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Plane Tests Must Use Average Pilots, NTSB Says After 737 Max Crashes

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Re: Plane Tests Must Use Average Pilots, NTSB Says After 737 Max Crashes

#211

Post by OrgNet »

inimino wrote: post #204
OrgNet wrote: post #191

Earlier quoted context omitted.

well, at least they could try. but yeah I know that most software sucks and can't be predicted 100%

They do try. Avionics is miles ahead of everyday commercial stuff like your desktop computer in reliability and correctness. This is not just about software, a plane is a complex physical system and the idea of absolute control is a fantasy. This is why you need alternatives, failsafes, contingency plans, and training in dealing with unexpected failure modes.

> Avionics is miles ahead of everyday commercial stuff like your desktop computer in reliability and correctness.

What OS that they use that is so much better?

Re: Plane Tests Must Use Average Pilots, NTSB Says After 737 Max Crashes

#212

Post by [deleted] »

dahart wrote: post #99
treis wrote: post #84

Earlier quoted context omitted.

>Though I can’t help but wonder if this is a very subtle re-framing of the Max accidents to shift blame back towards pilots. Blame is a loaded word. Boeing assumed that pilots could be relied upon to recover from a MCAS induced runaway trim. Practice has shown that they can't. Whether Boeing or the pilots is at fault is, from a safety perspective, irrelevant. The bottom line is that an assumption was made, it was wro…

I appreciate the attempt to be diplomatic, and I agree that using average pilots is sensible. But, with respect, I could not disagree more with the rest of that. > Blame is a loaded word. Boeing’s response to the accidents was to blame the pilots, there is precedent for this word in this situation. https://www.cnn.com/2019/05/23/business/american-airlines-bo... > Boeing assumed that pilots could be relied upon No, Bo…

[deleted]

Re: Plane Tests Must Use Average Pilots, NTSB Says After 737 Max Crashes

#213

Post by not_a_cop75 »

oliveshell wrote: post #74
not_a_cop75 wrote: post #70

What about below average pilots? If half of them are still going to crash, shouldn't the true idiots in the industry be the test dummies? No pun intended.

Fortunately, true idiots don’t get licensed as airline transport pilots.

True, but that doesn't mean there aren't "true idiots in the industry". Thankfully, most commuter planes drive like buses and don't have the excitement to draw idiocy like extreme sports does.

Re: Plane Tests Must Use Average Pilots, NTSB Says After 737 Max Crashes

#214

Post by cmurf »

o-__-o wrote: post #154
treis wrote: post #142

Earlier quoted context omitted.

>Boeing’s response to the accidents was to blame the pilots, there is precedent for this word in this situation. Your cite says Boeing said: >The actions of the pilots played a role in the chain of events that caused the crashes Which isn't blaming them and is factually correct in both crashes. The Lion Air pilots didn't disable electric trim and the Ethiopian air ones turned it back on. Those actions played a role i…

Don’t forget the pilot of the previous LA607 flight was able to recover successfully. Other pilot crew had more flight time, thus more experience. Look at NTSB crash data, experienced crews have a higher chance of lower fatalities in an accident. Why? Because these pilots understand their vehicle like the back of their hand. A 5000+ hour pilot has deep knowledge, for instance, of the hydraulic system of the plane and…

The pilot of LNI043 did NOT recover successfully. He failed, the first officer failed. It was a jump pilot who recognized the issue and the solution. Also the MCAS upset in LNI043 was no where near as aggressive as LNI610 or ET302.

Literally no one disputes the importance of experience. But you keep throwing it out as relevant to LNI610 and ET302 without any explanation or causal connection. In the case of Colgan Air 3407, the two pilots had 5500+ hours of experience between them, each well over the current ATP experience of 1500 hours total time requirement, and yet the captain inexplicably, likely due to startle factor, pulled back on the yoke contrary to his training, and made the stall worse and the airplane unrecoverable. Who cares if 5000+ hour pilots know to drop flaps in an emergency if they get startled in a stall and make the stall worse by pulling back on the yoke!

Re: Plane Tests Must Use Average Pilots, NTSB Says After 737 Max Crashes

#215

Post by sterileopinions »

treis wrote: post #84
dahart wrote: post #62

This seems like a good thing, they should be testing with people who don’t know the answers. Though I can’t help but wonder if this is a very subtle re-framing of the Max accidents to shift blame back towards pilots. This approach of a regulatory agency recommending “average pilot” testing makes both the agency and Boeing look good, and tends to downplay the fact that Boeing intentionally avoided training the pilots,…

>Though I can’t help but wonder if this is a very subtle re-framing of the Max accidents to shift blame back towards pilots. Blame is a loaded word. Boeing assumed that pilots could be relied upon to recover from a MCAS induced runaway trim. Practice has shown that they can't. Whether Boeing or the pilots is at fault is, from a safety perspective, irrelevant. The bottom line is that an assumption was made, it was wro…

>Whether Boeing or the pilots is at fault is, from a safety perspective, irrelevant.

