Ethiopian 737 Max 8 crash and Fallout

[coriander]

Should not you have done the same extensive examination, before purchasing a car.

I agree, but the consequences of my car "failing to proceed" (in the words of Rolls Royce) are generally much less disastrous than an aircraft at 30,000 feet.

 

[jb747]

And it continues

Southwest extends B737 Max cancellations into 2020 – Business Traveller

The carrier said that the move would reduce last-minute flight cancellations and unexpected disruptions to customers’ travel plans…

www.businesstraveller.com

My sympathy for Southwest is zero. Of all the airlines, they are the most culpable with regard to the 737’s lack of timely and reasonable development.

I agree, but the consequences of my car "failing to proceed" (in the words of Rolls Royce) are generally much less disastrous than an aircraft at 30,000 feet.

Yes, but at what point do you decide that it is relevant. One life. A child’s life. My request is reasonable. I’m only asking you to spend a few man decades gaining the knowledge, and then studying every aspect. The man centuries necessary for such study of new aircraft is pretty much a linear scaling of that.

Ok, I think it’s a stupid idea.

Beyond that though, problems at 30,000’ are generally less of an issue than problems at 3,000’. In almost every aircraft accident, the biggest issue is time. Altitude (and fuel) buy time.

 

[MEL_Traveller]

Well, if the FAA (and CASA, and CAA, etc) don't actually have the resources, personnel, or knowledge to independently check every aspect of a new aircraft, how do you expect every individual airline to do so. How much knowledge of the manufacture of the gudgeon pins in your car do you have? Should not you have done the same extensive examination, before purchasing a car. Of course, if you'd be happy to still be flying in aircraft that can be understood by customers at that level, then that's all well and good, but biplanes were a bit slow and breezy.

I don't think this is necessarily a black and white situation. If we accept Lion Air may not have known about MCAS, once that accident happened, is it reasonable to put other airlines on notice? Or once an accident has happened, do we allow other airlines to continue to fly under the FAA/CASA/CAA certification without further questioning?

Depending on the circumstances, somewhere in the middle might be the right answer. At the very least I think operators should turn their minds to considering the issues.

 

[coriander]

Beyond that though, problems at 30,000’ are generally less of an issue than problems at 3,000’. In almost every aircraft accident, the biggest issue is time. Altitude (and fuel) buy time.

Smiling (as I demonstrate my lack of understanding)
Which is why I spey cats and you fly (flew) planes !

 

[jb747]

I don't think this is necessarily a black and white situation. If we accept Lion Air may not have known about MCAS, once that accident happened, is it reasonable to put other airlines on notice? Or once an accident has happened, do we allow other airlines to continue to fly under the FAA/CASA/CAA certification without further questioning?

Depending on the circumstances, somewhere in the middle might be the right answer. At the very least I think operators should turn their minds to considering the issues.

You're making the assumption that they weren't.

Boeing never gave out source code for MCAS (or anything else). Everyone, from the FAA and other regulators, through to all end users, was stuck with whatever information Boeing wanted to give out. Based on that information, MCAS was probably relatively benign compared to what we now understand. Of course, we also now know that Boeing's understanding of MCAS was also deeply flawed. My initial understanding was that the runaway trim procedure would stop it quickly. Even the Boeing CEO stated that, as he attempted to blame the crews. Now we know that not only is the entire activation sequence to MCAS flawed, but so is the way it operates. And then to cap that all off, the manual trim does not have the authority to re-trim the aircraft at any speed (and that calls into question the certification of the NG, and is why I've been so anti 'grandfathering').

As you look beyond Boeing, you'll then hit the FAA certification requirements. MCAS has been described as an anti stall measure, and it may act as one, but that's not the reason it was originally installed. The issue was that the amount of stick force (i.e. on the controls) to increase the angle of attack was not the same as the earlier 737s, and it reduced to quite low force at higher angles of attack. Basically, it meant that as you increased the angle of attack, it actually became ever easier to do so. Is that really such a terrible thing? Well, it is if you're trying to keep the same pilot certification for the new aircraft as you have for the older models. It's not a particularly desirable trait in an airliner anyway, but the same issue exists in plenty of military aircraft (the Macchi 326 that the RAAF used for instance). An anti stall device? Well, I've flown aircraft that pretty much can't be stalled (the A380), and others than can be (everything else). I don't greatly care either way. It certainly isn't something that you should sell your soul for. If the MAX had been designed with the knowledge that the pilots would be on a separate certification, then would these issues have arisen at all?

Nobody gives out source code, and then pretty well nobody has the ability to read it anyway. How many millions of lines of code would exist in an FBW aircraft?

 

[MEL_Traveller]

You're making the assumption that they weren't.

