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

Really amazing work, read NTSB crash reports and they outline the methods used

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 a whole.

(Slightly off-topic, but this is precisely why Tesla’s reaction to the NTSB investigation in their Model X crash was so concerning. Any player that defects here runs the risk of poisoning the process for everyone else.)

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

Civilian aircraft are designed to be 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

Planes have to be predictable, they can have massive failure states but the solution must be repeatable. Unknown failures, regardless of the severity, are a major problem and should always be tracked and investigated. A small unknown failure could be a symptom or precursor to a much larger problem.

Everyone hates paperwork but it's what saves lives.

My neighbor is a pilot and I asked him completely off hand how to troubleshoot non responsive flaps and he went into detail about the hydraulics system, where the pumps are and the steps he would take to troubleshoot. This was off the top of his head without a checklist.

Boeing is maybe too big to fail, but the reputation hit they are taking may lead to companies not buying their planes, thus pushing for least competition, which is bad news for everyone.

Airbus being the kind of behemoth company it is, I am convinced that without Boeing's competition, over time, they would end up with the same practices, convinced that their aircraft sell themselves.

What happened there: wrong kind of oil was used in elevator and it went unnoticed because maintenance guides did not require any inspections of affected parts. Wrong oil caused delays in sensor triggering, which led to primary computers shutting down, believing that there was a problem with elevator.

Backup computers didn't detect gear compression correctly when the aicraft bounced on the runway (one computer believed it was on the ground, the other that it was airborne) and also shut down and locked the elevator in neutral (zero) position as a safety measure.

This happened during a touch-and-go landing on a training flight. The A320 touched down, bounced, elevator got locked, the aircraft climbed a bit, then fell down on the runway scraping and damaging engines (due to loss of control), then took off again (not enough runway left for stopping) and was now flying with no elevator and with engines about to shut down. It's a miracle that pilots managed to turn around and land safely.

In 1993, Lufthansa A320 crashed under similar conditions: landed in poor conditions, computers didn't think it was on the ground and didn't allow braking until it was too late https://en.wikipedia.org/wiki/Lufthansa_Flight_2904

What has surfaced in the last few months, is that Boeing is willing to cut corners, and is not being diligent. It's completly possible that the same thing is happening at Airbus, but I have not personnally seen or heard evidences of that. At the very least, Airbus is not certifying it's own planes.

For example, for the crash you mentionned, was Airbus aware of that potential issue sooner but didn't update the maintenance guide for some ulterior motives?

Maybe, but the report you linked does not show that. The issue with Boeing is not that a plane crashed but that planes crashed despite earlier reports that people considered these planes unsafe. No such reports came out of Airbus about the A320 as far as I'm aware. Also the regulators did not delegate certification to Airbus.

Boeing, in contrast, uses simple radar altimeter. Whenever altitude reads 10 feet or less, the aircraft is considered to be "on ground" and things like thrust reversers become available.

I personally avoid praising or preferring Airbus when bashing Boeing. Who knows what else is under that rock too.

Which is problematic and has killed 134 people.

https://www.flightglobal.com/news/articles/easa-cautions-737...

things like thrust reversers become available.

Boeing rather famously had a problem with in-air thrust reverse deployment (not on the 73 though).

Not at all. Its malfunctions are clear and obvious. If autothrottle starts moving thrust levers in unexpected ways, you turn the autothrottle off and assume manual control.

Thrust levers, reversers, braking or any other systems were not blocked or deployed unexpectedly. The aircraft simply reduced thrust too much while in control of speed, which is something one should always look out for, it's an expected failure, a known unknown.

The Turkish airplane crashed because the crew was flying an unstable approach and did not pay attention to warnings because their style of flying was expected to trigger warnings. This obscured the malfunction.

They came in too fast and too steep, ignored aural warnings, let thrust levers move to idle (which they expected because of high speed), failed to monitor airspeed and didn't notice last minute warnings because they were occupied with checklist that they should've already been through.

No-one was actually flying the airplane, despite the fact that there was an extra third safety pilot in the cockpit who was tasked with observing the flight.

While the FAA seems to agree with you EASA, Transport Canada, Australia's ATSB, and Senegal's BEA seem to disagree.

