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"The pilots of the crashed Ethiopian Airlines flight followed the correct emergency procedures laid out by Boeing but were still unable to stop it crashing, according to a report today.
The crew’s action, if confirmed, would contradict assertions by Boeing that any problems with the electrically powered tail stabiliser on the new 737 Max series can be resolved by carrying out a standard drill"
From the Times today.
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I read an article in the NY times about the procedure for taking over manual control, i.e. switching off the MCAS and manually operating a control wheel. Apparently the control wheel would need a large number of turns to counteract the computer implemented setting and if you were not quick enough, there would be no chance of pulling out of the dive.
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It now seems that "other problems have emerged with the MCAS software" which meant it switched itself back on! (and several times!!!!!)
But Boeing are not concerned with the loss of life, (covered by the Warsaw convention) but the potential loss of customers and the potential loss of orders and compensation for delayed orders and if found at fault, the costs of compensating customer airlines for loss of use of their assets.
As usual, money at the base of it.
All pilots (it seems) will have to undergo simulator training..... and the software fix isn't even fixed yet,
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Boeing would seem to up to their neck in it?
www.bbc.co.uk/news/business-47812225
"Pilots "repeatedly" followed procedures recommended by Boeing before last month's crash of an Ethiopian Airlines flight, according to the first official report into the disaster."
John F might want to give his head a bit of a wobble?
Edited by nick62 on 04/04/2019 at 12:24
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"Pilots "repeatedly" followed procedures recommended by Boeing before last month's crash of an Ethiopian Airlines flight, according to the first official report into the disaster."
John F might want to give his head a bit of a wobble?
Reminds me of an Einstein quote.....
Insanity: doing the same thing over and over again and expecting different results
It will probably be ages before the lawyers finish with this and we get the complete true story. In the meantime my wobbling head will continue to wonder whether a couple of experienced BA pilots in their fifties would have coped better than a couple of relatively inexperienced young pilots in their twenties trained, certified and appraised I know not how, where or when.
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It will probably be ages before the lawyers finish with this and we get the complete true story. In the meantime my wobbling head will continue to wonder whether a couple of experienced BA pilots in their fifties would have coped better than a couple of relatively inexperienced young pilots in their twenties trained, certified and appraised I know not how, where or when.
There is very good evidence, that the automatic (motorised) trim had put the tail-plane jackscrew at full "nose-down" and in the subsequent dive, the air pressure force on this was such that it was nigh-on impossible for a human to rotate the manual trim wheel to rectify the fault.
Imagine driving a car at 200 mph in reverse and trying to close one of the doors (with both arms)?
This is a quote from today's Seattle Times:
".........the Ethiopian pilots most likely were unable to carry out that last instruction in the Boeing emergency procedure — because they simply couldn’t physically move that wheel against the heavy forces acting on the tail.
“The forces on the tail could have been too great,” Lemme said. “They couldn’t turn the manual trim wheel.”
The stabilizer in the Ethiopian jet could have been in an extreme position with two separate forces acting on it:
- MCAS had swiveled the stabilizer upward by turning a large mechanical screw inside the tail called the jackscrew. This is pushing the jet’s nose down.
- But the pilot had pulled his control column far back in an attempt to counter, which would flip up a separate movable surface called the elevator on the trailing edge of the tail.
The elevator and stabilizer normally work together to minimize the loads on the jackscrew. But in certain conditions, the elevator and stabilizer loads combine to present high forces on the jackscrew and make it very difficult to turn manually.
As the jet’s airspeed increases — and with nose down it will accelerate — these forces grow even stronger.
In this scenario, the air flow pushing downward against the elevator would have created an equal and opposite load on the jackscrew, a force tending to hold the stabilizer in its upward displacement. This heavy force would resist the pilot’s manual effort to swivel the stabilizer back down.
This analysis suggests the stabilizer trim wheel at the Ethiopian captain’s right hand could have been difficult to budge. As a result, the pilots would have struggled to get the nose up and the plane to climb.
