Questions tagged [mcas]
For questions related to Boeing's Maneuvering Characteristics Augmentation System (MCAS).
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Could the pilots really not trim manually to overcome MCAS, as shown in the Netflix Downfall documentary?
In the recent Netflix documentary, a claim is made that once MCAS activated, after several activations, the pilots physically could not trim the aircraft due to the speed and pitch.
Is this true? I ...
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Would fitting a T-tail on the 737 Max make MCAS unnecessary?
This is pretty far out, so I just pose it as a question for notion or ideas, rather than conclusive answers.
Considering the differences in flight characteristics between the Boeing 737 Max-8 and ...
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What is MCAS' purpose? [duplicate]
In a recent question, one of the answers states:
MCAS has nothing whatsoever to do with stall recovery or stall behaviour.
It was implemented strictly to make the MAX's pitch stick force response in ...
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I have an idea about how to resolve a conflict between the pilots and an automated flight control system. Does it make sense? [closed]
I am thinking about the 737-MAX crashes. There is a similar question at Is it common for automated control systems to use non-redundant sensors? There was an article in yesterday's Seattle Times In ...
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What programming language(s) is Boeing's MCAS written in?
What language is Boeing's MCAS written in?
Thanks
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On the 737 MAX, can the pilots switch to the backup MCAS, or switch active MCAS input to another AoA probe during flight?
According to this article, my assumptions about the Boeing 737 MAX flight control system are (please correct me if I am wrong):
The aircraft has two flight control computers (FCC)
The aircraft has ...
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Why does the KC-46 use two sensors for MCAS when the 737 Max doesn’t?
this article states
The KC-46 has a two-sensor MCAS system, which “compares the two readings,” the Air Force said.
I’m aware that the 737 uses two sensors and always has, but the computer reads ...
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How does MCAS communicate with other systems to know if the flaps are retracted or not?
How exactly does MCAS communicate with the flaps setting to know if the flaps have been retracted?
I just noticed on the preliminary report for ET302, the flaps were set at 5 degrees. It doesn’t say ...
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Did Boeing need MCAS because the 737 MAX didn’t meet FAA longitudinal stability requirements, or was it to make the MAX feel like the NG?
I’m confused on this. I’ve read in multiple different places that
MCAS was required due to the easier stick forces at a high angle of attack and a high G force, and because of this, the Max didn’t ...
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Will the 737 Max 10 have MCAS?
With the fuselage plugs forward of the wing, would this mean the engines are closer to CG, therefore no need for MCAS?
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Why does the KC-46 use an MCAS?
The KC-46 tanker aircraft (the U.S. military's designation for the 767s it uses as tankers, and which every other country calls the KC-767) uses an early version of an MCAS.1 This was ostensibly ...
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Why does the MCAS use the horizontal stabiliser rather than the elevators?
The Maneuvering Characteristics Augmentation System (MCAS), found, in two slightly-different variants, on the 737 MAX and KC-46, provides nose-down pitch inputs in certain very-high-angle-of-attack ...
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Why couldn’t Boeing just use the stab trim system to do MCAS job?
If I’m incorrect in the question, please correct me. From what I’ve read and gathered the stab trim system essentially did the same before hand? It relies on AoA? And if so, did the computer for that ...
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Was MCAS part of 737 8 MAX MMEL list?
I think the answer to this question is no, because I cannot find it in the PDF, but I'd like a more expert opinion.
The reason I'm asking is the assumption that if it was, its malfunction could have ...
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How the stabilizer cutout switch functionality has changed from Boeing 737 NG to 737 MAX?
The Boeing 737 NG has stabilizer trim cutout switches marked as MAIN ELECT (left) and AUTOPILOT (right). Turning off the right switch disables automatic stabilizer trim in autopilot mode and automatic ...
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Does the a320 neo have anything like MCAS? [duplicate]
I am trying to book a flight that will be on an A320 NEO.
Does this have any 'new' systems or features, like the MAX MCAS system?
I'm asking this question also because one airline has just grounded ...
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Why the need for the MCAS on the Boeing 737 Max 8? [duplicate]
Was there a problem with stalling on 737 jets before the 737 Max, if not then why is MCAS needed on the 737 Max 8.If it was a problem why did Boeing wait so long.
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How does MCAS compare to stall protection systems installed in other aircraft? [closed]
How is MCAS in 737 MAX 8 different from the stick pusher in MD80 or DHC8 and from the Airbus alpha protection, in terms of overall safety?
All these systems will push the nose down at high AoA and ...
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How does engine geometry affect flight stability?
News items around the recent aviation accidents involving Boing 737 MAX 8 aircraft suggest, that bigger engine diameter demanded for a different (longer) nacelle strut for proper ground clearance ...
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Why would Boeing's MCAS be preferable to a modified Feel and Centering Unit?
According to some sources, the purpose of MCAS on Boeing's 737 MAX variants is to increase the back-force needed to further raise the nose when flying manually at high angles of attack, in order to ...
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Can airlines choose whether or not to enable MCAS on their fleets, and if so, have US airlines chosen to do so?
I've been told that, although all 737 Max aircraft are equipped with MCAS, the system can be deactivated by the individual airline. I've also heard that US airlines never activated MCAS in their 737 ...
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Did A320 NEO need an equivalent to 737 MAX MCAS because of its bigger engines?
We read that MCAS on the Boeing 737 MAX was needed because of the new, bigger, heavier engines of the MAX compared to the previous 737 versions.
The closest equivalent to MCAS on the Airbus A320 NEO ...
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If the updated MCAS software needs two AOA sensors, doesn't that introduce a new single point of failure?
Regarding the 737 MAX story, the New York Times writes:
"Boeing’s software update would require the system to rely on two
sensors, rather than just one, and would not be triggered if the
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Has the Boeing 737 MAX MCAS system successfully prevented a stall or approach to stall condition outside testing?
The Boeing 737 MAX MCAS system has been in the press a lot as it has been implicated as a possible cause of 2 fatal crashes. The MCAS system was put in to prevent a wing stall caused by excessive ...
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Boeing Dreamliner MCAS [closed]
If it was not known that Boeing had new software in the Boeing 737 Max, do we know whether this same software is not in the 787-9?
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what type of sensors does the Boeing 737 MAX use for MCAS?
I can imagine there are several different ways to measure angle of attack (accelerometers, relative pressure measurements between pitot tubes, etc), but I'm curious which sensors the 737 MAX uses for ...
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Is the Boeing 737 MAX 8 MCAS exceptional in operating when autopilot is off?
To the uneducated reader it seems strange the Boeing 737 MAX 8 MCAS system only operates when autopilot is off. I understand the reasoning behind why it was implemented to operate when autopilot is ...
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What is the technique or procedure to disable/disengage the MCAS on Boeing 737 Max 8 & 9 Aircraft?
What is the technique or procedure to disable the MCAS and manually fly the Boeing 737 MAX 8/9 Aircraft?
To clarify my question, what I'm asking is can the pilot disengage the MCAS and if so, how do ...
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Can computer imposed inputs be overridden on the Boeing 737-MAX?
During Lion Air Flight 610, a Boeing 737-MAX, it seems that the angle of attack sensors caused the software to believe the aircraft was stalling, thus initiating a nose-down pitch to recover from the (...
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