BB solves JT 610 crash
Sure, it seems there might be a problem with the MCAS. I’m assuming the FCOM vol.2 is ‘light on’ with information on this new system. I would also like to think that Boeing covered all eventualities with this system and were satisfied that the Memory Items would suffice.
Lets face it, both Airspeed Unreliable and Runaway Stabilizer have the pilot remove automation and Fly the aircraft. Simple stuff.
Sadly and with all information so far, I think both accidents were avoidable.
Lets face it, both Airspeed Unreliable and Runaway Stabilizer have the pilot remove automation and Fly the aircraft. Simple stuff.
Sadly and with all information so far, I think both accidents were avoidable.
2. The FCOM is mute on the MCAS; No mention is made of it at all except in Brazil apparently. Their regulator didn't accept Boeing's assurances on the subject and hence required at least some crew training on MCAS.
3. Boeing allowed a hidden input to a secondary, but very powerful flight control based on the data from a single source.
4. Boeing maintains that the runaway stabliser checklist adequately addresses inappropriate MCAS activation.
5. Boeing's runaway stabiliser checklist starts with the condition statement “uncomanded stabiliser trim movement occurs CONTINUOUSLY”.
6. The MCAS operates in slow 9.2 second bursts, then pauses for five seconds, then acts again.
7. Depending on your english skills, the MCAS may or may not satisfy your personal trigger threshold for an actual runaway stab. I have had an unrelated stab runaway and it was neither continuous nor as trained.
8. Boeing characterised a MCAS event as less than catastrophic, hence justified their reliance on a single sensor, and a single data path, despite even that being outside the letter of FAR 25
9. Being provides no useful guidance on the ramifications of flight control malfunctions in a holistic sense. There is no mention made of elevator load relief limiting elevator deflection at speeds >300 kts. Nor is there guidance on configuration changes, Nor how to interpret an apparent unreliable airspeed/stall warning on take-off.
10. Try to handle a challenging event with the stick shaker buzzing away and the trim moving in opposition to your control inputs the way the speed trim system does on every take-off and then determine that you have another unrelated failure that needs immediate action.
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1.: A very minor point: FCOM is now contained in one volume
2. The FCOM is mute on the MCAS; No mention is made of it at all except in Brazil apparently. Their regulator didn't accept Boeing's assurances on the subject and hence required at least some crew training on MCAS.
3. Boeing allowed a hidden input to a secondary, but very powerful flight control based on the data from a single source.
4. Boeing maintains that the runaway stabliser checklist adequately addresses inappropriate MCAS activation.
5. Boeing's runaway stabiliser checklist starts with the condition statement “uncomanded stabiliser trim movement occurs CONTINUOUSLY”.
6. The MCAS operates in slow 9.2 second bursts, then pauses for five seconds, then acts again.
7. Depending on your english skills, the MCAS may or may not satisfy your personal trigger threshold for an actual runaway stab. I have had an unrelated stab runaway and it was neither continuous nor as trained.
8. Boeing characterised a MCAS event as less than catastrophic, hence justified their reliance on a single sensor, and a single data path, despite even that being outside the letter of FAR 25
9. Being provides no useful guidance on the ramifications of flight control malfunctions in a holistic sense. There is no mention made of elevator load relief limiting elevator deflection at speeds >300 kts. Nor is there guidance on configuration changes, Nor how to interpret an apparent unreliable airspeed/stall warning on take-off.
10. Try to handle a challenging event with the stick shaker buzzing away and the trim moving in opposition to your control inputs the way the speed trim system does on every take-off and then determine that you have another unrelated failure that needs immediate action.
That Boeing fudged FAR25 and permitted a single failure point and self classified the risk as non-catastrophic will likely get the attention of the investigators.
Excellent information mate.
Point 1, there is still a Vol.2, systems description it’s just been rolled into the one manual.
Unfortunately, I don’t have access to your points 2 and 3. I’ll take your word for it🙂.
Point 4, I would have thought so and I hope that goes in Boeing’s favour.
Point 5, how long would you wait to determine continuously?
Point 6, same as 2 and 3.
Point 7, even though your Runaway Stabilizer event didn’t meet the condition statement, did you complete the Memory Items? Boeing admits that it is not possible to develop checklists for all conceivable situations.
Points 8 and 9, I don’t have access to that information. I will say though that I like the ‘less is more’ philosophy in the Vol.2😉. It allows us to just concentrate more on flying and being Pilots not Engineers.
Point 10, I agree. Certainly a challenging event, but very doable with good discipline, standards and training. Remove the automation, set more blue than brown on the PFD, with the appropriate thrust then trim. If the trim is running against the grain do something about it, maintain aircraft control then analyse the situation.
Again, thank you for the info and making me hit the book (not books) 😉
Point 1, there is still a Vol.2, systems description it’s just been rolled into the one manual.