If after much physical exertion failed, the pilots gave up their manual strategy and switched the electric trim system back on — as indicated in the preliminary reports on the Ethiopian flight — MCAS would have begun pushing the nose down again.
Boeing on Wednesday issued a statement following the first account, published Tuesday night by The Wall Street Journal, that the Ethiopian pilots had followed the recommended procedures.
“We urge caution against speculating and drawing conclusions on the findings prior to the release of the flight data and the preliminary report,” Boeing said."
Edited by nick62 on 04/04/2019 at 21:39
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This sounds familiar
Since I don't read accident reports routinely, I probably waited for the film to come out. Can't remember what it was called, but Denzell Washington was an alcoholic pilot caught in. IIRC, the above situation.
He rolled the aircraft, flying inverted, so the nose-down force from the elevator was converted to nose up force,
I've only flown gliders so I don't know if it is in fact possible to avoid a stall in that situation, though it is in the movies.
Dunno if this event was pure fiction or based on a real "save"
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It now seems that "other problems have emerged with the MCAS software" which meant it switched itself back on! (and several times!!!!!)
But Boeing are not concerned with the loss of life, (covered by the Warsaw convention) but the potential loss of customers and the potential loss of orders and compensation for delayed orders and if found at fault, the costs of compensating customer airlines for loss of use of their assets.
As usual, money at the base of it.
All pilots (it seems) will have to undergo simulator training..... and the software fix isn't even fixed yet,
You may recall the Challenger disaster, when a space shuttle exploded on launch. The reason was that they flew when it was very cold, and the seals in the boosters were not rated for the low temperatures experienced that day. The managers would have known it was too cold, but they went ahead anyway, presumably due to pressure to complete a mission. In my experience many senior managers in companies and institutions are more concerned with their own status, image and wealth than the customers. Human nature I guess.
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I'm probably terribly naive, but can someone explain to me:
Is it possible, or not, for a pilot to execute a successful take-off in a plane (like this one) by flying the plane 100% manually?
If it IS possible, then why are pilots (and their backup copilot) not trained to be competent to do this?
I mean, how likely would a pilot BE to actually cause the plane to stall ?
Why not just train pilots how to react to WARNING systems, rather than installing systems which actively intervene, and the pilots then instead having to be trained (or not?) how to react when those actively-intervening systems malfunction?
Or is it that these modern planes are too complex and/or unstable to achieve a takeoff without computer assistance (or indeed completely under computer control) ?
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As with most things today - it's all about profit.
Modern aircraft used by airlines are so automated by flight control systems that it is possible that a pilot will only hand-fly the aircraft briefly at take-off and in the final stages of landing. These systems are there mainly so that the cost of flying the aircraft is kept down by the airline, ie fuel consumption and keeping engine wear down as much as possible, by for example using only the minimum necessary engine power to achieve the take-off given take-off weight, runway length and condition, weather wet or dry, temperature, altitude of runway and loads of other stuff as well. The automated flight director system sets the auto-throttles to do all that. Older pilots call recently trained pilots "play station pilots"
Edited by focussed on 04/04/2019 at 23:40
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I wonder how this will work out if the software in the promised self-driving cars is similar? That will be something to look forward to .....
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HandCart: According to a R4 news report, the software adjusted the control surfaces by 1.5 degrees to correct a perceived fault. It was supposed to stop there, but reset itself, added another 1.5 degrees and so on, and the pilots were unable to manually override the software. So it was a very real fault that could not be recovered manually. Investigations are underway, so that has yet to be confirmed for certain.
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The European Aviation and Space Agency (EASA) certified the plane as safe in part because it said additional procedures and training would “clearly explain” to pilots the “unusual” situations in which they would need to manipulate a rarely used manual wheel to control, or “trim,” the plane’s angle.
Those situations, however, were not listed in the flight manual, according to a copy from American Airlines seen by Reuters.
(The flight manual has some 1400 pages)
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Leif:
I'm kind of inferring then that these planes are so tricky to fly that the software is designed to recognise that if during takeoff there is a REAL problem, which it deems is so serious and rapid that a pilot flying 100% manually would never be able to notice/act upon/recover from, it then actively intervenes.
