Re: [OT] “Raise the nose, HAL.” “I’m sorry, Dave, I’m afraid I can’t do that.”

[Walter Bright]

On 4/23/2019 1:09 AM, Russel Winder wrote:
> The 737 MAX is, as far as I know, the first commercial airplane to be
> unstable.

They are all unstable in certain parts of the flight envelope. All swept wing 
airplanes are unstable.

https://en.wikipedia.org/wiki/Dutch_roll

All jetliners are augmented with a yaw damper.

There are other automatic systems in a jetliner to prevent the pilot from doing 
something stupid. For example, the faster the jet goes, the less authority the 
pilot has over the elevators. This is to prevent the pilot from literally 
ripping off the elevators. I'm not sure, but I think this device is controlled 
electronically.

The airplane will also become uncontrollable if you fly it too fast, like in a 
dive. Yes, this has happened, sometimes due to other factors, sometimes because 
the pilot wasn't paying attention.

All airplanes have a "flight envelope" that pilots had better stay inside of or 
they're gonna crash. The MCAS system was put in to prevent one bad part of the 
envelope from being accidentally entered. It is not near part of the normal 
flight envelope, likely why pilots had never encountered MCAS activation before.