MAX’s Return Delayed by FAA Reevaluation of 737 Safety Procedures
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You should only speak for yourself Icarus2001. You may not need to know but many others do need to know this and a lot more before they will trust that the MAX is airworthy under current AD's. Many of us have lost trust in both FAA and Boeing. Trust once lost is very hard to rebuild and rightly so. Perhaps Sky9 is correct. The only successful way forward is to go back to square one and certify as a new type. Some balls ups cannot be fixed except to start again.
Happy to speak for myself, unlike Takwis above who claims "WE NEED to know".
From the tone of your comment and some other posters' it is clear some will NEVER be convinced that the MAX is airworthy again because the same authorities that certified it the first time around are still involved.
From the tone of your comment and some other posters' it is clear some will NEVER be convinced that the MAX is airworthy again because the same authorities that certified it the first time around are still involved.
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While the data may not be public, I'm pretty sure the non-MCAS, high-AOA flight profiles have already been done (and likely redone since the accidents). It was those flight tests that identified the need for something like MCAS in the first place.
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Stick Push and Stick Nudge. Very different animals. Davis insisted upon the Push on T tailed rear-engined aircraft - the Nudge on the 707 etc., and as previously mentioned, the latter didn't require a new type rating.
Stability? I'm not sure we have a clear idea about the no-MCAS handling of the MAX. Not the absolute truth. Recent posts about marked unwanted rotation really shouts a kind of instability, though for the most of the last months it seemed that MCAS 'merely' countered a legally unacceptable lightening of stick forces while approaching the stall, and in very clearly defined configurations/speeds, balanced against long-established rules.
If indeed the bare aircraft - in any configuration - raced into an aerodynamically powered rotation into the stall, I too would be deeply concerned. But, for the last months, it has been strongly implied that MCAS only stops the lightening of control loads?
So the big question has to be, without MCAS, does the aircraft 'flop' nose-up in the late stages of stall entry?
Stability? I'm not sure we have a clear idea about the no-MCAS handling of the MAX. Not the absolute truth. Recent posts about marked unwanted rotation really shouts a kind of instability, though for the most of the last months it seemed that MCAS 'merely' countered a legally unacceptable lightening of stick forces while approaching the stall, and in very clearly defined configurations/speeds, balanced against long-established rules.
If indeed the bare aircraft - in any configuration - raced into an aerodynamically powered rotation into the stall, I too would be deeply concerned. But, for the last months, it has been strongly implied that MCAS only stops the lightening of control loads?
So the big question has to be, without MCAS, does the aircraft 'flop' nose-up in the late stages of stall entry?
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I am not convinced that such flight test data actually exists (yet), since it was sufficient to establish that MCAS was necessary, rather than test high AOA all the way into the stall region.
The skeptical/cynical/paranoid might suggest that Boeing intentionally did not test that part of the flight envelope, since the mere existence of such data would undermine their assertion that the MAX is not fundamentally unstable.
The JATR report may have now forced their hand, like a poker player forced to show their cards.
While the data may not be public, I'm pretty sure the non-MCAS, high-AOA flight profiles have already been done
an excellent screen name for a Boeing apologist
Some posters demanding the release of information, for what? Why are WE entitled to it? We aren't.
Regulators have grounded the aircraft. It will get sorted out. If you don't like the result, well you can choose to vote with your feet, either as a pilot on a max or as a passenger.
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While I understand your point to some extent, I believe you are grossly underrating the breach of trust resulting from the actions of both Boeing management and the FAA. Take statements from well seasoned jet professionals, e.g. Sully. People are angry, and rightly so. Boeing as well as FAA must re-earn that trust, and what would be better than complete transparency? What would be the argument to not publish essential airframe stability data? It is supposed to become a public transport vehicle, after all. And all will be subject to public court proceedings, anyway... So this is not about whether to publish, but when. ASAP would be my advice, to reduce the baying for Boeing blood...
Aerodynamically, MAX doesn't meet certification stability criteria.
MAX can't be fitted with certified stability augmentation and stall avoidance systems as it would invalidate grandfather rights and as a new design it just would not comply with the current rules even if pitch stability were not an issue.
The only way MAX will ever fly again is by severe reduction of certification requirements so the Boeing management's policy of admitting nothing and waiting for Deus ex machina rescue is quite sound.
A simple check of your log book would prove your "every day" statement incorrect.
