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

[Uknown]

On Tuesday, 23 April 2019 at 08:09:58 UTC, Russel Winder wrote:
> On Mon, 2019-04-22 at 13:35 -0700, Walter Bright via 
> Digitalmars-d wrote: […]
>> [snip]
> Surely, Boeing need to remove the MCAS system by reverting the 
> 737 design to be stable rather than unstable.
>
> The 737 MAX is, as far as I know, the first commercial airplane 
> to be unstable.

The McDonal Douglass MD-11 was also unstable and was used for 
freight transport.

Wiki link : https://en.wikipedia.org/wiki/McDonnell_Douglas_MD-11

It was designed to have a smaller stabiliser, to reduce drag and 
thus improve fuel efficiency.

> All military fighter airplanes are unstable but that is a 
> military fighter. To date, again as far as I know, the strategy 
> had been that all commercial aircraft were stable. Boeing broke 
> ranks on this strategy with the 737MAX simply because they were 
> trying to put an engine that was too big for the space 
> available and so moved the engine forward and upward creating 
> an aerodynamically unstable configuration.

Not all are, the ones that are unstable are generally designed in 
that way so that they are more manoeuvrable. They use use digital 
fly by wire to make sure that the plane is seemingly stable. This 
decision by Boeing would have been fine if they had designed 
their software properly.