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Post by George Carty - HJG on Mar 19, 2019 8:59:50 GMT
Both of these aircraft have dangerous handling deficiencies resulting from attempts to make them more fuel-efficient than their predecessors (the 737NG and the DC-10 respectively) without requiring too many expensive design changes, and both attempted to use computers to compensate for these deficiencies.
With the MD-11 the issue was a too-small tailplane, while with the 737 Max the issue was that the engines were placed too far forward (because they were a higher bypass ratio – and therefore greater diameter – than the CFM56s of earlier 737 variants).
Thoughts?
George
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Post by Peter Liddell - HJG Admin on Mar 19, 2019 12:05:56 GMT
I've talked to 3 people who are part of the Air Canada max team. Their consensus is that there is more than a little suspicion of pilot training deficiencies more than design issues. If (as everyone is assuming and suggesting) MCAS is causing an uncommanded elevator trim down it's going to be a software fix and possibly making the additional AOA vane that Southwest ordered standard. And as they all said there are several ways of disabling MCAS. The bigger question is what is the fallout for the FAA and the certification process going to be, it seems like the FAA rubber stamping may have run a little too far.
I don't see the MD-11 as much as the A320 honestly.
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Post by Mike Monce - HJG on Mar 19, 2019 12:31:03 GMT
I had this conversation with the two ex Pan Am pilots here. Now, they have been retired for awhile so their opinions are obviously shaded by their experience. Both of them expressed the conviction of "too much darn computer", and attempts to take the pilot out of the equation. The younger of the two said that Boeing was caught trying to "out Airbus, Airbus". He said that Airbus, in order to sell to third world countries, made automation a high priority so not as much training was needed; while Boeing was always of the design philosophy that the pilot had the ultimate decision. Both were disappointed with Boeing as they both flew nothing but Boeings in the careers.
This all assumes we know exactly what happened, but the WSJ published an article last week that showed Boeing was already implementing a software fix on the basis of the Lion crash.
Mike
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Post by walterleo on Mar 19, 2019 14:34:39 GMT
Hi friends:
Maybe there is a similarity by overextending a tried design too much. BUT: The B 767-300 crash of LAUDA air comes to my mind LAUDA AIR 004 crashed due to a uncommanded opening of a reverser at full climb power at FL 270 at high Mach. Nobody at Boeing or FAA knew before that an opening reverser could crash an airliner, so mechanical locks where not applied and pilot training and the manuals did not regard that as a dangerous situation. To be just, the aircraft had since one year problems with the implied reverser, the service people could not cope with, but did not report the problems to Boeing and tried to solve it by sensless makeshift solutions in confidence, that the minimum equipment list did not name the reversers.
But this was not a computer programming problem but a flaw of the design and a testing method to fly with an opening reverser at 200 kts down low after take off and "extrapolating" the results over an entire flight. The FAA swallowed that!
The cocktail of the B 737 Max tragedy contains a good dose of undue rush to bring the new baby to the airlines, the FAA falling prey to the neoliberal philosphy of "outsourcing" vital testing and checking to the producers and Boeings greed to defend markets against AIRBUS.
Kind regards
Walter
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Post by christrott on Mar 20, 2019 14:59:50 GMT
I'm sorry, but this whole hullabaloo over MCAS is BS. Yes, Boeing made a mistake by not detailing its existence and operation, however we know that in the Lion Air crash, there were at least 2 prior occurrences of the MCAS activation due to the AOA vane issue (and the AOA issue was throwing warnings in the cockpit because of it) and both crews followed normal procedures for a runaway trim and activated the stabilizer cut-out switches. They then flew the plane normally to its destination without further issues. Recognizing that the trim is doing something uncommanded (by the crew) and then dealing with it is pretty basic. Period. The failure of training to ensure that they understand the basics of how to operate an airplane with "automation" that you can find on even fairly basic IFR-equipped Cessna 172s is where the problem is.
We've now had 4 accidents due to pilots not being able to just FLY THE PLANE.