I will remind you that there have been many extremely informative posts on this thread, made by persons that certainly are not "Jet Transport /Airline Aircraft Pilots"
Big watches was a 90's thing.
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Exactly and why would they be public?
Clearly nuance and subtlety is not your strong point. I am in no way an apologist for anyone but the group think going on in here baying for Boeing blood is way over the top.
Some posters demanding the release of information, for what? Why are WE entitled to it? We aren't.
Regulators have grounded the aircraft. It will get sorted out. If you don't like the result, well you can choose to vote with your feet, either as a pilot on a max or as a passenger.
Clearly nuance and subtlety is not your strong point. I am in no way an apologist for anyone but the group think going on in here baying for Boeing blood is way over the top.
Some posters demanding the release of information, for what? Why are WE entitled to it? We aren't.
Regulators have grounded the aircraft. It will get sorted out. If you don't like the result, well you can choose to vote with your feet, either as a pilot on a max or as a passenger.
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Boeing on using redundancy to the max
“It’s too early to determine why all three main parachutes did not deploy, however, having two of three deploy successfully is acceptable for the test parameters and crew safety,” Boeing said in a statement.
Show us the data
We should be reasonably confident that ‘the data’ exists, but less so in the way it was interpreted and applied in design and certification.
For those who wish to see the data; you are given it - then what. You make your own (non-expert) interpretation, judging safety in whichever way you choose.
The underlying issue is trust, restoring confidence in the regulator and manufacturer which certificated previous (subsequent) types.
Neither the FAA or Boeing have excelled with their attempts to restore confidence, particularly with the lack of information. This may be the greater task in returning the Max to (profitable) service than the technical problems - technicalities can be fixed, issues of trust confidence might only be restored slowly, and never to previous levels. Also technical problems relate to knowledgable people in the industry; with trust, sentiment, the general public, may not be so easy to convince.
What the industry requires are clear technical descriptions of what MCAS was supposed to do, why, and how. Then as appropriate, how the proposals will address the shortfall in operation; the why and how.
Operators need the technical descriptions, piloting and engineering, which were absent in the original Max documentation.
For those who wish to see the data; you are given it - then what. You make your own (non-expert) interpretation, judging safety in whichever way you choose.
The underlying issue is trust, restoring confidence in the regulator and manufacturer which certificated previous (subsequent) types.
Neither the FAA or Boeing have excelled with their attempts to restore confidence, particularly with the lack of information. This may be the greater task in returning the Max to (profitable) service than the technical problems - technicalities can be fixed, issues of trust confidence might only be restored slowly, and never to previous levels. Also technical problems relate to knowledgable people in the industry; with trust, sentiment, the general public, may not be so easy to convince.
What the industry requires are clear technical descriptions of what MCAS was supposed to do, why, and how. Then as appropriate, how the proposals will address the shortfall in operation; the why and how.
Operators need the technical descriptions, piloting and engineering, which were absent in the original Max documentation.
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Am I going to analyze the data myself, as someone suggested? No, I have neither the skills, nor the time for that. I have suggested, in the quote above, a body willing, able, and that has signaled a desire to do it. Has the data been gathered and analyzed before, of course it has. But those who did so have decided not to make it public...in fact kept their attempt to correct those flight characteristics secret as well, until people started dying. So, we need to rely on someone who is going to be honest and open.
Latest from EASA
A good update; more technical information from EASA @ https://aviationweek.com/commercial-...02a94c54606e9b
Worth the hassle of registering if not already open.
Details of bilateral certification agreement. FAA did not highlight MCAS to EASA as a significant change.
Testing complete this month, certification approval in Jan, but more open-ended about training, simulators, overflights, and other regulators.
Third AoA vane sensor unlikely, but a synthetic third input likely with software changes, separating computation and monitoring.
Wise and guarded views on relationships between FAA - EASA and FAA - Boeing, grandfather rights, crew workload, pilot training and experience. (Ref to ‘average’ pilot probably for public, not certification use.)
Worth the hassle of registering if not already open.
Details of bilateral certification agreement. FAA did not highlight MCAS to EASA as a significant change.
Testing complete this month, certification approval in Jan, but more open-ended about training, simulators, overflights, and other regulators.
Third AoA vane sensor unlikely, but a synthetic third input likely with software changes, separating computation and monitoring.
Wise and guarded views on relationships between FAA - EASA and FAA - Boeing, grandfather rights, crew workload, pilot training and experience. (Ref to ‘average’ pilot probably for public, not certification use.)