As said, autothrottle malfunction is a known unknown (with or without radio altimeter), something one can reasonably expect to happen, 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.

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.

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…

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.

You mentioned LH2904 and TAM3054. In both cases the pilots fucked up. Full stop.

Both flights were deemed pilot error by the respective investigative agencies. In the Lufthansa flight, they touched down too far down the runway.

A320 incorrectly determining its state and overriding correct input from pilots

The A320 pilots did not provide correct inputs.

This whole thread started from description of the 2018 SmartLynx accident.

> The A320 pilots did not provide correct inputs.

They did. Read the 2018 report. Simple touch-and-go's on a training day led to loss of elevator due to timing of a single light bounce after touchdown.

> Both flights were deemed pilot error by the respective investigative agencies.

Both reports also concluded that design of the aircraft contributed to the accident (instead of preventing) and recommended revising it.

In addition, the 2018 SmartLynx crash showed that the A320 still can't tell whether it's on the ground or not. This time pilots did everything by the book, and found themselves locked out of elevator control due to poor design of A320 SEC computers.

Yeah I'm familiar with the accident in question in passing so I just skimmed the article itself (whoops). RA failure on the 737 isn't unheard of:

https://avherald.com/h?article=4924e9ea (2015)

https://avherald.com/h?article=48c031e2 (2015)

https://avherald.com/h?article=4bc252c2 (2018)

https://avherald.com/h?article=417e726c (2009)

https://avherald.com/h?article=41e84cb5 (2009)

The in-flight thrust reverser deployment killed everyone on the plane, thankfully Niki Lauda took Boeing to task.

So you're claiming that Airbus knowingly leaves a critical defect in their planes, which may cause the loss of flight controls and which they refreain from fixing for almost 30 years?

Either come up with a reliable source for this statement (which is extremely hard to believe) or allow me to call bullshit!

A320's computers monitor gear for uncompression of 1 second or longer. Computers are not in sync. If landing gear decompresses due to bouncing for long enough to be seen for 1 second by one computer, but short enough to get missed by the other, computers will produce different outputs and the system will shut down, freezing important flight control at a dangerous phase of flight and leaving pilots in a situation they have not been trained for.

Given the very obviously flawed and incredibly poor design that's easy to understand even for laymen, I would have very hard time believing that no-one at Airbus ever noticed, no-one ever spoke up. I think this would reflect even more poorly on Airbus.

Especially so considering that there have been multiple hull-loss accidents with fatalities (LH2904, TAM3054), where air/ground detection has been a contributing factor. Throughout the years, the aircraft has been unable to tell whether it's on the ground or in the air.

With the Lufthansa flight the problem was not the aircraft design but rather that the pilot remained on only one main gear for too long. The Airbus design requires weight on both wheels (this had nothing to do with computers being out of sync) in order to prevent things like the Lauda Air (Boeing 767-300ER) crash where the thrust reversers deployed in flight causing the plane to drop out of the sky, killing everyone.

Same deal with the TAM flight. For whatever reason the pilots didn't properly position the thrust lever on one engine. That had nothing to do with computers being out of sync and had absolutely nothing to do with ground detection.

Meanwhile with the Boeing 737, a single (unreliable) radar altimeter (RA) is used as part of the ground detection and a single failed RA caused a Westjet 737 to start pulling back on the throttles.

http://avherald.com/h?article=41e84cb5

As far a the Turkish 737 crash:

http://avherald.com/h?article=41595ec3

During the accident flight, while executing the approach by means of the instrument landing system with the right autopilot engaged, the left radio altimeter system showed an incorrect height of -8 feet on the left primary flight display. This incorrect value of -8 feet resulted in activation of the ‘retard flare’ mode of the autothrottle, whereby the thrust of both engines was reduced to a minimal value (approach idle) in preparation for the last phase of the landing.

...

The problems with radio altimeter systems in the Boeing 737-800 fleet had been affecting several airlines, including Turkish Airlines, for many years and were known to Boeing and the Federal Aviation Administration of the United States of America.

...