My question then would be, why should problems of SUCH severity arise anyway? Why don't they just make the planes take flight in a more foolproof fashion in the first place?
It's like being in the 1970s and going round a wet roundabout in a Porsche 911 rather than a Renault 4.
But my understanding is that there may not even have BEEN a REAL problem - the 'problem' could have been conflicting info from different sensors feeding data into the software.
In which case you have electronics and software being the things that actually CREATED a problem where none actually existed, and then on top of that are implemented in such a way that the pilots cannot switch-over the jackscrews' electrical feed from the computer, to some manual control instead.
Planes are supposed to be up in the air. The ground is ultimately the biggest hazard. So any 'thing' that will force a plane to point downwards should be designed in the first place to be able to be disconnected from a computer's sole control and returned to the pilot's control, just in case. Should be a fundamental law.
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HandCart: The engines on the new 737 variant were front heavy, causing the nose to tilt. The MCAS was designed to correct the trim, however by all accounts there was a design flaw in the software which was not picked up during certification. I think the underlying issue was false data from a sensor.
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From the information I heard, on the two planes that crashed, only ONE (attack angle) sensor was used for this data. It was an extra cost option to have more than one sensor.
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The engines on the new 737 variant were front heavy, causing the nose to tilt. The MCAS was designed to correct the trim,
To me, that represents a deliberate design fault. Why put a plane together with an intrinsic imbalance which needs a special correction device, especially one which can't be contained?
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The engines on the new 737 variant were front heavy, causing the nose to tilt. The MCAS was designed to correct the trim,
To me, that represents a deliberate design fault. Why put a plane together with an intrinsic imbalance which needs a special correction device, especially one which can't be contained?
Because it was cheap...................
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To me, that represents a deliberate design fault. Why put a plane together with an intrinsic imbalance which needs a special correction device, especially one which can't be contained?
They went for a development of a 50+yo design (737 first flew in 1967) rather than cost of something new. Allowed much of design to be 'grandfathered' based on previous models. Furthermore they wanted pilots to be able to fly it without expensive type rating training and simulator sessions and to fly it interchangeably with the previous generation.
Sticking big new high efficiency turbofans on a frame designed for sixties turbojets, and with limited ground clearance for those, presented a challenge. The solution put the engines well forward with result that under some circumstances lift from the nacelles could cause a pitch up and stall. MCAS was designed to overcome that problem.
Wags have mentioned lipstick on a pig (the 737 was nicknamed 'pig' by spotters in seventies).
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.........and the pilots were unable to manually override the software. So it was a very real fault that could not be recovered manually. Investigations are underway, so that has yet to be confirmed for certain.
Possibly, but having read this......
www.b737.org.uk/mcas.htm#stcs
....they should have been able to switch off the rogue anti-stall kit (MCAS) by using the STAB TRIM CUTOUT switches. I am still wondering if these youngsters had sussed this out, or whether said switches didn't work.. These are basic questions which need answers.
For a simplistic comparison, my Audi has daytime running lights which are switched on automatically. It is possible to turn them off, but if you don't know how, you have to either read the instructions or spend much time fiddling with the MMI wheel and buttons. DRLs are briefly mentioned on P 73 of the 370 page Owner's Manual, which refers you to the MMI (Multi Media Interface manual. This has 320 pages. How to switch the DRLs on and off is found on page 255. During my first drive of the car, without having read these manuals, I would have struggled to work out how to switch them off while driving I can easily understand that the young pilots might not have been as au fait with the controls of this newish bit of kit as they should have been. If not, they probably had little time to locate and read Boeing's instructions. If I have over 600 pages to digest in order to become thoroughly familiar with my machine, goodness know how much reading a 737 pilot has to do - and possibly not even in his/her first language.
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Have you got a Boeing pension?
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Have you got a Boeing pension?
Or a significant holding of Boeing stock?
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Some of the comments are veering towards silly..
