The fact that "AoA disagree" light and logic was an optional feature seems criminal enough to me. A sensor with no failover unless you pay for an option. Who the hell thought this was a good idea or approved it? WTF!
500 people are already dead. Boeing should be brought to the coals. It probably takes longer to go through the checklist than it does for everyone to die.
I promise if the audio recordings are ever released from CVR they will be absolutely damning. Pilots trying to make it through a loss of control checklist as they dive to their doom. A lot of those checklists have 50+ steps. Imagine trying to make it through that while fighting the plane and descending at over 3x "maximum design descent rate".
I'm sure the fucking alarms we're blaring and pilots cursing the system carrying them toward certain death.
The checklist in question has three steps. Step two is "move stab trim to cutout," which disables automatic systems that adjust the stabilizer. The pilots in lion air had ~10 minutes to do this.
It is extremely unlikely that the pilots were trying to work through the checklist. More likely they simply did not know what to do.
This one's actually a memory item, not a checklist. But it's the memory item for "runaway trim", which is a very different qualitative experience than the slow march of an MCAS system that you didn't know existed.
This doesn't make jive with disaster being averted by a third pilot. Assuming the third was totally dedicated to checklist vs preventing the plane from diving, it was only his insight that stopped the plane from going down.
The MCAS system apparently increased downward trim without any speed considerations, to over 2.5 degrees in 10 seconds. I don't have the full flight control details but it sure sounds like pilots would lose control within minutes at most. In the LionAir crash the pilot reported control problems and asked to return to airport within 3 minutes, and they slammed into the ocean in 12.
Not sure where you're getting this info but I'm more than sure they knew something was wrong in the last 2 minutes (while they were heading into the earth at almost the speed of sound).
You really think they have ten minutes to react when by then everyone on LionAir was doomed to die?
This "human" factor was also characterized in the movie Sully when it was apparent that just a few extra seconds for pilots to process the issue made all the difference between landing safely at a nearby airport vs. landing in the Hudson River.
Engineers don't make decisions like this. Not providing documentation of the feature or providing training to pilots was the problem, and it's caused by multiple management failures. The lack of sensor redundancy likely also is due to management.
The lack of sensor redundancy HAD to be signed off by a professional engineer. It doesn't matter if management pushed it; it's the engineer's (PE's) responsibility to refuse to sign off on it.
I’m not convinced sensor redundancy is the issue. The plane has two sensors; for some reason, however, the package that includes the AoA disagreement light costs extra.
It seems that lack of training and documentation was the reason these planes crashed though. The pilots didn’t know how to recognize the issue or resolve it.
500 people are already dead. Boeing should be brought to the coals. It probably takes longer to go through the checklist than it does for everyone to die.
I promise if the audio recordings are ever released from CVR they will be absolutely damning. Pilots trying to make it through a loss of control checklist as they dive to their doom. A lot of those checklists have 50+ steps. Imagine trying to make it through that while fighting the plane and descending at over 3x "maximum design descent rate".
I'm sure the fucking alarms we're blaring and pilots cursing the system carrying them toward certain death.