Unfortunately, I don’t have access to your points 2 and 3. I’ll take your word for it🙂.
Point 4, I would have thought so and I hope that goes in Boeing’s favour.
Point 5, how long would you wait to determine continuously?
Point 6, same as 2 and 3.
Point 7, even though your Runaway Stabilizer event didn’t meet the condition statement, did you complete the Memory Items? Boeing admits that it is not possible to develop checklists for all conceivable situations.
Points 8 and 9, I don’t have access to that information. I will say though that I like the ‘less is more’ philosophy in the Vol.2😉. It allows us to just concentrate more on flying and being Pilots not Engineers.
Point 10, I agree. Certainly a challenging event, but very doable with good discipline, standards and training. Remove the automation, set more blue than brown on the PFD, with the appropriate thrust then trim. If the trim is running against the grain do something about it, maintain aircraft control then analyse the situation.
Again, thank you for the info and making me hit the book (not books) 😉
Excellent information mate.
Point 1, there is still a Vol.2, systems description it’s just been rolled into the one manual.
Unfortunately, I don’t have access to your points 2 and 3. I’ll take your word for it🙂.
Point 4, I would have thought so and I hope that goes in Boeing’s favour.
Point 5, how long would you wait to determine continuously?
Point 6, same as 2 and 3.
Point 7, even though your Runaway Stabilizer event didn’t meet the condition statement, did you complete the Memory Items? Boeing admits that it is not possible to develop checklists for all conceivable situations.
Points 8 and 9, I don’t have access to that information. I will say though that I like the ‘less is more’ philosophy in the Vol.2😉. It allows us to just concentrate more on flying and being Pilots not Engineers.
Point 10, I agree. Certainly a challenging event, but very doable with good discipline, standards and training. Remove the automation, set more blue than brown on the PFD, with the appropriate thrust then trim. If the trim is running against the grain do something about it, maintain aircraft control then analyse the situation.
Again, thank you for the info and making me hit the book (not books) 😉
Point 1, there is still a Vol.2, systems description it’s just been rolled into the one manual.
Unfortunately, I don’t have access to your points 2 and 3. I’ll take your word for it🙂.
Point 4, I would have thought so and I hope that goes in Boeing’s favour.
Point 5, how long would you wait to determine continuously?
Point 6, same as 2 and 3.
Point 7, even though your Runaway Stabilizer event didn’t meet the condition statement, did you complete the Memory Items? Boeing admits that it is not possible to develop checklists for all conceivable situations.
Points 8 and 9, I don’t have access to that information. I will say though that I like the ‘less is more’ philosophy in the Vol.2😉. It allows us to just concentrate more on flying and being Pilots not Engineers.
Point 10, I agree. Certainly a challenging event, but very doable with good discipline, standards and training. Remove the automation, set more blue than brown on the PFD, with the appropriate thrust then trim. If the trim is running against the grain do something about it, maintain aircraft control then analyse the situation.
Again, thank you for the info and making me hit the book (not books) 😉
Regarding point four...Not going to go in Boeing's favour, I'm afraid. Hence the grounding, several investigations and several regulators demanding full disclosure of the entire flight test results and every change from the NG that we fly.
On point 5, I don't know. Would you even detect the first few seconds if normal speed trim activity had desensitised you somewhat? And the word continuously means “unbroken”. The word continually (I was reminded today) is a more accurate depiction of MCAS, and indeed other trim failure modes.
The larger point is that in the current tech writing practice much value is placed on economy of words.
My first pilot manual, Stairway to Heaven claimed that sometimes words have two meanings.
We all know that flexibility is the key to air power, and that ambiguity is the key to flexibility, but perhaps not so much when it comes to procedures.
Point 7...It was a long time ago, but it occured slowly in the mid flight levels on climb while I was hand flying. Not an electrical runaway, but rather a brake failure coupled with wear in the jackscrew. The stab trim would run about 1 1/2 turns in opposition to slight pitch control inputs, even after hitting the cutouts. While we found that fascinating we did in fact complete the NNC recalls (recall them?) and did a 360° and got the hell outta there. Maybe it was a 540? Anyway...Not all runaways are dramatic sounding or feeling. At least initially.
I wish I hadn’t skipped those English classes at school, doh! 😉
By your knowledge and writing I think I know you, is your ‘local’ the Regatta hotel?
Cheers
By your knowledge and writing I think I know you, is your ‘local’ the Regatta hotel?
Cheers
Mt Tambourine?
Again, thanks for the info and all the best for State of Origin. 😜
I bet Boeing are wishing they had started with a clean sheet of paper rather than the 52 year old Frankenstein that it has become.
Again, thanks for the info and all the best for State of Origin. 😜
I bet Boeing are wishing they had started with a clean sheet of paper rather than the 52 year old Frankenstein that it has become.