( a couple of BA pilots would have recovered the plane) really???? The inference to me from those remarks is that "only" a BA pilot could have recovered the aircraft. WRONG WRONG AND WRONG.
Niki Lauda went on a BOEING simulator (after a lot of pressure)to prove to Boeing that no pilot alive could have recovered the Lauda Air 757 when the Boeing system reverse thrusters engaged at high speed/altitude....read the report.]
Lauda stated, "what really annoyed me was Boeing's reaction once the cause was clear. Boeing did not want to say anything."[18] Lauda asked Boeing to fly the scenario in a simulator that used different data as compared to the one that Lauda had performed tests on at Gatwick airport.[22] Boeing initially refused, but Lauda insisted, so Boeing granted permission. Lauda attempted the flight in the simulator 15 times, and in every instance he was unable to recover. He asked Boeing to issue a statement, but the legal department said it could not be issued because it would take three months to adjust the wording. Lauda asked for a press conference the following day, and told Boeing that if it was possible to recover, he would be willing to fly on a 767 with two pilots and have the thrust reverser deploy in air. Boeing told Lauda that it was not possible, so he asked Boeing to issue a statement saying that it would not be survivable, and Boeing issued it. Lauda then added, "this was the first time in eight months that it had been made clear that the manufacturer [Boeing] was at fault and not the operator of the aeroplane [or Pratt and Whitney]."[18]
When the Federal Aviation Administration (FAA) of the United States asked Boeing to do tests activating the thrust reverser in flight,[23] the FAA had allowed Boeing to establish the tests of the thrust reverser. Boeing had insisted that a deployment was not possible in flight. In 1982 Boeing established a test where the aircraft was slowed to 250 knots, and the test pilots then used the thrust reverser. The control of the aircraft had not been jeopardized. The FAA accepted the results of the test.[24]
The Lauda aircraft was traveling at a high speed when the thrust reversers deployed, causing the pilots to lose control of the aircraft. James R. Chiles, author of Inviting Disaster, said, "the point here is not that a thorough test would have told the pilots Thomas J. Welch and Josef Thumer [sic] what to do. A thrust reverser deploying in flight might not have been survivable, anyway. But a thorough test would have informed the FAA and Boeing that thrust reversers deploying in midair was such a dangerous occurrence that Boeing needed to install a positive lock that would prevent such an event." As a result of their findings during the investigation process of Lauda Flight 004, additional safety features such as mechanical positive locks were mandated to prevent thrust reverser deployment in flight
The Ethiopian PILOT had 8000 hours on 737's, not all pilots in the BA fleet have that many. Some have many more, but many have less.
At the base of all this, are several very real facts.
There were aircraft defects, there was a lack of information on the differences in the aircraft between the "old" type and the 737 max.
Let us please not forget that 354 people died because of greed/corruption and design faults.
Edited by oldroverboy. on 05/04/2019 at 15:13
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Possibly, but having read this......
www.b737.org.uk/mcas.htm#stcs
....they should have been able to switch off the rogue anti-stall kit (MCAS) by using the STAB TRIM CUTOUT switches. I am still wondering if these youngsters had sussed this out, or whether said switches didn't work.. These are basic questions which need answers.
John,
If you want to understand this more fully I'd suggest you set an afternoon aside and read through the various threads on The Professional Pilots Rumour Network around the Ethiopian crash and wider 73 MAX issues. Current theory seems to be that 'these youngsters' did exactly what the drill said and still crashed. Some contributors relate experience on the SIM for earlier versions of the 737 where the STAB TRIM goes rogue and requires considerable physical effort on both the elevators and the manual trim . Others refer to a now deleted you tube item where a pilot tried the Lion Air/Ethiopian scenario in a MAX simulator and couldn't fly out of it. It was deleted at request of his employers because it wasn't a properly planned and authorised exercise.
That said the idea that too many pilots, probably including many who've been flying for 25+ years can no longer fly accurately on 'raw data' - view from the window and or basic blind flying instruments - is well founded. AF448, the Air France Airbus that crashed in the Atlantic, was a case in point. This AAIB report (pdf on AAIB website) regarding mishandled go-around by a UK registered 757 at Newcastle is another example. Anybody who reads the AAIB bulletin every month will see other examples.
