The driving force behind the Max design band-aids is the fact that airline management want to limit the amount of training required. And as need to know information tends to be the only bits that filter through a lot of background info is lost to new generations of pilots. The trim runaway scenario has some consequences that are no longer mentioned in the ‘books’ - the simple memory items required to correct a runaway are not necessarily simple to execute. If within Boeing there was a lack of information sharing, how on earth would anyone expect the pilots driving it to then have the full picture? Some ‘old-school’ pilots might still recollect handling issues, but my experience is that many ‘new-school’ pilots will not have realized some of the fall-out.
The 737-Max is probably the most carefully and thoroughly sorted out airplane going right now. The training now required might well be the same. Who knows what defects and potential disasters are out there in the rest of the fleet?
Yes. The crew that flew the Lion Air 610 accident airplane the day before was presented with the same runaway, and they handled it.
I may be old (73) but I am becoming increasingly unsure as to the continual reliance on software to solve basic flying skills. Am I the only retired Boeing captain who remembers being taught during the 707 ground school, that the best way to stop a runaway stab was either to grab the co-pilot’s thigh and clamp it to the right hand stab trim wheel until his trousers caught fire (almost a joke - but it worked!), or alternatively hit the stab and mach trim cut-out switches off, and as a final fix, shout out “SAM255” and find the circuit breakers for the Stabiliser, Autopilot and Mach Trim on the P Panels 2,5 and 5. Essentially the same thing worked for the 727 and 737s. The breakers had white or yellow outlines to make them easy to find. Strange to tell, that for a very swept wing and moderately unstable beast like the 707, it did not have any Angle of Attack indication for the crew and most of us were taught recovery from unusual attitudes should still revolve around “needle, ball & airspeed” with a good look at one of three horizons to determine which was the odd one out. Or I am just old?
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I don’t quite understand the fascination with a three-AOA concept. The questioner seems to imply that the computers need to know which AOA signal is correct. They don’t. They only need to know that one of them is wrong, which means that the MCAS routine should not be employed.
Still, Boeing went a step further with an internal algorithm that functions as part of the comparator. To me, this is the very synthetic value that the questioners are asking for. And still it is not used to determine which one is wrong. Just that one of them is wrong, and MCAS should not be activated.
Calling the 737-MAX “flawed” is an understatement, and a semantic dodge. The gap between a “flawed”
and an “unsafe” aircraft is a distinction without a difference. Likewise, what an American crew might do
in an emergency is irrelevant, unless no one else is allowed to fly them. Should no one outside the U.S.
drive a Ford, or use a Black & Decker power tool? Moreover, if that all-American crew must compensate
for design errors and intrinsic defects, or must expect the worst to happen at any moment, then the only
ones on board should be test pilots, astronauts, and flying aces with a death wish. Even if the 737-MAX
is safe, what about the rest of Boeing’s fleet? After Ralph Nader wrote “Unsafe at Any Speed” (1965) it
became customary to praise GM for “fixing” the Corvair, as if that meant there was nothing wrong with
any of their other vehicles, or that the Corvair was merely an anomaly. Giving Boeing the benefit of the
doubt merely encourages them to return to business as usual, as if nothing had happened, or at least
nothing so serious as to require either a complete overhaul of their manufacturing process or else the
indefinite suspension of their operations, in the interest of public safety and of upholding standards of aircraft construction and maintenance. A quick fix is worse than none at all. While I share the hope
for better weather in 2021, it won’t happen without greater diligence and vigilance in all walks of life.
I agree with you. Job One is fly the damned airplane! Bells, horns, stick-shakers are warnings of impending problems or sometimes not. In this case, Boeing’s errors challenged the pilots, but it was the failure of the crew that caused the loss of life.
I’m typed in the 727, 737, 757 and 767 and instructed in the 737 as well as served as test pilot for AC coming out of maintenance. I instructed ATP’s for several years and also flew the line. No pilot that I instructed or checked would ever have failed to have disconnected the stab trim OR failed to fly the airplane.
And as an aside, can I point out that a triple autopilot, no-pilot AC would have come to the same end as the failed crews did. GIGO.
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Wow!
I concur with Dennis R on this one.
I am insulted when commentators have the gumption to say this Max accident would never happen to an American pilot. That is out and out racist
Remember corporations are first responsible to their shareholders not their workers or spending on safety. It’s how much can we get away with from squeezing workers and incompetence of regulators.
“But two of the three developing-world crews who were tested failed. Recall that the day before Lion Air 610 plunged into the Java Sea in October 2018, pilots who had flown the same airplane the day before encountered the same abnormal and, thanks in part to a knowledgeable jump seater, resolved it. They reported the malfunction and maintenance techs failed to diagnose it correctly and thus failed to fix it, setting up the accident scenario.”
As I remember, the Lion Air Maintenance crew removed the failed or suspect AOA with a replacement AOA that was overhauled incorrectly by an American, FL based company. A bad AOA was replaced by a certified but equally bad AOA. It would be interesting to find out who might have built or overhauled the first failed Lion Air AOA as well as who might have built or overhauled the AOA installed on the Ethiopian MAX. I would hope the 400 grounded Max’s have those AOA manufacturers checked as well. To me, how do you fail to diagnose a system you don’t know is there?
As pointed out, the MCAS response with intermittent not a trim runaway that defines itself by getting worse in a very progressive but predictable way. Maybe it has happened, but I am not aware of a runaway trim system going full nose up then reversing itself going full nose down. Nor have a ever heard of a trim system being intermittent one way but responding to pilot inputs going the opposite way, yet going the other direction again or stopping depending on flap position, airspeed, or attitude. Once again, I can hear the choir singing, “if I were there, I would…”. But none of us were there in either crash aircraft. Plus, as the blog points out, no one in either maintenance nor the crash crew knew there was a thing called MCAS on board. For that matter, until the crashes, no MAX buyers knew it was on board.
