or engine oil on your skin for a few minutes. After half an hour it will start to itch. After an hour or two it will burn. it will continue to burn and tingle even after you have washed it all off. Your skin will get dry. After very long exposure your skin will peel of the next day. I have older colleagues who are permanently ill because of benzol/benzene in their blood due to exposure in times where personal protection didn't have such a high priority.
Don't tell me this stuff isn't dangerous.
And I very well hope you only fly cargo aircraft because I wouldn't want to be a passenger on an aircraft with a pilot in command with such an attitude towards possible health issues.

747Whale wrote:

"Head pressure" for a hydraulic resorvoir doesn't contaminate the bleed air system with hydraulic fluid when bleed air is used. Bleed is tapped off the pneumatic system to various customers, which may include hydraulic resorvoirs, potable water, anti-ice or de-ice, etc. Not a problem.

It amazes me how one can be so stubborn. Even the manufacturer says this is a possibility as seen above. But you must be right, obviously.

747Whale wrote:

"Head pressure" for a hydraulic resorvoir doesn't contaminate the bleed air system with hydraulic fluid when bleed air is used. Bleed is tapped off the pneumatic system to various customers, which may include hydraulic resorvoirs, potable water, anti-ice or de-ice, etc. Not a problem.

So, Boeing is wrong? We’ve changed plenty of lines and ducts for hydraulic fluid contamination due to a failure on the classic.

What about Airbus? A very common problem on our A300 is a failure of the reservoir pressurization check valves. Of course, we get a reservoir pressure light (always seems to be the Blue system, but I digress), but every now and again, accompanying the light, is the “fumes” or “odor” complaint. In which case, all the check valves are replaced, as opposed to just the offending one, because it takes 2 check valves to fail to provide an opportunity for hydraulic fluid to contaminate the pneumatic system.

Horstroad wrote:

I have the feeling that these events happen more often on A320 aircraft.

There you go. We've gone from conspiracy sites and videos full of lies and misdirection to what you "feel" might be the case.

Glad it's science based, because a scary feeling trumps all. Maybe rather than pushing the all-transport category lie, just focus on frightening the airbus crowd, then. The crews, after all, are dropping like flies.

I'm especially interested in that Ozzie sick pilot in the captain seat with two stripes. Very impressive. And scary.

Horstroad wrote:

And I very well hope you only fly cargo aircraft because I wouldn't want to be a passenger on an aircraft with a pilot in command with such an attitude towards possible health issues.

It's a shame that the HR and training departments at each of my employers haven't had the benefit of you there to ensure that I'm kept out of the cockpit to keep the public safe, but perhaps you're put here on this earth to keep the public safe from aerotoxic syndrome, and everyone else has just been blind to my incompetence these last few decades.

I appreciate your judgement. It's always a pleasure to be condemned by the unqualified. Thank you.

It's almost as satisfying as those who opine that they're not qualified or experienced in these matters, but that they'd "never be a pilot" because they want to avoid the chronic exposure to that thing they know nothing more about than what they've read on falsified youtube videos and conspiracy websites.

Horstroad wrote:

But you must be right, obviously.

I am.

747Whale wrote:

It's just not a problem.

It's not that MUCH of a problem. I think this is why the B787's bleed system eliminated direct engine Bleed air for Air conditioning. one of the Worst fears of Maintenance is a hydraulic leak of Phosphate Esther hydraulic fluid seeping into the Air conditioning system from hydraulic lines running through the Air conditioning bay. The systems shouldn't effect each other but it is not unheard of for a line to develop a leak and foul one of the Air cycle machines. On the A320/A319 it sometimes comes from the Forward Cargo door Selector Valve which is located Below the cargo floor forward of the Air conditioning bay.. This has led us many times to the Problem just having this symptom. It's not something you can fix later as it's a pain in the Butt to get to in the first place and the cleanup can be extensive if it IS leaking.
Boeing did it right with the B787 eliminating the Engine Bleed air cycle system from the equation. Airbus is doing it with Solid hydraulic lines with no screw on connectors in that area. Now if they'd just get electric Cargo DOOR actuators? It might eliminate that particular problem altogether..