Air France 447 - 2 relatively inexperienced crewmembers improperly respond to an iced-over pitot system. The issue of the pitot tubes icing over is a well known flaw with the A330/A340 series and Airbus had attempted to fix the problem several times without 100% success. The only way to fix it is a complete redesign of the pitot system.
Asiana 214 - 2 relatively experienced pilots, but both in inexperienced positions (Captain was trainee, "FO" was a captain recently promoted to instructor), failure to follow SOP, and over-reliance on automation resulted in the pilot attempting semi-automated operations inconsistent with training. Additionally, it was found in the investigation that Asiana actively discouraged hand-flying the aircraft resulting in pilots not being familiar with how to actually operate the aircraft in manual mode during normal operations.
Lion Air 610 - 2 relatively experienced pilots, but both new to the aircraft. Both their initial 737 and transition training handled by 3rd party (Airbus ironically) to European standards. Again - heavy reliance on automation in the training program, as is Airbus's design philosophy and how many European airlines want operations. Both crewmembers had relatively little "simple aircraft" operating experience, having both been former military pilots, so exposure to basic ideas of operation like electric trim cutout is unknown.
Ethiopian 302 - 1 fairly experienced pilot, but relatively new to the 737 and especially the 737MAX, and one pilot who had just graduated the Ethiopian Airlines academy with 200 hours TOTAL. Beyond this basically creating a single-pilot operation, in confict with Boeing's operating philosophy, it also handicapped the crew with any emergency because one pilot had NO real experience outside a training environment. The other pilot, while having been with the company for a decade, had less than 2 years with the 737, having moved from another airframe (I'm not sure it was made clear if he came from the DHC-8 or 777). We don't have a history on the airframe, but we do know that the pilot should have been equipped with the knowledge about MCAS now and that if it began to activate, he should have recognized it and then reacted.
However here's the problem - there's "similarities" except for the fact that this accident was "C"FIT - they flew into rising terrain while in essentially level flight and in excess of 350 knots. There is a 300 meter+ long scar in the side of the hill as the plane skidded and then dug into the ground leaving very little in the way of large debris. Lion Air dove into the ocean after aerodynamically stalling. While the impact was at ~250 knots, it wasn't because it was a power-dive, it was because of the stall. The ADS-B data can be ignored, it was poor quality due to low coverage. The radar data shows variations, but not nearly as wild as the ADS-B "interpolation" suggested. I'm still not 100% convinced that this was again an AoA sensor issue. If it was, simply slowing down and deploying the flaps or activating the autopilot would have removed MCAS from the equation. They didn't try either apparently, so one has to wonder if there was something else distracting them. Again, they should have been aware of MCAS and what it does now. They should have also known the errors that the Lion Air crews saw prior to and on the accident flight and known how to react. They didn't - so the issue is either training, experience, or something else. It's not the airplane.
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Post by christrott on Mar 20, 2019 15:06:32 GMT
Oh, and as to the "dangerous handling deficiencies" - this has been majorly overblown. MCAS exists because of an FAA-forced "edge case". The FAA requires that anything that has a 1-in-a-million or better chance of happening to have some sort of redundancy to address it. There was a slight chance that in some very edge case stall scenarios that a pilot might not react fast enough to begin bringing the nose down and the application of power would make the elevator insufficent to recover. MCAS was designed to assist this by trimming the stabilizer down and accelerate the nose-down moment. But again, it would only happen in an extreme edge case - high AOA, high power, and clean wing. The problem stems from apparently a not robust enough software behind it to ensure that if the AoA system is malfunctioning MCAS is disabled or restricted in its operation to prevent it from repeatedly activating. AoA vanes are fairly reliable pieces of equipment. I don't think Boeing ever thought that there would be a failure mode in which an AoA vane would malfunction as it did in the case of Lion Air 610. AoA vanes tend to either work or not. They don't "kinda" work or give bad info. It's a vane directly attached to a rheostat. It's extremely simple. There's not much to fail. So that if failed is just as surprising as MCAS existing.