BB beats the incompetent third world pilot drum at every opportunity.
If these accidents were the result of mere pilot error, or poor training at one or two airlines, the entire world fleet would not be grounded.
Rather, pilots at the guilty airlines would be grounded until they retrained, while it would be ops normal elsewhere.
That said, I would not fly with Lion Air, but only because of their long history of accidents where the crew clearly were at fault. Others in the know claim that Ethiopian’s standards are actually quite good.
If these accidents were the result of mere pilot error, or poor training at one or two airlines, the entire world fleet would not be grounded.
Rather, pilots at the guilty airlines would be grounded until they retrained, while it would be ops normal elsewhere.
That said, I would not fly with Lion Air, but only because of their long history of accidents where the crew clearly were at fault. Others in the know claim that Ethiopian’s standards are actually quite good.
Is it true that the MCAS fault has manifest itself quite a number of times and been managed successfully by other crews. Obviously MCAS needs to be upgraded, maybe a second channel. I suspect with both the crashes that the A/P was engaged, something I will be looking for in the reports.
Last edited by hoss; 25th Mar 2019 at 05:45.
Originally Posted by Hoss
I suspect with both the crashes that the A/P was engaged, something I will be looking for in the reports.
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Oddly enuf I flew a 0.82 jet for years, no A/T, No protection other than shudder in the airframe (stick shaker but would never trust it) for a stall & somehow we survived, funny about that! Automation brings with it increased risks not less !
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Try telling that to airline CEO’s who espouse that modern jets are so safe that the overpaid bus drivers who operate them are nothing more than button pushers these days on the verge of becoming obsolete.
There is no chance of the world’s pilot demand being satisfied by the traditional slow drip of GA and military pilots. So, the industry has crafted the new legend that low time pilots are entirely as safe and skilled as their rapidly aging senior crew.
Two observations:
1. Modern transport aircraft are an order of magnitude more reliable than prior generations. A young pilot will likely do 3000 hours or so before command, and that will be mostly the same hour 3000 times.
2. The paralysing fear of litigation prevents many airlines from sharing their collective experience in-house. Hence, only a very few lessons are passed on for reflection. The day-to-day “I learned about flying from that” is almost completely lacking. There remains of course rumours and allegations wherever drinks are hoisted, but those are rarely accurate or informative.
I sometimes despair about the state of the industry-while the same reliability that I mentioned above keeps getting better, its not perfect, and can be compromised by management directive. That said, the young people with whom I fly seem earnest and capable. If the manufacturers can once again build an honest aeroplane without eight implied asterisks in every chapter of the FCOM then inexperience may in fact not matter. Except when my family is onboard, of course.
Two observations:
1. Modern transport aircraft are an order of magnitude more reliable than prior generations. A young pilot will likely do 3000 hours or so before command, and that will be mostly the same hour 3000 times.
2. The paralysing fear of litigation prevents many airlines from sharing their collective experience in-house. Hence, only a very few lessons are passed on for reflection. The day-to-day “I learned about flying from that” is almost completely lacking. There remains of course rumours and allegations wherever drinks are hoisted, but those are rarely accurate or informative.
I sometimes despair about the state of the industry-while the same reliability that I mentioned above keeps getting better, its not perfect, and can be compromised by management directive. That said, the young people with whom I fly seem earnest and capable. If the manufacturers can once again build an honest aeroplane without eight implied asterisks in every chapter of the FCOM then inexperience may in fact not matter. Except when my family is onboard, of course.
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GT has been busy solving the ET crash as well.
https://thewest.com.au/opinion/almos...ng-b881131613z
https://thewest.com.au/opinion/almos...ng-b881131613z
https://thewest.com.au/business/avia...ng-b881144100z
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Seems GT is now backtracking in his latest copy and paste attempt at journalism.
https://thewest.com.au/business/avia...ng-b881144100z
https://thewest.com.au/business/avia...ng-b881144100z
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Australia does have a few low-time pilots, but they are typically used as second officers after completing training at a top-flight flying school.
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6. The MCAS operates in slow 9.2 second bursts, then pauses for five seconds, then acts again.
Try hanging by your balls for that long!
I certainly think a B737 trim wheel trimming continuously for 9.2 seconds would get my attention!
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Not only that, as you increase airspeed the nose down effect of the previous controllable mis-trimmed stab that has been ratcheted in overwhelms your physical strength to pitch up due to the airload on the control column. The worst possible thing you could do at that point would be to use the stab trim cutout switches? Why, you now have a severely mis-trimmed stab and no electric trim to recover it quickly, the only way to correct that is through tens-of-turns of the manual trim wheel with you and your mate against a high airload.
I don't think this was a simply or easy scenario to handle.
See my post on this over at R&N Ethiopian thread post #443.
