Originally Posted by
GordonR_Cape
I previously asked the question: How could the autopilot ever get into a high AOA situation? One answer was if the autothrottle is disabled. The implication being that the autopilot could keep increasing the nose up pitch until the stall warning activates, and the crew intervenes. I hope that scenario has been carefully tested?
In the 737 as well as every other aircraft I have flown, the autopilot will attempt to do exactly what you told it do - until it can’t. It then disconnects with whatever alerts that it provides at whatever trim state and power settings were in place. This will often result in the pilots suddenly having to take command of an aircraft that is in, to use the popular euphemism, an “undesired aircraft state.” This can potentially be a very shocking moment.
Even when the autopilot is in use, at least one of the pilots is expected to actively monitor the aircraft. If the autopilot is struggling, then there will be signs depending on what exactly the problem is. The pilot is then expected to intervene and correct the problem. Until the technology progresses to a point that this active monitoring role is no longer needed, this is not a “design” issue, it is a pilot training issue.