Despite the fact that Boeing and the Federal Aviation Administration of the United States of America had been aware for many years that the radio altimeter system was causing many problems and was affecting the operation of other systems, this situation was not designated as a safety risk. Reports of problems with the radio altimeter system that could not be resolved by Boeing justified an effort to analyse the radio altimeter system and other related systems. Boeing and the Federal Aviation Administration of the United States of America could have recognised the fact that the problems caused by the radio altimeter system, especially the potential for activating the autothrottle retard flare mode, posed a safety risk.

That sounds a lot like the engineering that went into MCAS - using only one input for something safety critical.

Westjet and Turkish incidents are irrelevant. Westjet malfunctioned, pilot took control and landed safely - that's what pilots are there for. Turkish airplane also malfunctioned and gave multiple warnings over several minutes, but pilots didn't pay attention to what the aircraft was doing until stall warning activated at 460 feet, by which time it was too late. Had they paid attention, they would've also recovered and landed safely.

In contrast, Airbuses systems didn't malfunction. They worked as designed and made the already difficult situation (landing in bad weather) deadly due to not responding like a pilot would expect. The design was deeply flawed, just like MCAS.

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 malfunctioned and gave multiple warnings over several minutes, but pilots didn't pay attention to what the aircraft was doing until stall warning activated at 460 feet, by which time it was too late. Had they paid attention, they would've also recovered and landed safely.

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

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.

And, that as far as we know, hasn't caused

I like thinking about this in a sort of hypothetical Sparta. Sparta had two kings from two different royal lines.

Suppose you're one of two kings, and the other royal line experiences some sort of dynastic hiccup. This inevitably happens to everyone.

A popular strategy throughout history is to capitalize on that hiccup by exterminating the existing royal line, or at least driving them out of power so you can take it yourself. As a king, you are ideally positioned to do this. Maybe you can take both thrones and be the double-king. Maybe you can put your cousin on the second throne. Maybe you can put a flunky on the second throne. Maybe you can get rid of the second throne, leaving yourself as sole king.

But once you do that, a precedent has been set. Your line will eventually stumble too, and it is likely to suffer whatever fate befell the other line the first time. Another strategy you have, back when the rival line first shows weakness, is to stake everything you have on your commitment to upholding the Spartan way of life as expressed in the dual kingship. Give rousing speeches on how unthinkable it would be for anything about the current setup to change. Throw all your considerable resources into supporting the king on the other throne, no matter how weak his position might look.

If that sticks, the other line is likely to remember that you were there when they needed you. But even more than that, you've just established that the dual kingship, and the two families who fill it, are an integral part of the culture, never to be questioned. That tradition may ultimately prove more helpful to you than any personal support. And it has such obvious benefits to the other royal line that, going forward, they will likely support it just as strongly as you do.

On this analogy, the problem with disturbing the Airbus / Boeing duopoly isn't that Boeing might start to compete with Airbus, provoking an arms race. The bigger problem is that (as you mention) some other company might start thinking they can make airplanes too, and who knows what could happen then.

Personally, I'd like to see Mitsubishi get back into the passenger plane business. They're already starting, but with a smaller regional jet.

https://en.wikipedia.org/wiki/Embraer_E-Jet_E2_family#E195-E...

https://en.wikipedia.org/wiki/Airbus_A220#/media/File:CSerie...

I think what's missing in the Airbus-Boeing debate is an appreciation for the role of engine manufacturers. The A220, E195-E2, and Mitsubishi SpaceJet are all built around P&W's new geared turbofan engines.

It seems to me that at this point in the evolution of the industry everybody effectively builds their planes around the capabilities and limits of available engine technology. The immediate cause of death of the A380 was the refusal of any engine manufacturer to design and sell a more modern engine. The A380 became inefficient because its engines were at least 1.5 generations behind, not because there were 4 of them. (Of course, the reason nobody wanted to invest in a newer engine was because the market was too small to make it worth their time, especially considering their struggles with existing commitments.)

I imagine any aerospace engineering company could design a state-of-the-art and competitive body around the available engines. Aircraft manufacturers seem to self-select into market niches not because of engineering costs and difficulties, but simply because the global markets aren't large enough to support a third wide body manufacturer and only barely large enough, if at all, to support another 737/A320.

Embraer's commercial business is owned by Boeing now — the subsidiary is called BBC.

https://www.reuters.com/article/us-boeing-airplane-southwest...

https://www.bizjournals.com/dallas/news/2019/07/29/southwest...

