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To: Yo-Yo
Stop spreading lies.

What is your argument? "Stop spreading lies??" That's it?? Don't be an asshole.

36 posted on 05/03/2019 10:07:31 AM PDT by rexthecat
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To: rexthecat
The redesign of the 737-800 Max resulted in an aircraft that was unstable in pitch around the lateral axis when flown at high angles of attack and under conditions of high thrust.

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:

http://www.b737.org.uk/mcas.htm

47 posted on 05/03/2019 11:21:32 AM PDT by Yo-Yo ( is the /sarc tag really necessary?)
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