You mean put on notice? Maybe they were, and perhaps the investigation into the ET accident will give us more details... but is putting a copilot of just 200 hours experience on an aircraft suspected to have MCAS issues a response to being 'on notice'? I wonder if the airline industry, including regulators, is sufficiently at arms length to assess the risks?

 

[jb747]

You mean put on notice? Maybe they were, and perhaps the investigation into the ET accident will give us more details... but is putting a copilot of just 200 hours experience on an aircraft suspected to have MCAS issues a response to being 'on notice'? I wonder if the airline industry, including regulators, is sufficiently at arms length to assess the risks?

Well, let's work this the other way. I don't think 200 hour (actually about 380 hour) pilots should be in any airliner. Sadly, that's not the world we live in. But, from all accounts, said FO performed quite well, so perhaps he should be left out of the discussion. Basically though, if we are accepting cadet pilots with so few hours, then his placement in a MAX is immaterial. Actually, he would probably be much more at home in it, than an earlier version of the 737.

The issue is actually much simpler. Was the aircraft flyable, by anyone, in the scenario they had? From what I've read so far, it would seem that the answer is no. So, no matter who your pilot was, it would not have mattered. This is an aircraft that should not have been certified at all. BUT, that's not something that was known by airlines or pilots beforehand. We think (!) we know that now, but I'm sure there is yet more to the story.

 

[stm1sydney]

Was the aircraft flyable, by anyone, in the scenario they had? From what I've read so far, it would seem that the answer is no.

Could they not have flown the aircraft by engaging the STAB TRIM CUTOUT switches at the earliest opportunity (and left them at CUTOUT)?

 

[jb747]

Could they not have flown the aircraft by engaging the STAB TRIM CUTOUT switches at the earliest opportunity (and left them at CUTOUT)?

You aren’t the CEO of Boeing by any chance, are you? That was his argument initially too.

The answer is that there was a window of a few seconds in which it could be done. But it was not reasonable to expect any pilots, other than ones who were prewarned that it was happening (i.e. the Boeing test pilots) to know what was happening in that time frame. The overwhelming power of the rate that Boeing had given to MCAS, meant that even if you were able to trim against it, you were in about a 5 to 1 battle (its rate vs yours). The aircraft will pitch down, and need even more trim, if you reduce the power.

Added to that, even though in many ways it’s a runaway trim (and that was my thought initially), the standard initial response to runway trim was actually deactivated by Boeing (and also not promulgated). So, by the time you’d worked out that it wasn’t runaway trim, but MCAS (and when the second accident happened, Boeing still hadn’t released enough information to reliably do this), those 3-5 seconds would be long gone.

According to some news sources (!), the regulators actually walked out of the last meeting with Boeing, after they continued to obfuscate on a number of items. I really wonder if at least some of them aren’t getting close to demanding the aircraft be totally recertified....something that is probably not possible. Imagine making a 1965 car fulfil all of the modern vehicle requirements.

I guess one thing that you can be sure of, is that Boeing won’t be getting much in the way of leeway with the 777X.

 

[serfty]

after they continued to obfuscate on a number of items.

Its getting worse ... Former Boeing official subpoenaed in 737 MAX probe won’t turn over documents, citing Fifth Amendment protection

 

[oz_mark]

Not sure if has been reported here EASAs conditions on return to service:

1. Design changes proposed by Boeing are EASA approved (no delegation to FAA).
2. An "additional and broader independent design review" by EASA
3. The causes of the two fatal crashes were deemed to have been sufficiently understood; and
4. That flight crews have been adequately trained in any changes to the plane

European Aviation Safety Agency Says 'No Delegation' Of 737 MAX Approval To FAA

The FAA's actions were seen as an instance of "regulatory capture" by Boeing, and the EASA now says it will not delegate to U.S. regulator the 737 MAX approval process.

www.ibtimes.com

 

[Moody]

Should Boeing and Airbus be forced to install a Big Red Button that the PF can press while loudly exclaiming "Give me the fecking plane!"?

 

[jb747]

Should Boeing and Airbus be forced to install a Big Red Button that the PF can press while loudly exclaiming "Give me the fecking plane!"?

In an FBW aircraft, all your big red button would do is force a law change. There could be an argument for that, but it can already be achieved fairly simply, and quickly, in the 380 (and I assume, other ABs).

The FBW Boeings, I don’t know, but expect they’d be broadly similar to the AB.

