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Boeing whistleblower raises doubts over 787 oxygen system

bbc.com

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Re: Boeing whistleblower raises doubts over 787 oxygen system

#201

Post by inferiorhuman »

mopsi wrote: post #199
inferiorhuman wrote: post #194

Earlier quoted context omitted.

Not at all. Its malfunctions are clear and obvious. While the FAA seems to agree with you EASA, Transport Canada, Australia's ATSB, and Senegal's BEA seem to disagree.

Of course alerting could and was improved, but the Turkish accident wouldn't have happened if pilots had done the bare minimum of what's expected of them and monitored airspeed and altitude while they were flying close to ground and preparing to land any minute. As said, autothrottle malfunction is a known unknown (with or without radio altimeter), something one can reasonably expect to happen, unlike the recent Airb…

Of course alerting could and was improved, but the Turkish accident wouldn't have happened if pilots had done the bare minimum of what's expected of them and monitored airspeed and altitude while they were flying close to ground and preparing to land any minute.

The TAM wreck wouldn't have happened had the pilots flown the plane either. vOv

unlike the recent Airbus case where a bumpy landing led to loss of flight controls, something no pilot was trained for nor could reasonably expect to happen.

That was quite a bit more than a bumpy landing. The Lufthansa pilots touched down far past where they should've. That's not a flaw with the aircraft. There's a reason the formal conclusion was pilot error and not because nationalism came into play.

What's also important to stress is that loss of radio altimeter and autothrottle did not restrict Boeing pilots in any way. They had full control over the aircraft.

Don't forget that in some of these cases, the autopilot didn't disconnect because the autopilot couldn't determine that one of the RAs had failed.

And what of the Lauda Air wreck? How much control did the pilots have when the reversers deploy in flight on a 76?

How about asymmetric flap deployments on a 75? Capt. VanderBurgh already discussed that scenario — another one where Boeing said that could never happen and pilots shouldn't train in the sim for it. Turns out it can happen and you're basically SOL.

Or what of the rudder hard overs in the NG?

How about the Helios Air wreck where the alarm for takeoff config and pressurization problems was (and still is) the same? How much awareness do you think a hypoxic crew will have?

How about the AoA disagree annunciator on the MAX that was too buggy to work unless you paid for additional features? Plenty of low quality crap comes out of Boeing these days…

Re: Boeing whistleblower raises doubts over 787 oxygen system

#202

Post by vijayr02 »

jkachmar wrote: post #177
vijayr02 wrote: post #173

Earlier quoted context omitted.

Thanks, yes, I've heard that NTSB crash reports are mind blowing in their attention to detail. A follow on question: how do they ensure people honestly answer questions, is the person not inviting personal liability by answering?

In my experience there has always been a _deep_ culture of mutual respect between industrial aviation players and the NTSB. Everyone knows that the investigative body is there to help figure out what went wrong and to provide guidance on how to avoid similar mistakes in the future. It’s not about assigning blame, and there’s an understanding that if it were to become about that then the industry would be worse-off as…

Thank you both for the answers!

Re: Boeing whistleblower raises doubts over 787 oxygen system

#203

Post by WrtCdEvrydy »

rosybox wrote: post #181
MSeven wrote: post #110

Earlier quoted context omitted.

Just last week i heard a story from an older friend about a fighter jet crash investigation he was involved in, where the cause basically was that an engineer wired down some bolts (as required) but trimmed the ends of the wires without recovering the trimmed part. That little piece eventually found its way into the main stick mechanics, causing enough resistance at the wrong moment, preventing the pilot from recover…

I am really impressed that we are able to fly safely at all if a tiny little piece of debris like this can cause plane crashes. Debris is a fact of life. Things fall apart, small pieces come off whatever substance or piece they were attached to. Are maintenance crews constantly just taking aircraft apart and vacuuming every surface they find?

Military aircraft are designed to be unstable, so that they can perform fast, odd combat maneuvers. The flight computers are the only think keeping those things flying.

