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To: cymbeline; logi_cal869
I say “autopilot” but it’s called a flight management system now, isn’t it?

Boeing calls theirs "Autopilot Flight Director System (AFDS)"

AFDS is a very complex system. I have found a CBT lesson for 737 NG AFDS. The lesson has 2 parts and is a total of 237 slides. I believe the 737 MAX would have the same AFDS. Here's the links:

Autoflight Part 1

Autoflight Part 2

I’ve read that there’s a switch to disable MCAS. Certainly it’s on the console and labeled.

MCAS cannot be disabled on its own. It is disabled by turning off 2 switches (located on the console) that disable the Speed Trim System (STS).

Wouldn’t you think all pilots would insist on knowing what it does?

The short answer is YES. Please refer to my earlier response #15:

What Boeing should have done

During development and delivery of the 737 MAX Boeing decided that the pilots didn't need to know about MCAS. The 737 MAX had a procedure to handle runaway stab trim. MCAS malfunction would appear to the pilots as runaway stab trim.

That decision is going to cost Boeing a lot of money.

64 posted on 05/22/2019 6:09:08 AM PDT by FtrPilot
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To: FtrPilot

“MAX had a procedure to handle runaway stab trim”

I’m not an expert on piloting or the 737MAX.

Someone told me that with the two planes that crashed, the pilots were going through a step-by-step procedure to handle their situation, but the plane crashed before they got to the step that told them to disable MCAS.

It bothers me that MCAS failed in these two situations because the angle of attack sensor, which is a small airfoil protruding from the fuselage, was damaged, and that these angle of attack sensors are subject to being damaged by something like a bird hitting them.

Particularly bothersome is that Boeing had an extra-cost option to MCAS that would detect a wacky sensor. Very bad PR for this to be an extra cost option.


67 posted on 05/22/2019 7:08:29 AM PDT by cymbeline
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To: FtrPilot

Nicely outlined. But LOL: Really driving home my prior point that autopilot (and manual flight, by consequence) are terms which have no bearing when referencing modern commercial aircraft.

The decision to not include AOA Disagree (an option) on the subject aircraft will also prove to be an expensive mistake. But I’m not sure how much of a difference it would have made under the circumstances.

At a minimum, had the pilots of the (saved) Lion Air flight reported their malfunction, that plane might have been routed for maintenance rather than scheduled the next day for its fatal flight...


76 posted on 05/22/2019 9:07:22 PM PDT by logi_cal869 (-cynicus the "concern troll" a/o 10/03/2018 /!i!! &@$%&*(@ -)
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