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