Civilian aircraft are designed to be super stable.

Re: Boeing whistleblower raises doubts over 787 oxygen system

#204

Post by hollerith »

WrtCdEvrydy wrote: post #203
rosybox wrote: post #181

Earlier quoted context omitted.

I am really impressed that we are able to fly safely at all if a tiny little piece of debris like this can cause plane crashes. Debris is a fact of life. Things fall apart, small pieces come off whatever substance or piece they were attached to. Are maintenance crews constantly just taking aircraft apart and vacuuming every surface they find?

Military aircraft are designed to be unstable, so that they can perform fast, odd combat maneuvers. The flight computers are the only think keeping those things flying. Civilian aircraft are designed to be super stable.

And aerodynamic stability would not have prevented the accident described in grandparent.

Re: Boeing whistleblower raises doubts over 787 oxygen system

#205

Post by WrtCdEvrydy »

vijayr02 wrote: post #202
jkachmar wrote: post #177

Earlier quoted context omitted.

In my experience there has always been a _deep_ culture of mutual respect between industrial aviation players and the NTSB. Everyone knows that the investigative body is there to help figure out what went wrong and to provide guidance on how to avoid similar mistakes in the future. It’s not about assigning blame, and there’s an understanding that if it were to become about that then the industry would be worse-off as…

Thank you both for the answers!

Look at the original metal fatigue investigations that lead to round windows.

They pressurized and depressurized an airplane (inside of a water tank) 50,000 times until it failed.

Re: Boeing whistleblower raises doubts over 787 oxygen system

#206

Post by mopsi »

inferiorhuman wrote: post #197
mopsi wrote: post #193

Earlier quoted context omitted.

In TAM and LH cases, pilots were locked out of using full braking capabilities of the aircraft because they found themselves in a situation that didn't satisfy the conditions defined as "landing" by aircraft designers. The had wheels on the ground, but program logic evaluated to onground = FALSE. Westjet and Turkish incidents are irrelevant. Westjet malfunctioned, pilot took control and landed safely - that's what pi…

The had wheels on the ground, but program logic evaluated to onground = FALSE. Nope. The Lufthansa bird had one bogie on the ground and one off. With the TAM flight the pilots left one thrust lever at climb power and one at idle, pure pilot error. The Westjet and Turkish incidents are irrelevant. Westjet malfunctioned, pilot took control and landed safely - that's what pilots are there for. Turkish airplane also malf…

> Nope. The Lufthansa bird had one bogie on the ground and one off.

Which is to be expected from a crosswind landing (especially with a lot of lift from higher-than-usual speed), but it took 900 m of runway before enough weight was detected on both of them to activate thrust reversers and spoilers. And even after all wheels were on the ground, it took another 300 m before wheel brakes became active. The accident investigation report recommended introduction of emergency override to cover the whole range of conditions in which airplanes fly.

> With the TAM flight the pilots left one thrust lever at climb power and one at idle, pure pilot error.

The aircraft was firmly on the ground, with one thrust lever in reverse position. Spoilers and auto-brake did not activate because position of the other lever lever was prioritized over actual condition of the aircraft. Critical data was derived from a thrust lever, which has no safety features to prevent inadvertent wrong positioning. Furthermore, lever positioning suppressed aural reminders to bring thrust levers to idle (the famous "RETARD").

> Unfortunately the 737s were functioning as designed, the computers took invalid input and ran with it instead of cross checking it.

Which is irrelevant on the 737, because its design philosophy expects pilots to monitor and (if necessary) override automation, which hundreds of attentive crews successfully did before the Turkish crash. A320, on the other hand, lacks emergency override, as the LH2904 investigators noted in their report. It cannot reliably tell whether the aircraft is on the ground or not, and stops pilots from taking the correct action.