It's quite literally the most relevant talking point in this entire conversation.

Re: Plane Tests Must Use Average Pilots, NTSB Says After 737 Max Crashes

#216

Post by mlindner »

kayfox wrote: post #132
JanSt wrote: post #106

Earlier quoted context omitted.

My understanding is that the pilots had only about 40 seconds time to solve the problem and were trained for one hour with an iPad (not on the MCAS, but the whole 737 Max). I'm not sure whether this is a question of pilots' standards in the US vs around the world.

The general idea was that pilots would correctly recognize large amounts of undesired and uncommanded trim being runaway trim and perform the checklist to resolve that issue that they are expected to know by memory, since there is a need to execute it fast, without paging through the Quick Reference Handbook. This is not a checklist that was introduced with the 737 MAX, but one that has existed since the introduction…

I just want to say thank you for you great replies throughout this thread. There is too much simplification of this incident everywhere in the media, and even in technical circles to "Boeing put out a horrible design because of cost cutting that killed people". These are things I've tried to explain, but you put it much more eloquently.

Re: Plane Tests Must Use Average Pilots, NTSB Says After 737 Max Crashes

#217

Post by cmurf »

mlyle wrote: post #193
dahart wrote: post #99

Earlier quoted context omitted.

I appreciate the attempt to be diplomatic, and I agree that using average pilots is sensible. But, with respect, I could not disagree more with the rest of that. > Blame is a loaded word. Boeing’s response to the accidents was to blame the pilots, there is precedent for this word in this situation. https://www.cnn.com/2019/05/23/business/american-airlines-bo... > Boeing assumed that pilots could be relied upon No, Bo…

In aviation we tend to look at failure chains . There are many, many things that went wrong: 1. The stuck AOA instrumentation on the plane. 2. MCAS not using redundant AOA information and being fooled by the stuck instrumentation. 3. Lack of clear indication of what MCAS was doing contributing to flight crew confusion. 4. Improper execution of the runaway trim procedure/checklist by flight crew. 5. Training shortcomi…

What was improper about the execution of runaway trim by either LNI610 or ET302? Those two cases are different. LNI043 and LNI610 are also different but the similarity is 4 of 5 pilots didn't recognize it as runaway trim. And does it? Boeing says it does, but saying things doesn't make it true. It's much more aggressive than the kind of runaway trim pilots are trained for.

So again, what was improper? Especially ET302 where they absolutely did run the checklist rather immediately and by that time it was already in a mistrim situation.

Re: Plane Tests Must Use Average Pilots, NTSB Says After 737 Max Crashes

#218

Post by anigbrowl »

chrisseaton wrote: post #61
kalenx wrote: post #54

Earlier quoted context omitted.

Average does not have the same meaning in the context of this link and yours. We are not talking about physical measurements here.

Why doesn’t the same principle apply? One pilot is very good at one skill, another very good at some other skill. There exists no mean pilot that is fairly good at both, so designing or testing for that is a bad idea. Replace body dimensions with skill sets and it’s the same issue.

You understand a Venn diagram just fine though. It's the same sort of problem, just generalize to n dimensions and use a clustering algorithm, or decompose an overly complex problem into multiple clusters.

Re: Plane Tests Must Use Average Pilots, NTSB Says After 737 Max Crashes

#219

Post by heisenbit »

mlyle wrote: post #193
dahart wrote: post #99

Earlier quoted context omitted.

I appreciate the attempt to be diplomatic, and I agree that using average pilots is sensible. But, with respect, I could not disagree more with the rest of that. > Blame is a loaded word. Boeing’s response to the accidents was to blame the pilots, there is precedent for this word in this situation. https://www.cnn.com/2019/05/23/business/american-airlines-bo... > Boeing assumed that pilots could be relied upon No, Bo…

In aviation we tend to look at failure chains . There are many, many things that went wrong: 1. The stuck AOA instrumentation on the plane. 2. MCAS not using redundant AOA information and being fooled by the stuck instrumentation. 3. Lack of clear indication of what MCAS was doing contributing to flight crew confusion. 4. Improper execution of the runaway trim procedure/checklist by flight crew. 5. Training shortcomi…

Nope, the excessive authority given to MCAS in combination with the hard to rewind trim (particularly at high speeds) were a mousetrap to be sprung. There are many ways to trigger this mousetrap. This is not a chain, this is a cluster with many chains hanging from it.

Re: Plane Tests Must Use Average Pilots, NTSB Says After 737 Max Crashes

#220

Post by crooked-v »

I'm immediately reminded of the whole thing with Captain Sully, where initial recreations in simulators could safely land the plane on the ground... but only because the pilots already knew exactly what to do, instead of having any realistic delays to evaluate the state of the plane and consider landing options.
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