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Brompt - thanks for your enlightening comments about the additional lift from the nacelles.
Okay so I can see how the 737 MAX has been a bodge job, but your regards your line:
"the idea that too many pilots, probably including many who've been flying for 25+ years can no longer fly accurately on 'raw data' - view from the window and or basic blind flying instruments - is well founded"
- Does that mean it's likely that the majority of modern planes ALSO have intrinsic design flaws or imbalances, that are being 'worked-around' by automated systems which, fortunately, are more reliable...?
- Or is it something else?
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Brompt - thanks for your enlightening comments about the additional lift from the nacelles.
Okay so I can see how the 737 MAX has been a bodge job, but your regards your line:
"the idea that too many pilots, probably including many who've been flying for 25+ years can no longer fly accurately on 'raw data' - view from the window and or basic blind flying instruments - is well founded"
- Does that mean it's likely that the majority of modern planes ALSO have intrinsic design flaws or imbalances, that are being 'worked-around' by automated systems which, fortunately, are more reliable...?
- Or is it something else?
But if the computers say no, then it's no, at least until you can switch hal off (2001 a space odyssey) original novel, not the film
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- Does that mean it's likely that the majority of modern planes ALSO have intrinsic design flaws or imbalances, that are being 'worked-around' by automated systems which, fortunately, are more reliable...?
- Or is it something else?
Something else. Many airlines Standard Operating Procedures (SOPs) require the autopilot to be on from shortly after tale off until just before landing. Climb/descent and navigation are maintained by pressing buttons and turning dials rather the using the control column and rudder pedals together with the throttles. Pilots are attuned to following the magenta line on the flight deck display and lose the basic stick and rudder skills they learned during initial training on light planes. When the automatics drop out they can't fly the plane. Pretty much what happened to Air France 447. All they had to do was lower the nose following their basic blind flying instruments, set known power for level flight and then work the problem that caused the automatics to drop out.
I believe it's called the automation paradox. Stuff is automated to make it safer but reliance on the automation robs people of the skills needed when the automation fails.
Edited by Bromptonaut on 06/04/2019 at 09:18
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Brompt - thanks for your enlightening comments about the additional lift from the nacelles.
Okay so I can see how the 737 MAX has been a bodge job, but your regards your line:
"the idea that too many pilots, probably including many who've been flying for 25+ years can no longer fly accurately on 'raw data' - view from the window and or basic blind flying instruments - is well founded"
- Does that mean it's likely that the majority of modern planes ALSO have intrinsic design flaws or imbalances, that are being 'worked-around' by automated systems which, fortunately, are more reliable...?
- Or is it something else?
By all accounts this fault was due to inadequate verification testing. Some planes are inherently unstable and cannot be flown without automated systems. However, it has been claimed that the Miracle on the Hudson would have been the crash in the Hudson without fly by wire. The Airbus systems might have permitted a safer water ditching.
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John,
If you want to understand this more fully I'd suggest you set an afternoon aside and read through the various threads on The Professional Pilots Rumour Network
Sadly I can't, as 'this site cannot provide a secure network'
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Sadly I can't, as 'this site cannot provide a secure network'
How odd. It's https// same as this site. In any event it's only a chat forum like this one only much bigger. You're not giving it your bank details.
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The pilots died and all you can do is insult them. I suggest you wait for the results of the investigation before apportioning blame.
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A bit reminiscent of the Toyota "unintended acceleration die-by-wire" thing, though that seemed to go quiet without a convincing conclusion.
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Interim report now published:
http://www.ecaa.gov.et/documents/20435/0/Preliminary+Report+B737-800MAX+,%28ET-AVJ%29.pdf
While the armchair quarterbacks keep saying why didn't crew do X,Y and Z they're not sitting on a flightdeck with multiple alarms going off and an aircraft that won't behave as it should.
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Thanks, most interesting. More questions....this from 'Flight Global'.
