Posted on 05/03/2019 8:50:09 AM PDT by billorites
Boeing limited the role of its own pilots in the final stages of developing the 737 MAX flight-control system implicated in two fatal crashes, departing from a longstanding practice of seeking their detailed input, people familiar with the matter said.
As a result, Boeing test pilots and senior pilots involved in the MAXs development didnt receive detailed briefings about how fast or steeply the automated system known as MCAS could push down a planes nose, these people said. Nor were they informed that the system relied on a single sensorrather than twoto verify the accuracy of incoming data about the angle of a planes nose, they added.
Investigators have linked faulty sensor data to the flight-control systems misfire, which led to crashes in Indonesia and Ethiopia that took 346 lives. Share Your Thoughts
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The extent of pilots lack of involvement hasnt been previously reported and could bring fresh scrutiny from investigators and regulators already looking into Boeings design and engineering practices. It isnt clear whether greater pilot participation would have altered the ultimate design of the flight-control system. But the scaling back of pilots involvement and their lack of detailed knowledge about the planes system add to the list of questions about engineering and design practices facing the Chicago-based aerospace giant.
A Boeing spokesman said test pilots and senior pilots didnt have less of a role in the design, briefing and testing of the final version of MCAS when compared with counterparts who worked on previous models featuring important new systems.
Listening to pilots is an important aspect of our work, the spokesman said. Their experienced input is front and center in our mind when we develop airplanes. We share a common prioritysafetyand we listen to them carefully.
(Excerpt) Read more at wsj.com ...
Did this stuff happen when Alan Mulally was there. I followed the design and testing of the 777 under Mulally. It was mindbogglingly severe. Then Ford coaxed him away from Boeing and he pulled Ford’s chestnuts out of the fire when the automobile industry was sliding into the toilet.
Many single engine fighters are inherently unstable.
They have ejection seats.
That seems odd, since on takeoff the upward angle would necessarily be great to get altitude, and if he MCAS is to prevent to much of a vertical inclination that is when you would need it.
So when would it engage? - Tom
“It was designed to over ride pilot input during high g steep turns when continued input would put plane out of posting envelope.
DEACTIVATED when flaps not restricted.
Only became activated in crashes when flaps were retacted.
” Furthermore, FAA should never have certified a craft that was inherently unstable.”
NOT INHERENTLY UNSTABLE.
You are 100% right and completely justified in your anger.
Both the FAA and BA are culpable, but neither will suffer for their transgressions. It will simply not be allowed.
Lie #1. The 737-8 MAX is NOT unstable in pitch around the lateral axis when flown at high angles of attack and under conditions of high thrust. It reacts differently, but no unsafely, from the previous 737-800 NG under those circumstances. MCAS was designed to allow the pilot to experience the same handling in the MAX as in the NG, thus preventing the need for a new type rating. It was not designed to correct a dangerously unstable condition.
Rather than address the underlying aeronautical design flaws, ...
Lie #2. There are no aeronautical design flaws, and the design is not inherently unstable at high AoA. Without MCAS, the MAX behaves differently from the NG or the Classic, but not unsafely so.
... and risk certification as a 737 variant, a decision was made to fix the problem with a "software kludge" the MCAS system.
You are correct when you cite the reason for MCAS was to maintain type certification, but MCAS was not a kludge. It is also used on the KC-46A tanker. Were MCAS a 'kludge', it would not have been used on a new military aircraft.
And understand that when we talk about "certification," we are talking about the pilot's type certification, not the aircraft's airworthiness certification. Commercial pilots are only allowed to be current on one aircraft type, so if Boeing could not have the MAX covered under the 737 NG pilot type certification, then you would need to have one group of pilots that could only fly Classics and NGs, and another pool of pilots that could only fly the MAX. Not an ideal situation for airlines, which is why Boeing went to such lengths to avoid a separate type certification for the MAX.
Now, if you wish to slander Boeing, you have plenty of ammunition to do so. Boeing claimed that MCAS would rarely, if ever, be experienced by pilots because of the very narrow and specific conditions that had to be met before MCAS even came into play. The aircraft must have flaps up, be in a steep climb, not be in autopilot, and must be below certain airspeeds based on AoA.
Because of these narrow conditions where MCAS would be operational, Boeing's engineers failed to appreciate the effects of a failed AoA sensor would have on the aircraft, and failed to adequately protect for it.