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Post by walterleo on Mar 20, 2019 18:30:23 GMT
Yes and here comes in the role of the FAA: If a once respected government agency hands over its "thinking" to an interested party, no wonder that the FAA did not "think" either. So it is fairly cheap to blame the pilots arguing that they did not what a PPL owner is suposed to do: Cut out the electric trim. But the ATPL pilots are suposed to retract the flaps quite low to save fuel. And now at some hundred feet above the ground while their mount is playing crazy they should read their checklists and recite memory items before touching anything. To come back to the AF copilot who did hold back his sidestick for 3 minutes while the airplane tumbled around at some 15 deg nose up and altimeter winding down. One can argue that this pilot in his glider (he was an experienced glider pilot) would never have done that. But in the airliner he was drilled to fly out a stall and not pushing the (side)stick forward.
Kind regards
Walter
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Post by christrott on Mar 21, 2019 14:07:36 GMT
1) Basic flying is basic flying no matter what the aircraft you're in. If the trim does something you don't think it should, you disconnect it. It's not a PPL v ATPL thing. It's a basic flying thing. You shouldn't have to re-train basic flying skills just because you get into an ATPL. There isn't re-training on the basic operation of the Autopilot when you get a type rating in a given aircraft. It only goes over the SPECIFIC changes between the basic Autopilot functions and that airplane (things like INTERVENTION modes, FMC integration, etc). Memory items also include RUNAWAY TRIM in the Boeing 737. Again, not once did either crew address the apparent uncommanded trim activation.
2) AF 447 - the pilot who held the stick back was not trained on how to deal with the issue presented. PERIOD. The only training received on stalling and on a frozen pitot system were during approach and takeoff. There was no "in cruise" training for stalls. Partly due to his inexperience, he wrongly conflated that training into cruise at high altitude, where the correct action was to trade altitude for speed and not try to fly out of it. In fact, look at all the example you gave - how many accidents or disasters were averted or at least minimized because of the pilot reverting to basic glider piloting skills, sometimes against standard training. I can think of 2 accidents off the top of my head - US Air 1549 and Air Canada 143.
Also, the cruise pilot actively disregarded pleas from the other two crew members to put the nose down. So, it was more than "training" that caused him to freeze up.
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Post by walterleo on Mar 21, 2019 15:49:27 GMT
Because they had to and did read varios pages of the emergency section of their FOM. So it was engrained on them. The CVR did record that.
That other crews saved the day can attributed on other circumstances e.g. flying already higher or less reliance on keeping rules. This saved a MD 11 crew with an electric fire on board doing the right thing: Land immediatly and not reading endless checklists which after 10 minutes say: Land! As happend in the SWISS MD 11
Kind regards
Walter
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Post by George Carty - HJG on Mar 21, 2019 19:11:53 GMT
Didn't the Swissair 111 fire spread so fast that even if the flight crew had decided to land immediately, they couldn't have made it to Halifax before the fire rendered the plane uncontrollable?
George
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Post by christrott on Mar 21, 2019 20:59:02 GMT
Because they had to and did read varios pages of the emergency section of their FOM. So it was engrained on them. The CVR did record that. That other crews saved the day can attributed on other circumstances e.g. flying already higher or less reliance on keeping rules. This saved a MD 11 crew with an electric fire on board doing the right thing: Land immediatly and not reading endless checklists which after 10 minutes say: Land! As happend in the SWISS MD 11 Kind regards Walter And that's where I have a problem Walter - what happened to basic flying skills and training how to deal with basic issues WITHOUT the book? This is what makes it a vicious cycle - Airbus puts in all this automation. People train to rely on the automation. Plane crashes because automation fails. Demands are made for more automation to prevent the automation from failing and not demands for rectifying the issue of inexperienced and poorly trained crews causing the crashes. I'm also not demanding that everyone have 1500 hours before they can fly for a regional (as was done in the US recently). It's about getting the right kind of training and experience. I believe you can safely get that training and experience in less than 1000 hours when done right, and the safety record in the US showed it. The problem started when planes and training stopped emphasizing basic flying skills and started emphasizing system management and combined that with low-time (relatively) crew that was also exposed to high stress and fatigue. Meanwhile, the European and Asian accident rates remain unchanged if not worsening because they continue to introduce "shortcuts" to training (like the "Cruise Pilot") and more and more reliance on automation and external guidance (requiring all approaches to be flown on autopilot, using a precision instrument approach, etc) instead of emphasizing basic hand flying while operating these large aircraft and how to actually problem solve.