The reason the 787 doesn't use bleed air for the ECS system is because there is none available for it. Except for TAI (Thermal Anti Ice) and ACC (Active Clearance Control) for the engines, the 787 is a bleedless aircraft. I guess the Aerotoxic Syndrome lunatic fringe will have to chase other "there trying to kill us" conspiracies on the 787.
https://en.wikipedia.org/wiki/Aerotoxic_syndrome

So exactly what hydraulic lines run through the ECS bays on any aircraft and if hydraulic lines were present, how would a hydraulic leak get into sealed pressurized components ((ACM etc.) or ducting inside the ECS bays?

stratclub wrote:

The reason the 787 doesn't use bleed air for the ECS system is because there is none available for it. Except for TAI for the engines, the 787 is a bleedless aircraft.

So exactly what hydraulic lines run through the ECS bays and if so how would a hydraulic leak get into sealed pressurized component ((ACM) or ducting inside the ECS bay?

there are Hydraulic lines routed above the ACMs for the fwd and aft cargo doors. and the Fwd cargo door selector valve is below the waterline, as well as the reverser hydraulic lines which also transit the same bay along the ceiling of the AC bay. It's happened a few times where we found the leak just by opening the Fwd cargo door and watching it Bleed down. This was after we got a pilot report of acrid smell in the cabin. We very soon knew just where to look and we corroborated the faults with both Northwest and USAir as we all shared a LOT of Troubleshooting information for the Airbus A320/A319's. We all had different engines on ourA320's but the mechanical stuff? was a pretty good info group. And Airbus corroborated the Faults in their TSM. I worked as an Airbus Maintenance controller for United and our Data Base was pretty extensive, That was then and is now a pretty sharp group of guys. They're probably still headed by Pete Mastronouzzi and Craig Linkinhoker in Chicago right downtown today. (though I am now retired)

strfyr51 wrote:

stratclub wrote:

The reason the 787 doesn't use bleed air for the ECS system is because there is none available for it. Except for TAI for the engines, the 787 is a bleedless aircraft.

So exactly what hydraulic lines run through the ECS bays and if so how would a hydraulic leak get into sealed pressurized component ((ACM) or ducting inside the ECS bay?

there are Hydraulic lines routed above the ACMs for the fwd and aft cargo doors. and the Fwd cargo door selector valve is below the waterline, as well as the reverser hydraulic lines which also transit the same bay along the ceiling of the AC bay. It's happened a few times where we found the leak just by opening the Fwd cargo door and watching it Bleed down. This was after we got a pilot report of acrid smell in the cabin. We very soon knew just where to look and we corroborated the faults with both Northwest and USAir as we all shared a LOT of Troubleshooting information for the Airbus A320/A319's. We all had different engines on ourA320's but the mechanical stuff? was a pretty good info group. And Airbus corroborated the Faults in their TSM. I worked as an Airbus Maintenance controller for United and our Data Base was pretty extensive, That was then and is now a pretty sharp group of guys. They're probably still headed by Pete Mastronouzzi and Craig Linkinhoker in Chicago right downtown today. (though I am now retired)

That cleanup was a Pain in the Butt
the first time we found it? The hydraulic fluid had seeped into the inlet of the RT ACM from the Reverser line having been chafed, Another time it was a seep from the Fwd cargo door selector Valve and once it came from the Fwd cargo door opening actuator which was a REAL big clean-up.. Hell! I wish I could have made this stuff up.. If you were ever to need information like that? I'd call United American's Delta's Jet Blue's or Alaskan's Maintenance control. Or your local FAA ADCO,
They never had a problem calling us for information. And? What was I going to say? No I can't tell you? Fat Chance of That!! I want to be as helpful as I can including waking up somebody in Engineering to help them if I was on the evening shifts.

MY bad. your referring to Airbus. Boeing confines the TR plumbing to the strut because each engine only powers it's own TR so there is no need to provide hydraulic pressure to engines on the opposite wing. If you have a dead engine, why would you need a TR on that engine? If the EDP on any engine crapped out you would still have an ACMP or ADP available for each TR if the engine was still running and you need revers thrust.

The 787 cargo doors have their own self contained low pressure hydraulic systems that do not have power available to the pumps if the doors are latched. There are no external pressure or return lines that penetrate the pressure vessel of the aircraft.

