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Masks, Smoke, and Mirrors: The story of EgyptAir flight 804

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Re: Masks, Smoke, and Mirrors: The story of EgyptAir flight 804

#131

Post by cyberax »

jabl wrote: post #75
cyberax wrote: post #40

Earlier quoted context omitted.

This really is a non-issue. If you're at the point where toxins from halon pyrolysis are a problem, then you're likely already dead from other factors (heat, smoke, etc.). Halon can works even at concentrations of just 2-5% by volume. This is entirely safe to breathe for humans. There's a video of a person discharging a halon extinguisher in a room, and then proceeding to try to light a cigarette. The matches go out…

Engine rooms in ships typically have CO2 systems. There's been several fatalities when crew have reentered the space before the CO2 has been ventilated away. Made worse by CO2 being heavier than air so it can remain in some crawlspace under the engine frame or such.

Yep. Found that safety video: https://youtu.be/NrP5-E9jmas?t=344 - I was misremembering it a bit.

It's really unfortunate that halon is so dangerous for the ozone layer, none of the replacements are as good as it was.

Re: Masks, Smoke, and Mirrors: The story of EgyptAir flight 804

#132

Post by singleshot_ »

ndiddy wrote: post #125
ec109685 wrote: post #107

Earlier quoted context omitted.

Besides not agreeing with the EAAID, nothing in then BEA report makes Egypt look bad. It was a tragic accident and the crew acted admirably. What was the motivation for Egypt to insist on a bomb detonation beyond them believing that is what happened?

The article and French report point to the fire being caused by an oxygen leak from a faulty cockpit oxygen mask system. There were many problems reported with the system on that plane, such as the oxygen air level decreasing every flight and the oxygen mask box being replaced with a refurbed faulty one from another plane after it was found to be stuck open. Additionally, there's allegations of other problems with th…

If an airline discovers that it has poor maintenance from an accident investigation, and tells everyone about the problem, then I _might_ consider flying that airline in the furure.

EgyptAir would be an extremely hard no for me.

Re: Masks, Smoke, and Mirrors: The story of EgyptAir flight 804

#133

Post by cyberax »

cyberax wrote: post #131
jabl wrote: post #75

Earlier quoted context omitted.

Engine rooms in ships typically have CO2 systems. There's been several fatalities when crew have reentered the space before the CO2 has been ventilated away. Made worse by CO2 being heavier than air so it can remain in some crawlspace under the engine frame or such.

Yep. Found that safety video: https://youtu.be/NrP5-E9jmas?t=344 - I was misremembering it a bit. It's really unfortunate that halon is so dangerous for the ozone layer, none of the replacements are as good as it was.

Second 292 for the demo.

Re: Masks, Smoke, and Mirrors: The story of EgyptAir flight 804

#134

Post by sterlind »

ddalex wrote: post #115
soapboxrocket wrote: post #5

Reminds me a bit of the UPS Flight 6 that crashed in 2010. Wasn't the cause of the fire, but the fire heated up the co-pilots oxygen system to the point he couldn't wear it and eventually succumbed to smoke hypoxia. Due to smoke in the cabin the pilot couldn't see his flight deck readouts or out the window and eventually crashed into the ground.

One would have to wonder why an emergency smoke extractor fan isn't default equipment - when pilots oxy is deployed a panel should blow outward and a high flow fan start.

blowtorch effect. depressurizing the cabin and cargo hold is on the checklist for some on-board fires, but the rushing air can produce a blowtorch and spread the fire along. see UPS flight 6 iirc.

Re: Masks, Smoke, and Mirrors: The story of EgyptAir flight 804

#135

Post by thedrbrian »

buildsjets wrote: post #120
dmckeon wrote: post #6

Tragedy from a Swiss cheese failure - several small holes/failures all line up. The issue of halon extinguishers versus oxygen-powered combustion producing many toxins while failing to extinguish is interesting - good that: > Halon fire extinguishers are scheduled to be phased out of most commercial aircraft by the end of 2025.

No, they are not. Source: me. Also here’s the applicable EU regulation. https://eur-lex.europa.eu/legal-content/EN/TXT/?uri=CELEX%3A... Only handheld portable extinguishers are required to be phased out in 2025, and only in locations that are regulated by EASA. The FAA does not give a rip, and neither to the many regulatory bodies around he world who defer tho the FAA. I don’t know what the CAAC is doing. As far as t…

>The F-16 inerts it’s fuel tank ullage space with Halon.

why can't they use nitrogen ?

Re: Masks, Smoke, and Mirrors: The story of EgyptAir flight 804

#136

Post by fransje26 »

amelius wrote: post #31

With all the high speed trains in Europe, I'm wondering why we don't see more security around them. It seems a much easier target than airplanes.

