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Old 10th Mar 2019, 22:43
  #196 (permalink)  
gums
 
Join Date: Jun 2009
Location: florida
Age: 81
Posts: 1,610
Received 55 Likes on 16 Posts
Salute!

@Nieuport28, fsfaludi & silverstrata
Right on!

@klintE
Honestly, I think you, klintE are wrong.

As prolly the oldest pure FBW pilot here ( unless you were a Concorde dude or flew a test plane back in 1979), I wanna clear up the gross misunderstanding about FBW that many folks still have and exhibit.
And correction for aerodynamics in software is mandatory
No so. You can have a perfectly good B-17 and simply replace all the cables and such to each control surface, and maybe the horizontal stab with a single hydraulic line and a hydraulic actuator commanded by some wires. This is opposed to the original irreversible hydraulic flight control systems we saw in the 50's and later in most of the "fast jets" ( as the Brits say). No direct feedback but a few attempts to help. In other words, no ropes, pulleys, tubes, cables, etc.
Although you can use the FBW implementation for better stability, stall prevention and gee limits and ..... that's not the sole reason for FBW. And the new F-35 doesn't even have hydraulic lines to the surface actuators - they are electrically driven, local hydraulic or electric actuators. They are truly "electric jets", even tho we called my old Viper the original "electric jet"..

The B-2 FBW system did, indeed, command a bad pitch after WoW due to sensor contamination by water. Simple maintenance procedures and crew actions prevented future occurences.
The AF447 FBW system did not fail due a bad sensor. It commanded pitch trim so the pilot would not have to keep holding back stick, which he did for a long time, even after the other guy said they were climbing.

Lastly, there's at least one flight control surface on the 737 that is FBW.

Let's face it, the new mod to the very old plane that was certified 50 years ago would not have been certified back then. I have looked closely at the U.S. Part 25 requirements for trim, stall conditions, etc and I have a hard time believing the MAX version was certified.

Gums opines...
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