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Comment by msbarnett | Hacker News Reader

Nope.

The Boeing/FAA directive re: MCAS does not instruct them to extend flaps.

Further, there's other things going on in the cockpit due to the malfunctioning AoA sensor that's the root of all this.

Specifically one of the effects is that they get an Unreliable Airspeed Indication, and run that checklist. That checklists memory items include maintaining the current flap configuration (in this case, flaps up).

The Boeing/FAA directive does not instruct them to deviate from this and extend flaps. They have a checklist memory item instructing them to in fact do the exact opposite, and not touch flaps.

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You're correct that the AD and runaway trim procedure does not instruct them to extend flaps. What I was addressing was the statement upthread that "Flaps out supposedly would have kept MCAS off but the pilots weren't expected to know that."

If I'm a 737 MAX pilot, after the Lion Air crash I'm learning absolutely everything I can about MCAS. And from information Boeing provided I would learn that it operates with autopilot off, flaps up, at high indicated AoA.

You mention unreliable airspeed, that was actually their first problem. Flaps were extended at that point, as according to the narrative they were not retracted until after the AoA disagree, stick shaker, and airspeed disagree. In fact it almost reads like they were intending to continue the flight, engage autopilot, and climb to 32,000 ft with the stick shaker going the whole time. That seems very odd to me.

>If I'm a 737 MAX pilot, after the Lion Air crash I'm learning absolutely everything I can about MCAS. And from information Boeing provided I would learn that it operates with autopilot off, flaps up, at high indicated AoA.

And in a crisis situation you skip the checklists and think fast and apply your instincts because you read something on a forum? Sure if you have a lot of time you can try thinking but this is not debugging a bug where you have hours to observe the issue, try different inputs, observe again, Google some questions etc..

We don't want pilots to be creative. Air safety is so good because pilots learn memory items and checklists and actually follow them instead of making stuff up.

If the checklist doesn't mention flaps and the plane crashes if you keep the flaps up, that's on Boeing.

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