And what do you want to do with a high speed train?

They are equipped with a dead man switch, and will shutdown pretty much immediately if not responded to in time. Case in point: the high speed train driver that committed suicide by jumping out of his train two days ago. (May he rest in peace.) And ultimately, they are computer monitored, and will be shutdown if a given set of security procedures are not respected.

French trains have had bombs explode in them in the past, and did not derail. Some have hit landslides at full speed, and did not derail.

High-speed trains are fine, no need for airport-like obnoxious levels of "security".

Re: Masks, Smoke, and Mirrors: The story of EgyptAir flight 804

#137

Post by jabl »

cyberax wrote: post #131
jabl wrote: post #75

Earlier quoted context omitted.

Engine rooms in ships typically have CO2 systems. There's been several fatalities when crew have reentered the space before the CO2 has been ventilated away. Made worse by CO2 being heavier than air so it can remain in some crawlspace under the engine frame or such.

Yep. Found that safety video: https://youtu.be/NrP5-E9jmas?t=344 - I was misremembering it a bit. It's really unfortunate that halon is so dangerous for the ozone layer, none of the replacements are as good as it was.

High-pressure water mist systems seem pretty good, including being usable in spaces with lots of electrical stuff like machine rooms and data centers.

https://www.marioff.com/en/

Re: Masks, Smoke, and Mirrors: The story of EgyptAir flight 804

#138

Post by gus_massa »

selimthegrim wrote: post #128
elashri wrote: post #117

Earlier quoted context omitted.

> “[I] ask forgiveness from God.” That's too much reading by a western observer who doesn't understand the religious and cultural aspect of things. This could mean anything from "hoping that God will help us in this difficult situation by admitting your sins" to someone who realizes it is almost the end and as someone who believes in after death then they want to ask forgiveness in the last moments.

The last part of the sentence is correct, but the EgyptAir 990 crash gave it a bad cast in Western eyes.

Hi from Argentina! Am I Westener enough?

I think I don't have enough cultural and religious context, but they look like standard last words to say. (Moreover, they feel like last words indicate that the whole crew and passengers were unrelate for the cause of the accident, but perhaps I'm reading too much.)

Re: Masks, Smoke, and Mirrors: The story of EgyptAir flight 804

#139

Post by buildsjets »

thedrbrian wrote: post #135
buildsjets wrote: post #120

Earlier quoted context omitted.

No, they are not. Source: me. Also here’s the applicable EU regulation. https://eur-lex.europa.eu/legal-content/EN/TXT/?uri=CELEX%3A... Only handheld portable extinguishers are required to be phased out in 2025, and only in locations that are regulated by EASA. The FAA does not give a rip, and neither to the many regulatory bodies around he world who defer tho the FAA. I don’t know what the CAAC is doing. As far as t…

>The F-16 inerts it’s fuel tank ullage space with Halon. why can't they use nitrogen ?

Weight, and the small size of the aircraft. F-16s are tiny. It would take a LOT more stored nitrogen gas to dilute the O2 level below the upper explosive limit, than it takes of CF3Br to chemically interfere with combustion. Modern aircraft use continuous nitrogen gas separators that run off engine bleed air to accomplish the task, at the cost of some weight and a ~3-5% increase in fuel burn. There was a study to replace the CF3Br with CF3I back in the 1980s but it was shelved due to technical challenges, which could have been overcome with additional investment.

https://www.nist.gov/system/files/documents/el/fire_research...

Re: Masks, Smoke, and Mirrors: The story of EgyptAir flight 804

#140

Post by eadmund »

wussboy wrote: post #112
eadmund wrote: post #94

> there was no evidence that the pilots of flight 804 smoked during the flight. But even though the BEA found that a cigarette didn’t cause the fire on flight 804 … the BEA recommended that EASA examine these risks and amend regulations as necessary Smoking had nothing to do with this incident. Their own testing showed that holding a cigarette in the oxygen stream was (surprisingly) not dangerous. The only risk from…

This is the second pro smoking post I’ve seen of yours on this thread. A curious stance to take. Could a cigarette fall into the mask stowage box and rest against the oxygen tube thus creating a fire? Yes, it could. The entire and complete elimination of this risk is simply solved by forbidding the pilots from smoking, which is already forbidden to the entire cabin crew and passengers. What’s the big deal? Who is har…

> This is the second pro smoking post I’ve seen of yours on this thread. A curious stance to take.

I don’t particularly like cigarettes, but I love tobacco and I absolutely hate the moral panic over it.

> Who is harmed by not allowing pilots to smoke?

The pilots.

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