Any aircraft has it's own design quirks though. There are some design "features" on just about any Boeing that make you wonder what were they thinking. On the 777 they had this computer generated virtual man called Catia Man that was used to validate access for maintenance procedures in Catia.

Well, on the 787, they must have taken poor old Catia Man out behind the virtual blast fence and shot him. Access for maintenance on a 787 can be kind of dismal sometimes.

747Whale wrote:

Horstroad wrote:

I have the feeling that these events happen more often on A320 aircraft.

There you go. We've gone from conspiracy sites and videos full of lies and misdirection to what you "feel" might be the case.

Glad it's science based, because a scary feeling trumps all. Maybe rather than pushing the all-transport category lie, just focus on frightening the airbus crowd, then. The crews, after all, are dropping like flies.

But the AviationHerald is probably just a conspiracy website.

Ah, we're back to "fumes," that generic statement that could be anything...a scent, smoke in the cabin, anything.

Smoke in the cabin could be an electrical fire, or any other number of sources.

Isolated cases of smoke in the cabin or "fumes," which are often little more than a scent, do not point to "aerotoxic syndrome."

This is the notion of conspiracy minded people, however...post a list of incidents involving smoke or other situations, and suddenly it's a chronic condition that's endemic to the industry, killing crews wholesale, and a threat to the entire air traveling planet.

A few isolated instances of smoke on an airbus do not equate to "aerotoxic syndrome," nor to the chronic threat that it purports to be. Citing aviaitonherald isn't proof, nor anything other than a list of possible incidents with zero background, and furthermore, in your case it's plagiarism, given your lack of citation, and you didn't even bother to print the material, just what appears to be part of a screen shot. Another case of zero credibility, but this is what conspiracists do. Present partial bits of information that they think fits their cause, and call it proof.

Each of these examples, the ones for which you didn't bother to lift a finger other than a half-hearted "search for fume," did you bother to review the actual reports for a single one of them?

747Whale wrote:

Ah, we're back to "fumes," that generic statement that could be anything...a scent, smoke in the cabin, anything.

Smoke in the cabin could be an electrical fire, or any other number of sources.

Yes a fume can be anything. But there are ovens that could stink on all aircraft. Yet these fume events seem to happen more often on A320 series aircraft. That's all I wanted to show with this screenshot. I didn't intend to prove that every fume event is toxic or that A320 are dangerous or anything else.
But you got so hung up on the word "feel" that i felt the necessity to show where this feeling comes from.

747Whale wrote:

did you bother to review the actual reports for a single one of them?

Yes I did read many of them. Out of curiosity though, not to fight a war for or against aerotoxic syndrome.

I'm not that deep into the matter. I'm not an expert. But I do work with these substances on a daily basis. And they are indeed toxic. They have an effect when in contact with your skin or eyes or when you get this stuff in your mouth.
And then there comes you saying "it's just not a problem" inhaling it. That's what's wrong for me.

Not all fume events are linked to aerotoxic syndrome. I have never said that.
Please read again what I said about repeated high exposure and overdose in my previous post. All I say is people can get sick from bad cabin air, not that it is a usual thing.

Horstroad wrote:

Yes a fume can be anything. But there are ovens that could stink on all aircraft. Yet these fume events seem to happen more often on A320 series aircraft. That's all I wanted to show with this screenshot.

And yet, you didn't.

Horstroad wrote:

Yes I did read many of them. Out of curiosity though, not to fight a war for or against aerotoxic syndrome.

What did you learn, and how does that support "aerotoxic syndrome?"

This IS a thread about aerotoxic syndrome, is it not?

Horstroad wrote:

I'm not that deep into the matter. I'm not an expert. But I do work with these substances on a daily basis. And they are indeed toxic. They have an effect when in contact with your skin or eyes or when you get this stuff in your mouth.
And then there comes you saying "it's just not a problem" inhaling it. That's what's wrong for me.

I work with all these things on a daily basis, too, and have for nearly 40 years.

That is entirely irrelevant to the concept of "aerotoxic syndrome." It's not a problem: "aerotoxic syndrome" does not exist. It is not a presence or a threat in cabin air. While there may be isolated cases of smoke in the cabin, that does not represent a chronic problem with a constant threat.