Would I fly on MAX today? NO. Maybe sometime in the future after a few thousand more souls have already been used as paying guinea pigs including American pilots.
I can hear Bullwinkle asking Rocky “wanna see me pull a rabbit outta my hat?” After which Rocky says “Again?” Followed with Bullwinkle’s confident reply, “this time fer sure!” Boeing seems to be the new Bullwinkle saying this time fer sure.
Besides, Covid-19 needs requires the US to pull another rabbit out of its hat. I would like to know a verifiable solution to Covid before getting on any airliner. So far, all I am hearing is…this time fer sure. MAX is the least of my worries.
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Let me add a little detail. The Lion Air 610 accident aircraft had its left AoA replaced on October 28 with a unit that was improperly overhauled by a company in Miami. The next day, it flew with that AoA and the crew that managed to recover from the MCAS misfire reported what they saw: IAS disagree. They couldn’t report AoA disagree because the aircraft didn’t have that capability.
The maintainers in Jakarta examined the IAS disagree fault and flushed both pitot systems. They didn’t touch or diagnose the faulty AoA because they had no reason to suspect it was faulty. And they didn’t know about MCAS or if they did, they didn’t connect the dots. I’m not sure anyone would have.
Have not seen it here yet, but I am sure it will come – the fact that some of the pilots on the crashed aircraft and elsewhere in the system “only had 350 hours”.
Yeah well think about it – that meant they were flying every day for a hour for a year. (Plus doing all the ground exams – with ATP boasts are Master Science level.
If you need longer than that to fly your areoplane there is a lot wrong with it.
I won’t go!
“…as an aside, can I point out that a triple autopilot, no-pilot AC would have come to the same end as the failed crews did. GIGO.”
Point and click. But you’re wrong.
The infamous MCAS is inoperative when the aircraft is being flown by the autopilot. MCAS exists to COMPLY with an existing certification REQUIREMENT for linearity of control forces presented to HUMAN PILOTS.
Be careful what you ask for.
“The gap between a ‘flawed’
and an ‘unsafe’ aircraft is a distinction without a difference.”
Really? So an aircraft with an out-of-service lavatory (clearly a flaw) is an “unsafe aircraft?”
By your reasoning, no aircraft can be safe, because - since nothing is perfect - all aircraft include flaws.
Perhaps your cited distinction actually includes differences.
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“If you need longer than that to fly your areoplane there is a lot wrong with it.”
Or just maybe, there’s a lot wrong with the pilot.
YARS, keeping “flawed” in 737 MAX context is sound. I think.
I think that there are cultural differences in how people will approach machinery. If you come from a culture which understands that mechanical devices will kill without warning because of an underlying problem then you will understand it is your job to stop the disaster before it can go further. If you assume the machine knows better the operator you won’t be able to stop it before the situation gets out of control. Airline pilots who fly and understand the systems logic of their airplanes understand mechanical faults and how they will jump out at the worst time. The “SAM255” is an example. The Air France 447 crash and the Tesla Harry Potter beheading are example of when the operator does not not understand his place in the chain of events.
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“There is no fork.”
The second “not” was a mistake. Sorry.
So Why Would You Fly A 737 MAX? Or Not. It’s an entirely different kind of flying… altogether.
Yeah, sure Dave, whatever you say…
The FAA has completely punted on the issue of whether it is legitimate to use a mere software patch to paper over a fundamental instability issue in a transport category aircraft.
To be sure, Boeing has been very careful to couch the existence of MCAS (when they were forced by circumstances to actually acknowlege its existence) as one of correcting the “feel” of the pitch axis in certain high AOA regimes of flight. “Feel” is merely a euphemism for instability, a word that Boeing shall not breathe.
The fact remains that if the lift of the much larger engine nacelles (forward of the CG) and higher thrust of the new engines causes the airplane to want to pitch up so badly (in high AOA and high thrust flight) that Boeing needed to add MCAS to crank in nose-down stabilizer trim, its is unstable. This violates a basic tenet of certification gospel: aircraft must be naturally stable throughout the flight envelope.
The FAA has, by their RTS approval, tacitly signaled that software patches for instability defects are now OK. I think this is dangerous. We need to have a full and thorogh debate about this question and not allow the FAA to sweep it under the carpet.
These software patch solutions might, in fact, be doable with modern technology but the issue needs to be thrashed out by healthy debate and design requirements stipulated so that the sort of sophomorically half-baked engineering errors Boeing demonstrated with the MCAS are not repeated.
In fact, the current “fix” for the MAX (now rebranded as the 737-8) ignores (among other things) the engineering principle of “critical triangles of agreement”; critical systems must have three inputs with a comparator routine to identify and disregard the outlier. As an example, modern jets have three pitot tubes, three Air Data Computers, three autopilots, etc. Boeing is still trying to do it on the cheap.
The FAA is allowing Boeing to get away with it.
I won’t ride on a MAX (-8).
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I followed the 737 MAX accidents closely, and I’ve flown in Indonesia.
I wish the racism card would not be played so often, either for or against the two accident crews, as it obscures the realities of foreign operators.
Indonesia is literally on the other side of the world, gets delayed information, and struggles to maintain enough aircraft parts. So they are at a disadvantage that should be recognized. The least manufacturers can do is to not guinea pig operators that already have their hands full.
The Indonesian NTSB determined that blame for their accident shared equal blame between the pilots, mechanics and Boeing.
Boeing put those pilots into situations where they became test pilots, with a couple hundred passengers in the back.