....But the inquiry is likely to concentrate on the reasons why the crew – having flown the aircraft for nearly 3min with the cut-off engaged – subsequently resorted to the electric trim, preceding another automatic nose-down command which pushed the jet into its final fatal dive....
Also, why was the overspeed warning ignored?. The throttles were apparently set high throughout. The faster you go, the more difficult - .and apparently impossible in this case - it is to trim a stabilizer owing to the wind force. A single electric motor is used. Was it up to scratch? Had the jackscrew assembly been oiled recently? etc etc
Edited by John F on 07/04/2019 at 19:40
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....But the inquiry is likely to concentrate on the reasons why the crew – having flown the aircraft for nearly 3min with the cut-off engaged – subsequently resorted to the electric trim, preceding another automatic nose-down command which pushed the jet into its final fatal dive....
Also, why was the overspeed warning ignored?. The throttles were apparently set high throughout. The faster you go, the more difficult - .and apparently impossible in this case - it is to trim a stabilizer owing to the wind force. A single electric motor is used. Was it up to scratch? Had the jackscrew assembly been oiled recently? etc etc
The overspeed warning may not have been ignored. The crew had at least three aural/physical warnings - stick shake, GPWS 'don't sink' and the overspeed 'clacker'.
Which one to prioritise?
They re-instated electric trim as last resort because the physical effort of trimming manually was apparently beyond them.
Yes it's possible a captain like Sullenburger could have used have basic instruments and flown known attitude/power/trim to control the machine while working the problem but sadly modern pilots are not trained to do that.
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Yes it's possible a captain like Sullenburger could have used have basic instruments and flown known attitude/power/trim to control the machine while working the problem but sadly modern pilots are not trained to do that.
I find that hard to believe. A modern fly-by-wire plane can virtually fly itself. Surely training and ongoing appraisal of a pilot is not only to understand how it does it, but also to frequently practice coping with things when they go wrong. I think at least one of the two pilots should have had the experience and training of a Sullenberger. It surprises me that you can become a captain with such responsibility while still in your twenties.
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I don't think there's much more mileage in this thread.
As it's not a motoring matter, I'll either close it this evening or - if people really want to continue it - move it to General discussion.
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Thanks Avant. PLease could you move it to General Discussion.
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While i am aware that it is not motoring, "BUT" only transport, I feel that the wider lessons, including automation in cars, (cameras on cars and automated braking) make it a useful subject. It is transport after all and does affect lots of us.
That said, I hope that when the full facts are known and the full culpability is known that i (we) would be allowed to add to it.
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That said, I hope that when the full facts are known and the full culpability is known that i (we) would be allowed to add to it.
That's my point too; it's a developing scenario and there will be more to discuss as full facts emerge.
Whether I have persistence to keep correcting John's misapprehensions is another question........
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I don't think there's much more mileage in this thread.
As it's not a motoring matter, I'll either close it this evening or - if people really want to continue it - move it to General discussion.
It does seem that some are expressing views based on prejudices, whilst others including myself are going by unconfirmed reports. Perhaps it would/ be best to wait for the official report which will have the benefit of facts.
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I find that hard to believe. A modern fly-by-wire plane can virtually fly itself. Surely training and ongoing appraisal of a pilot is not only to understand how it does it, but also to frequently practice coping with things when they go wrong.
The 737MAX is NOT a fly by wire aircraft.
Pilots are certainly trained in the SIM to fly out of a range foreseeable technical issues. In real world they do not always manage to diagnose the problem and fly the recovery when all hell breaks out on the flight deck.
There simply are not enough pilots in the world for every Captain to have the experience etc of Sullenburger who was approaching retirement at time of landing in Hudson. Command before the age of 30 is not uncommon.
It is a fact that there are serious concerns in the aviation industry about pilots who operate the knobs and buttons and lack the skills to hand fly say from downwind leg to landing. They should be practising that from time to time but SOPs say the automatics fly until final stages of approach. If you can overcome your security issues with PPRUNE you'll see it discussed there. Alternatively google 'children of the magenta line'.