I did not say there is no problem inhaling chemicals. This is a figment of your imagination, and you attribute to me what I did not say. You have just lied, again.

"Aerotoxic syndrome" is not a problem, as it does not exist.

Scaremongering in an attempt to float conspiracy sites and videos, and half-screen shots without citation or reference, or even the insinuaiton that because you were work harmful chemicals, these chemicals are found in cabin air, is a lie, is scaremongering, and is nothing more than bald-faced sensationalistic melodrama without a root in science and barely qualifies for a bad straw-man argument.

747Whale wrote:

Horstroad wrote:

Yes a fume can be anything. But there are ovens that could stink on all aircraft. Yet these fume events seem to happen more often on A320 series aircraft. That's all I wanted to show with this screenshot.

And yet, you didn't.

Horstroad wrote:

Yes I did read many of them. Out of curiosity though, not to fight a war for or against aerotoxic syndrome.

What did you learn, and how does that support "aerotoxic syndrome?"

This IS a thread about aerotoxic syndrome, is it not?

Horstroad wrote:

I'm not that deep into the matter. I'm not an expert. But I do work with these substances on a daily basis. And they are indeed toxic. They have an effect when in contact with your skin or eyes or when you get this stuff in your mouth.
And then there comes you saying "it's just not a problem" inhaling it. That's what's wrong for me.

I work with all these things on a daily basis, too, and have for nearly 40 years.

That is entirely irrelevant to the concept of "aerotoxic syndrome." It's not a problem: "aerotoxic syndrome" does not exist. It is not a presence or a threat in cabin air. While there may be isolated cases of smoke in the cabin, that does not represent a chronic problem with a constant threat.

I did not say there is no problem inhaling chemicals. This is a figment of your imagination, and you attribute to me what I did not say. You have just lied, again.

"Aerotoxic syndrome" is not a problem, as it does not exist.

Scaremongering in an attempt to float conspiracy sites and videos, and half-screen shots without citation or reference, or even the insinuaiton that because you were work harmful chemicals, these chemicals are found in cabin air, is a lie, is scaremongering, and is nothing more than bald-faced sensationalistic melodrama without a root in science and barely qualifies for a bad straw-man argument.

You're right... it's TOTAL conspiracy theory....

http://www.euro.who.int/__data/assets/p ... om_ENG.pdf

Horstroad wrote:

747Whale wrote:

The APU is rarely, if ever, run in flight. The scent is not the same as "fumes" and aerotoxic syndrome, nor is overservice a standard, common thing, nor something that becomes an issue enroute on flights, and in most aircraft, there's no path from hydraulics to pneumatics.

But it is run on ground. Usually with crew/pax on board. The smell collects in the coalescer bags and can be noticeable for hours. Do you have the expertise to say for certain that this is only a smell and no toxins?
On most aircraft this might not be a problem. But on some it very well might be. I have the feeling that these events happen more often on A320 aircraft.

747Whale wrote:

The suggestion that crews are getting sick, or passengers sick from exposure to hydraulic fluid in pressurization systems and engine bleed, air, especially chronically over long periods of time, is ridiculous.

Smoking doesn't kill anybody right away. Even some heavy smokers never get lung cancer. But you wouldn't say this isn't bad either, right? The body might be able to deal with small amounts of bad cabin air. But an overdose or several high exposures surely are dangerous.
It's not a big deal to have fuel or hydraulic fluid or engine oil on your skin for a few minutes. After half an hour it will start to itch. After an hour or two it will burn. it will continue to burn and tingle even after you have washed it all off. Your skin will get dry. After very long exposure your skin will peel of the next day. I have older colleagues who are permanently ill because of benzol/benzene in their blood due to exposure in times where personal protection didn't have such a high priority.
Don't tell me this stuff isn't dangerous.
And I very well hope you only fly cargo aircraft because I wouldn't want to be a passenger on an aircraft with a pilot in command with such an attitude towards possible health issues.

747Whale wrote:

"Head pressure" for a hydraulic resorvoir doesn't contaminate the bleed air system with hydraulic fluid when bleed air is used. Bleed is tapped off the pneumatic system to various customers, which may include hydraulic resorvoirs, potable water, anti-ice or de-ice, etc. Not a problem.