Had they done so, Boeing would have made the cross-checking of the AoA sensors a mandatory part of the MCAS routines at all times, as they now are doing as part of the effort to return the MAX to service.
Instead, Boeing only initially put AoA sensor cross checking into those aircraft that optionally purchased the display of AoA to the pilots on the flight display. Boeing knew that if it were displaying information to the pilot, it had to be reliable information. If AoA was not presented to the pilot, then Boeing incorrectly assumed that the cross check of the two AoA sensors was unnecessary. Neither the Lion Air nor the Ethiopian had the option to display angle of attack on the flight displays, so they were not equipped to cross-check the two AoA sensors. It simply alternated which AoA sensor was used for MCAS every other flight.
However, when you state that Boeing intentionally manufactured an inherently flawed, unstable design and attempted to correct it with a hastily-designed software patch, you demonstrate that you have read a little of what other hacks have written about the MAX and are parroting those talking points, but you have no real knowledge of the situation, and perhaps shouldn't be pontificating on subjects you do not fully understand.
If you are interested in learning the facts, not the sensationalized news accounts written by poorly-informed reporters, you might want to start your education here:
I completely agree with you. There’s no way this made it through engineering without concerns. There has to be an email chain. When it comes to safety software we talk about “lazy, ignorant, or incompetent”. If one or more can be shown then you’re liable. In this case, I’ll bet it was none - things were done very consciously, which imo, makes this criminal - especially after the first crash, they’d already been working on a software update but never grounded the planes.
They weren’t lazy, I bet management just overrode engineering, they weren’t ignorant about safety engineering concepts, and they weren’t incompetent - again, go to the engineering emails.
To me this is criminal, hundreds needlessly died. They should have grounded the planes. Somebody needs to go to prison.
I'm not sure where you read that, but in Boeing (unlike Airbus) the control columns are connected by a torque tube (which apparently was broken in the Atlas 767 crash). Although there is a stick shaker on each control column, "either stick shaker vibrates both column through column interconnect." (from 737 flight manual). I'm not sure in the heat of the battle it would be easy to figure out which shaker was going off.
Also since there is an interconnect, it doesn't really matter which seat the flying pilot is sitting in, column input from either seat affect the airplane the same.
And transferring controls in the middle of an emergency is not standard, not trained and could create more confusion than it helps.
I am suspecting that the Max fleet will never fly again. I also suspect that Boeing is going to end up having to buy them all back.
Dang. Only can be active when flaps fully retracted.
Are you willing to wager $100 to the Free Republic Fundraiser that the 737-8 MAX will be back in regular airline service by December 2019?
If the MAX goes back into service before December 2019, you pay Jim Robinson $100 to the Freeper Marathon. If by December 31, 2019, the MAX is still grounded, I will pay $100 to the Freeper Fundraising Marathon.
Deal?
You can find the information here:
https://leehamnews.com/wp-content/uploads/2019/04/Preliminary-Report-B737-800MAX-ET-AVJ.pdf
The captain should have transferred control to the first officer, because the stick shaker going off on one side indicates a bad sensor on that side and the instruments may not be reliable on that side.
Why didn’t the pilots diagnose why the stick shaker was going off?
It wasn’t an emergency at that point, so that’s not an excuse.
It's amazing what big corporations which own friends in DC can absorb. I wonder if Boeing will be bailed out in the national interest, and execs and those responsible will still get their obscene salaries and compensation.
It worked out that way after really bad banking nearly sank the economy.
Or the GM/Chrysler bailout, although Chrysler paid back their deby.
How about we just say a drop dead date of December 31, 2019?
If the planes are back in service by that date I’ll happily pay $100 to FR.
If they aren’t then you pay.
Fair enough? If so, we’re on.
Megan
Deal. Either way, JimRob wins. But if I were you I’d start saving my pennies. I think the MAX will be back in service by the end of July.
“Why didnt the pilots diagnose why the stick shaker was going off?”
They went to cutout on the trim power indicating some awareness of the problem.
Apparently turned it back on after trying to trim manually.
We will see, won’t we?
They went to cutout on the trim power indicating some awareness of the problem.
...
They did that because of the runaway trim. It was one of the few things they did right. But they should have used the electronic trim switch on the control wheel to neutralize the trim before cutting off the trim power.
They never did diagnose why the stick shaker was going off.
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