The crucial thing here is that the failure apparently experienced on the two crashed 737MAX could have been hi-lighted and required to be trained for in the SIM. Boeing didn't do that.
I'll let history be judge of whys and wherefores of that decision.
Edited by Bromptonaut on 08/04/2019 at 16:44
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I find that hard to believe. A modern fly-by-wire plane can virtually fly itself. Surely training and ongoing appraisal of a pilot is not only to understand how it does it, but also to frequently practice coping with things when they go wrong.
The 737MAX is NOT a fly by wire aircraft.
If that's not a misapprehension, I don't know what is.
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If that's not a misapprehension, I don't know what is.
In what sense is an aircraft derived from a sixties design and with the controls connected to ailerons, elevators and rudder, by cables and pulleys a fly by wire aircraft?
A major issue with the Ethiopian crash was inability to use the manual trim wheel. I've read somewhere that in the Lion Air incident that preceded that company's MAX crash it was a supernumary crew member in the jump seat watching the trim wheel, connected to the tailplane by cables, moving that helped solve the problem.
Edited by Bromptonaut on 19/04/2019 at 13:15
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If that's not a misapprehension, I don't know what is.
In what sense is an aircraft derived from a sixties design and with the controls connected to ailerons, elevators and rudder, by cables and pulleys a fly by wire aircraft?
In the sense that the cables of the 'manual reversion' systems are rarely if ever used in a modern fly-by-wire plane. And I doubt very much if pilots practise using them in real life situations. As another simplistic comparison imagine coasting down a mountain pass in neutral after engine failure. You will soon need a surprisingly hard push on the pedal to brake. A new driver could panic and not push hard enough if they had no experience of such a scenario.
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John F, what exactly is your agenda here, (and unless I'm mistaken you also seem to have a poor grasp of engineering principles and mechanics)?
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John F, what exactly is your agenda here, (and unless I'm mistaken you also seem to have a poor grasp of engineering principles and mechanics)?
It's to believe what he wants and even if shown proof then he won't change his mind.
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John F, what exactly is your agenda here
I don't have an 'agenda', apart from sheer curiosity.
It's to believe what he wants and even if shown proof then he won't change his mind.
'Belief' and 'believe' are not words I use. I prefer facts, 'truth' and 'think'. When the facts change, I change my mind (Keynes). What some people call 'proof' is often just opinion.
I am merely discussing the possible reasons why, of all the dozens of planes flying regularly with this technology, only two have crashed. Hopefully the final report will tell us, but in the meantime I see no reason not to respond to and take part in a discussion as to how and why they crashed. That's what this forum is for. It is a matter of fact that most plane crashes are due to human error, often that of the pilot(s), and so far it seems to me that their incompetence, for whatever reason; lack of training/practice; challenging and/or faulty control systems, caused this one. Obviously if there was a mechanical fault like a failed jackscrew nut (Alaska 261...they even tried to fly it upside down), no pilot on earth could have landed it.
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I am merely discussing the possible reasons why, of all the dozens of planes flying regularly with this technology, only two have crashed.
So far Boeing have delivered approx 370, most of them in last 12 months.
As well as two that crashed there was serious incident involving the Lion Air machine in sector before its accident. According to Aviation Herald there's been one other incident where there were instrumentation failures leading pilots to descend into into VMC - where they could see horizon etc. There are also a significant number of bird strikes.
The initial trigger in each case seems to have been a faulty Angle of Attack indicator. As there are only two of these it may take time to identify the faulty one. Some airlines ordered an extra cost option where AOA disagree was highlighted on the main display in front of pilots. In absence of that working the problem and ascertaining which one is 'rogue' may take time and attention. Pilot on rogue's side will get stick shake and, if they're in a mode where MCAS operates, it may start to trim the tailplane nose down. In both Lion Air and Ethiopian crashes that process got ahead of the crew. If they'd had proper training, including a simulator session to alert them to MCAS risks and an SoP to deal with them then your accusation of incompetence might hold water. Failure of manufacturer to properly document MCAS and train for it is NOT the fault of the crew.