It amazes me how one can be so stubborn. Even the manufacturer says this is a possibility as seen above. But you must be right, obviously.

Yeah, you are right. That is a terrible apologist denial of something very real. He would fit right in with the leaded fuel is safe crowd, vaping is safe, smoking is ok crowd.

Whale, I'm highly educated in science, with multiple degrees in science. I also studied this problem while in the USAF, which I assure you spends more money on these things than any cargo outfit. I also fly big airplanes like you might. The difference is that I can intelligently read scientific literature and see strong empirical correlations and understand the chemical equations. You really should educate yourself substantially more on the topic before being in flat denial. And, if you don't want to do that, then study how corporations have done all kinds of reprehensible things to people over the years from things like this. Study pollution in general.

greendot wrote:

747Whale wrote:

Horstroad wrote:

Yes a fume can be anything. But there are ovens that could stink on all aircraft. Yet these fume events seem to happen more often on A320 series aircraft. That's all I wanted to show with this screenshot.

And yet, you didn't.

Horstroad wrote:

Yes I did read many of them. Out of curiosity though, not to fight a war for or against aerotoxic syndrome.

What did you learn, and how does that support "aerotoxic syndrome?"

This IS a thread about aerotoxic syndrome, is it not?

Horstroad wrote:

I'm not that deep into the matter. I'm not an expert. But I do work with these substances on a daily basis. And they are indeed toxic. They have an effect when in contact with your skin or eyes or when you get this stuff in your mouth.
And then there comes you saying "it's just not a problem" inhaling it. That's what's wrong for me.

I work with all these things on a daily basis, too, and have for nearly 40 years.

That is entirely irrelevant to the concept of "aerotoxic syndrome." It's not a problem: "aerotoxic syndrome" does not exist. It is not a presence or a threat in cabin air. While there may be isolated cases of smoke in the cabin, that does not represent a chronic problem with a constant threat.

I did not say there is no problem inhaling chemicals. This is a figment of your imagination, and you attribute to me what I did not say. You have just lied, again.

"Aerotoxic syndrome" is not a problem, as it does not exist.

Scaremongering in an attempt to float conspiracy sites and videos, and half-screen shots without citation or reference, or even the insinuaiton that because you were work harmful chemicals, these chemicals are found in cabin air, is a lie, is scaremongering, and is nothing more than bald-faced sensationalistic melodrama without a root in science and barely qualifies for a bad straw-man argument.

You're right... it's TOTAL conspiracy theory....

http://www.euro.who.int/__data/assets/p ... om_ENG.pdf

The very first sentence of the introduction of the linked study is bogus for modern aircraft. The bleed air in modern gas turbine aircraft is in fact filtered. We do not fly revenue flights on 50's era military aircraft.

Are you a Prop 65 "Scientist"? If you are going to argue something at least argue with facts that are relevant today.

https://en.wikipedia.org/wiki/Environme ... d_air_unit
EXTRACT: The air is then sent through a water separator, where the air is forced to spiral along its length and centrifugal forces cause the moisture to be flung through a sieve and toward the outer walls where it is channeled toward a drain and sent overboard. Then, the air usually will pass through a water separator coalescer or the sock. The sock retains the dirt and oil from the engine bleed air to keep the cabin air cleaner. This water The air is then sent through a water separator, where the air is forced to spiral along its length and centrifugal forces cause the moisture to be flung through a sieve and toward the outer walls where it is channeled toward a drain and sent overboard.

Then, the air usually will pass through a water separator coalescer or the sock. The sock retains the dirt and oil from the engine bleed air to keep the cabin air cleaner. This water removal process prevents ice from forming and clogging the system, and keeps the cockpit and cabin from fogging on ground operation and low altitudes.emoval process prevents ice from forming and clogging the system, and keeps the cockpit and cabin from fogging on ground operation and low altitudes.

stratclub wrote:

Then, the air usually will pass through a water separator coalescer or the sock. The sock retains the dirt and oil from the engine bleed air to keep the cabin air cleaner.

The coalescer is not a proper filter. It is just a piece of cloth. Its function is to collect condensed water, not to filter the air.
It certainly will filter out some "bigger" particles. You can see that as they are always very black when you replace them.
They might be able to filter oil mist. But certainly not vaporized oil.

Also trim air does not run through these socks