Re: Boeing whistleblower raises doubts over 787 oxygen system

#207

Post by jMyles »

soapboxrocket wrote: post #137
jMyles wrote: post #2

Wow - more serious story than I first imagined. > Mr Barnett, a former quality control engineer, worked for Boeing for 32 years, until his retirement on health grounds in March 2017. From 2010 he was employed as a quality manager at Boeing's factory in North Charleston, South Carolina. This plant is one of two that are involved in building the 787 Dreamliner. In terms of credibility lent by a career, you can't do muc…

> Even if the bag does not inflate, breathe normally as oxygen is flowing. Or not. The 787 doesn't have any accumulator bags, the big difference with that system is that its electronically pulse controlled oxygen flow rather than a mechanical/chemical constant flow system. His claim isn't exactly true, the lab he used sent power to all systems at once, this is why he saw a failure of about 25%, in fact the system on…

Of course I was just riffing on the typical in-flight safety language, but I appreciate learning a bit more about the 787. I guess I never noticed this, but I imagine the safety video doesn't show (or mention) the bags?

Re: Boeing whistleblower raises doubts over 787 oxygen system

#208

Post by mopsi »

inferiorhuman wrote: post #201
mopsi wrote: post #199

Earlier quoted context omitted.

Of course alerting could and was improved, but the Turkish accident wouldn't have happened if pilots had done the bare minimum of what's expected of them and monitored airspeed and altitude while they were flying close to ground and preparing to land any minute. As said, autothrottle malfunction is a known unknown (with or without radio altimeter), something one can reasonably expect to happen, unlike the recent Airb…

Of course alerting could and was improved, but the Turkish accident wouldn't have happened if pilots had done the bare minimum of what's expected of them and monitored airspeed and altitude while they were flying close to ground and preparing to land any minute. The TAM wreck wouldn't have happened had the pilots flown the plane either. vOv unlike the recent Airbus case where a bumpy landing led to loss of flight con…

> The TAM wreck wouldn't have happened had the pilots flown the plane either.

Pilots were actively engaged, made a minor mistake by setting wrong thrust lever position on one engine, which caused the aircraft to disregard any other input and assume the aircraft to be airborne even when it was on the ground, spoilers and auto-braking armed, brakes manually slammed and one engine in reverse.

> That was quite a bit more than a bumpy landing.

I was referring to the 2018 incident. Pilots did everything by the book, yet lost elevator control.

> Don't forget that in some of these cases, the autopilot didn't disconnect because the autopilot couldn't determine that one of the RAs had failed.

Again, completely irrelevant as it did not prevent pilots from taking full control of the aircraft.

The rest of the examples you've thrown at me are also all malfunctions and have nothing to do with A320 incorrectly determining its state and overriding correct input from pilots.

Re: Boeing whistleblower raises doubts over 787 oxygen system

#209

Post by torgian »

cartoonworld wrote: post #144
gorgoiler wrote: post #143

Earlier quoted context omitted.

What is FOD in this context?

Foreign Object Debris

We always called it "Foreign Object Damage" but yeah, "Debris" would technically be more correct.

Gotta keep the FOD out of the aircraft and the flight lines!

Re: Boeing whistleblower raises doubts over 787 oxygen system

#210

Post by torgian »

WrtCdEvrydy wrote: post #203
rosybox wrote: post #181

Earlier quoted context omitted.

I am really impressed that we are able to fly safely at all if a tiny little piece of debris like this can cause plane crashes. Debris is a fact of life. Things fall apart, small pieces come off whatever substance or piece they were attached to. Are maintenance crews constantly just taking aircraft apart and vacuuming every surface they find?

Military aircraft are designed to be unstable, so that they can perform fast, odd combat maneuvers. The flight computers are the only think keeping those things flying. Civilian aircraft are designed to be super stable.

This isn't necessarily true. Without stability you can't perform certain maneuvers. And the large aircraft are super stable.

That said, we take FOD and tool control very seriously. And the aircraft had 30 / 60 / 90 /365 day inspections that varied in detail

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