Sullenburger, mentioned upthread was an exceptional pilot. He'd started on gliders and flown F4 Phantoms in the military before joining civil aviation. Well before the Hudson ditching he's been involved in flight safety development. As he said in aftermath he'd spent 40 years making small deposits at the bank of experience. When he needed to make a large withdrawal he sufficient credit.
These planes are designed to be flown by an average crew. Two average crews have died in crashes.
Let's wait for proper outcomes before condemning them.
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In the sense that the cables of the 'manual reversion' systems are rarely if ever used in a modern fly-by-wire plane. And I doubt very much if pilots practise using them in real life situations.
In the 737 the cables, pulleys etc are the only means by which the control surfaces are moved. They have hydraulic or electrical power assistance analogous to power steering in a car. That does not make it a fly by wire aircraft. Neither does a high degree of flight deck automation where pressing buttons and turning dials are substitutes for stick/rudder/throttles.
This thread on PPRUNE albeit a few years ago suggests there is an element of manual reversion training - ie simulated failure of the hydraulic assistance.
If it was fly by wire like its rival the Airbus A320, where there are no cables and pulleys and the pilot's control inputs are transmitted digitally by wire, then it wouldn't be able to be certified based on rights 'grandfathered' from the original 1967 model.
I understand that one difference on the MAX is that the spoilers are deployed electronically to improve braking/shorten ground roll on landing but it remains essentially a sixties era control system.
Edited by Bromptonaut on 23/04/2019 at 20:58
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Further news that Boeing were warned prior to the second crash (by US pilots):
www.bbc.co.uk/news/business-48281282
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It seems that every day brings some more news of Boeing's incompetence and downright dishonesty.
Now it emerges that the information that Boeing supplied to the manufacturers to program the 737-max flight simulators was wrong. Using Boeing's information, the simulators would not reproduce the problem that is suspected of causing the two crashes.
https://www.seattletimes.com/business/boeing-discovers-flaw-in-sought-after-737-max-simulator-the-same-kind-that-ethiopian-airlines-had/
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If you want a real shock - watch this video, ok it's long and a bit drawn out but you'll be up to date with how quality control and just about any control is sidelined by Boeing and this particular subcontractor - and the FAA gets in on it too.
There are adverts in the middle - just fast forward past them and continue.
A woman who was on the audit team sent from Boeing to the subcontractor describes that the team were threatened with being shot - that's what she said happened.
youtu.be/vWxxtzBTxGU
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Latest report, Boeing admits 'mistakes' and apologises:
https://www.standard.co.uk/news/world/boeing-admits-cockpit-warning-system-mistake-before-apologising-to-families-of-victims-who-died-in-a4168646.html
I quote JohnF
The pilots were fairly green, and I wonder about how easy it is to get a pilot's qualification elsewhere in the world. I would lay odds that if it had been a couple of BA pilots they would have coped. A bit like being still able to drive if your clutch cable snaps?
I guess inferior foreign pilots and standards wasn’t the cause then.
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IAG, group comprising BA, Iberia and various other outfits has signed a letter of intent for 200 737 MAX aircraft. Not firm orders but as article points out Airbus simply cannot meet demand for medium range <220 seaters on its own.
https://www.aerotime.aero/parisaishow/22756-breaking-iag-signs-deal-for-200-boeing-737-max
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Some more interesting comments condemning both Boeing & the FAA from someone who has "been there, done it and got the T-shirt":
www.bbc.co.uk/news/business-48631362
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The European Union Aviation Safety Agency (EASA)
has told Boeing to make five changes to the airliner before it can return to service. They're mostly consistent with the FAA's requests, including improvements to the angle of attack sensors, training, manual trim controls and a software flaw linked to a lagging chip. However, the EU regulators also want Boeing to address a previously unmentioned issue with the autopilot failing to switch off in some emergencies -- it might not give pilots enough time to prevent a stall.
Oh - terrific , a bit like being unable to turn off the cruise control on your car!
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I wonder if JohnF has seen the latest news?
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This thread has long run its course. Now another one has started up.
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