But, the issue doesn’t seem to be FBW per se. That’s actually a pretty robust technology these days. The problem is sneaky, partial, FBW, on aircraft that were never built for the technology. Boeing was outright saying that it knew better than the pilots, so not only would it install MCAS, but it would be impossible to reasonably get rid of. Oh, and we aren’t going to tell you about it either. Putting a time limit on grandfathering would probably have achieved all that the regulators needed. Allowing new aircraft to be built on top of systems that were developed and tested, in the early ‘60s, is the root problem behind all of this.

 

[Moody]

So giving the pilot FULL control of the aircraft wouldn't have saved them in either case?

 

[p--and--t]

Grandfathering - jb747's favourite word of late (seems to creep into most posts)

 

[Franky]

Grandfathering - jb747's favourite word of late (seems to creep into most posts)

True - but would seem to be very apt....

 

[oz_mark]

SilkAirs fleet of 737MAX aircraft are said to be being moved to storage in Alice Springs. The Singapore climate doesn't lend itself to long term storage of aircraft.

 

[jb747]

So giving the pilot FULL control of the aircraft wouldn't have saved them in either case?

In an aircraft with FBW, in normal law, when you move the control stick you are asking for a result. You move it left, you want the aircraft to roll left at a certain rate. You don’t actually care what control surface is moved, or by how much. At various times, ailerons, spoilers, and rudder can be involved to give that result. That’s all left to the FBW computers This law also comes with various protections. In particular it has stall protection, that will allow you to pull full aft stick, with the aircraft limiting itself to the point of maximum angle of attack. So, not only are you protected from inadvertent stall, but it also allows you to extract the maximum aerodynamic performance if you happen to need it (i.e. in a wind shear or terrain encounter).

In direct law, the control column no longer asks for a set result, but simply proportionally applies the control surfaces...exactly as non FBW aircraft have always done. You have full control, but that also means that there are no longer any protections. AF447 was in a subset of this mode.

But, the 737 is not an FBW aircraft. In it motion of the controls relates directly to motion of the control surfaces. Always. So, it doesn’t have ‘laws’, and is actually in the mode that FBW aircraft revert to after failures.

The problem is that Boeing superimposed another system on top of the normal 737 flight controls, and then didn’t tell anyone about it. Yes, MCAS runaway superficially looks like a runaway trim, and yes, the procedure to deal with it is the same, once you get to the checklist. But, in Boeings, for time immemorial, the procedure to control runaway trim has started with you applying control pressure in the opposite direction to the runaway. That’s a natural reaction, and there were switches hidden in the control column that sensed this opposition, and which stopped the trim. That meant that by the time you actually went to the checklist, and then shut off the trim power, it would not have been able to move far from its desired position. But, Boeing deactivated these switches for MCAS activation, and again didn’t tell anyone. In so doing they effectively used up the time that pilots would have had get on top of the issue.

The upshot is that by the time the trim power is cut off, there’s a good chance that the MCAS has had the chance to wind in all, or nearly all, of the nose down trim. That is a very large amount of nose down force, and is way beyond the amount of nose up force that can be applied via the elevators. The only way to trim at that point is via the trim wheel, which we’re told is slow, and on which the loadings are potentially so high that it can’t actually be moved. Every other major aircraft has backup ELECTRIC trim. So we’re back to grandfathering.

 

[flydoc]

SilkAirs fleet of 737MAX aircraft are said to be being moved to storage in Alice Springs. The Singapore climate doesn't lend itself to long term storage of aircraft.

Flight parameters said to be below 20,000 feet with 1st stage flap deployed to disarm the MCAS system

Silk Air to relocate B737 MAX fleet to Alice Springs - PPRuNe Forums

Australia, New Zealand & the Pacific - Silk Air to relocate B737 MAX fleet to Alice Springs - CASA Australia has given approval for the Silk Air fleet of Boeing 737 MAX to be relocated to dry storage in Alice Springs. The aircraft are to be flown below 20,000 feet with 1st stage flap deployed to...

www.pprune.org

 

[serfty]

What really brought down the Boeing 737 Max? — The New York Times

Malfunctions caused two deadly crashes. But an industry that puts unprepared pilots in the coughpit is just as guilty.

apple.news

What Really Brought Down the Boeing 737 Max? (Published 2019)

Malfunctions caused two deadly crashes. But an industry that puts unprepared pilots in the coughpit is just as guilty.

www.nytimes.com

A very interesting article. 2 links to the same article.

I found that whenever he would write something critical about Boeing he would quickly take it back or divert the attention away from their failures. I had developed a conspiracy theory of what I thought Lion Air’s “best practice” is and it’s about as bad as I perceived it to be and probably worse.

You could guess where the article was heading before halfway.

Yes, the way the pilots reacted and ground crew handled thing contributed to the "holes lining up in the swiss cheese", but one of the first couple of holes was caused by MCAS.

Indeed, without MCAS, this thread would not exist.