That's especially incredible considering Southwest pilots' union says in a lawsuit that the 737 MAX is unsafe.

https://www.seattletimes.com/business/boeing-aerospace/in-sc...

Well, in this case I'd argue that it was totally Boeing's responsibility to communicate to such customers that they couldn't do it.

Instead they nodded their heads, demanded the impossible from their engineers, demoted or fired people that questioned it and in the end offered a hacked solution, which killed over 300 people.

I don't think that your argument excuses their culpability in any way, shape or form.

If I offer you $1 million to shoot someone, and you go do that, two crimes have been committed. Pointing out that I'm also culpable in no way excuses your culpability. I would be the real source of the crime, as the instigator, having set out a strong incentive to commit the crime against your otherwise better judgement.

[0] http://news.aa.com/news/news-details/2011/AMR-Corporation-An...

The 737 MAX fiasco threatens this arrangement.

Because that's what manufacturers always did? If you only do iterative changes then eventually you run into a wall. Boeing engineers also knew that. The disagreement between what engineers wanted and what management wanted has been a point of contention for many years.

That was what Boeing and Airbus supposed to do: Sell the a320Neo and 737MAX for as long as possible and stay away from the wall. Now that Boeing screwed up, they may be forced to jump the wall and Airbus will have to follow. On the other side of the wall, they will sell the same number of planes.

While unchanged, the wing has seen a steady loading increase: to 83t on the first A321, then 89t and 93.5t, and is finally expected to go up to 101t on the A321XLR. This increased wing loading has meant higher take-off speeds, reaching close to the maximum tire speed limits, and a lower safety margin at altitude – in other words, a tighter “coffin corner”, and lower stability protection.

Airbus just hasn't had it's day yet.

If the company doesn't suffer for such failures then competition doesn't matter.

https://www.telegraph.co.uk/finance/2923861/Airbus-whistlebl...

Haha.. oh...

(FWIW, I think the A380 has superb pax comfort.)

I'm pretty sure we dropped about 500 feet straight down, but all I remember was being amazed how my cup of pepsi stayed on my tray and didn't fall over.

As for favorite plane, the lower pressurization and higher humidity of a 787 makes all the difference.

You need to plan ahead.

Sure, it was a handful for the manufacturer, luckily pulled it off, kinda broke even after some time. But it will be long gone when it will be really needed, when large hubs become even more congested or certain P2P lines heavily overgrow on themselves.

Even with the engine handicap the A380 was still generally competitive if fully loaded. And if not fully loaded it could still be competitive, as described by a recent story about the outsized role of the Dallas-Sydney route to Quantas' bottom line: https://simpleflying.com/dallas-sydney-qantas/ (see also https://www.dallasnews.com/business/airlines/2019/10/28/this...)

Considering that engine efficiency is perhaps the biggest contributor to financial viability, that says something very positive about the A380 approach and design. But as engines continued to advance the A380 would have lost even that edge.

Just to make things clear since I also work in the field.

Non conforming parts are not a problem, at least not from a safety perspective. It just means that the part is damaged (ex: scratched) or not up to specs, and that some analysis is required. A typical result is that the part is usable but with more frequent inspections and a reduced service life. It is more of a problem for the company because they are losing money fixing stuff instead of doing it right the first time.

Not knowing where each part is, conforming or not, is a really big problem, as mentioned by other posters.

We were all like, WTF. Photos were taken and sent; I really hope someone got fired.

This also led us to taking the aircraft completely apart and checking every nook and cranny. Found FOD and such in random places.

As a vet, this frustrates the hell out of me. We are trained to look out for one another and, especially in the case of aircraft maintenance, we are trained to police ourselves and each other.

Yes, we also had strict guidance and checklists, and we followed them (sometimes only as best as we could depending on the situation, like combat zones, lack of supplies, etc). But, paramount above all that was safety and making sure whatever we did impacted safety in a positive way.

Going into the civilian world, it frustrates the hell out of me how lazy everyone could be with things that could literally kill somebody if maintained incorrectly.

And honestly it really surprises me a little how much of this about Boeing is coming out into the lime light. I thought their standards would be higher.