31–40 of 269 posts
Earlier quoted context omitted.
Do we know if the issue is bad software or bad specs? Even formal methods won't save you from a bad spec.
I don't think we've seen anything to indicate that the problem is not a bad spec.
So a single point of failure (malfunctioning sensor) can engage the horizontal stabilizer without notifying pilots, in a way that the control yoke can't override. What the hell did Boeing think was going to happen?
I think Boeing has handled the aftermath (and much of the lead up since the release of the plane) very, very poorly. I, as a layman to aviation, am not willing to bet that Boeing knew the true likelihood of a problem and didn't tell anyone or had a whistle blower over it.
However, if the issue with a non-redundant hydraulic value in the original 737 didn't teach us the lesson, this should: no matter the likelihood of failure, safety critical systems should always be redundant.
(Also, Boeing didn't handle that original issue very well either.)
Is it possible for Boeing engineers to lose their professional status as a result of this situation?
It lies with the managers who wrote the specification that said that for business reasons the new plane must not require any additional training or type certifications, and cut costs by implementing the required systems with a non-redundant sensor.
> [T]hey got help from an unexpected source: an off-duty pilot who happened to be riding in the cockpit. That extra pilot, who was seated in the cockpit jumpseat [...] Am I missing something here? Isn't it normal for off-duty pilots to ride in the jump-seat?
Downvote away...
Runaway trim is supposed to be part of the "memory checklist" for pilots. The symptoms of MCAS are the same as runaway trim and the fix is the same (which is why Boeing didn't feel like extra pilot training was needed), so I'm curious to see the most recent investigation and hear the black box voice recorder. Did they not know they were dealing with runaway trim? Did they think it was something else? Did they forget…
Is it possible for Boeing engineers to lose their professional status as a result of this situation?
The fault doesn't lie with the engineers who built the system...not to mention I would be very surprised if they were professionally certified. It lies with the managers who wrote the specification that said that for business reasons the new plane must not require any additional training or type certifications, and cut costs by implementing the required systems with a non-redundant sensor.
So a single point of failure (malfunctioning sensor) can engage the horizontal stabilizer without notifying pilots, in a way that the control yoke can't override. What the hell did Boeing think was going to happen?
Runaway trim is supposed to be part of the "memory checklist" for pilots. The symptoms of MCAS are the same as runaway trim and the fix is the same (which is why Boeing didn't feel like extra pilot training was needed), so I'm curious to see the most recent investigation and hear the black box voice recorder. Did they not know they were dealing with runaway trim? Did they think it was something else? Did they forget…