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Post by Peter Liddell - HJG Admin on Mar 21, 2019 23:18:12 GMT
Didn't the Swissair 111 fire spread so fast that even if the flight crew had decided to land immediately, they couldn't have made it to Halifax before the fire rendered the plane uncontrollable? George No... It was technically controllable right to impact, the primary flight controls were never compromised. However they had no primary instruments, no autopilot, no lights, smoke too thick to see through and blood toxicity imparing function for the flight crew before the final plunge. If they had elected to skip the fuel dump and do a short approach to yhz they had a good chance at making it... Though no one knows what the fire would of done after depressurization or if the flaps and gear would of dropped normally...
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Post by Herman on Mar 22, 2019 14:51:51 GMT
Interesting discussions here with some valid points being brought up. At times I wondered if this MCAS system was really all that necessary. Would the AOA vane and AOA instrument indication on the flight deck have not been sufficient??
Yes, the point that the MAX8 engine had slightly more power, and was a bit larger was made, but did it actually cause that much more of a pitch control problem as say the previous model of the 737-800.??
During my flying days of General Aviation aircraft (Cessna's and Cherokee's) once the aircraft left the ground and gained speed it was always necessary to apply elevator pitch "trim down" to maintain the proper pitch attitude, so I am certain all pilots no matter what type of aircraft they are flying are aware of that, and are always mentally prepared to apply that pitch trim compensation.
Herman
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Post by walterleo on Mar 22, 2019 15:15:27 GMT
Hi friends:
The public discussion is intoxicated by the serious problems of legal consequences as the lawers always go for the deepest pocket the aircraft manufacturer, the FAA and the airlines are not so unhappy if the problem rests with dead pilots without a pocket.
So far: Even a B 737 Max or an AB 320 neo are still airplanes which can bite if not properly treated. Training, automation, standard procedures AND at the last resort Common Sense and BASIC FLYING SKILLS should avoid a mishap. But as it is very common in life one tries to avoid one reason for mishap will create another reason by overdoing his effort. So it did make good sense to ban authoritarian macho types with disregard for procedures, pure contempt of their crews and treating ATC with "Nobody has to tell me how to fly!". Such types more than once flew into mountains at airports where they had landed hundred times before. But screening out such personalities brought also overrespect for superiors, orders and procedures into the cockpit of our airliners ending up with poor guys searching their FOM while the airplane is diving into the ground or applying procedures which where prescribed but in fatal error or feared more the wrath of the captain (or ATC) than their death.
Kind regards
Walter
Regarding the Swiss Air MD-11 with elctric fire in the cockpit. The Copilot also a Swiss Army Mirage pilot very soon in the drama proposed to land immediatly. The captain said that the cabin still was not ready for landing. Poor captain and all on board: There were many points of the checklist still open. After the tragedy the checklist was changed: The alternative of immediate landing is now on top.
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Post by Peter Liddell - HJG Admin on Mar 24, 2019 17:36:57 GMT
Now I remember why this whole thing about not being trained on a safety system update sounded familiar...
SAS751... MD81 that crashed after ice caused engine surging and the pilots were unaware of a system called ATR (automatic thrust recovery) that moved the thottles back forward without any notification before the pilots could recover from the surging causing the engines to fail and the plane to crash... Luckily with no fatalities
So similar to MCAS... McDonnell Douglas only notified SAS of the system in small note sections buried in the operation manuals after delivery... No pilot training on it at all and SAS never ordered it.
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