787 flaperon behaviour on takeoff roll

[megan]

Modal suppression, likewise on the 787-10

https://www.federalregister.gov/docu...y-requirements

An extensive discussion on the subject.

https://arc.aiaa.org/doi/10.2514/1.C034442

[Neektu]

Originally Posted by megan

Modal suppression, likewise on the 787-10

https://www.federalregister.gov/docu...y-requirements

An extensive discussion on the subject.

https://arc.aiaa.org/doi/10.2514/1.C034442

Thank you. I’ve been looking for extra information on those features.

[Vessbot]

Originally Posted by Uplinker

Likewise.

A few seem concerned about having autonomous flight control surfaces, but have pilots ever been concerned about the yaw damper fitted to the aircraft they fly? The yaw damper is automatic and transparent to the pilots. It just works.

Any system should be properly developed, test-flown, and engineered. If a system has NOT been properly developed, test-flown and engineered - for example the Boeing MCAS - problems can arise.
.

I see the similarity, but yaw dampers are standard jet equipment, with a well-understood reason for existence since the 50's. I think recent history justifies a raised eyebrow at other self-moving control surfaces that Boeing slipped under the rug and ran.

[Uplinker]

Yes, fair comment.

One would hope this system is fail-safe, unlike the MCAS.

[tdracer]

Originally Posted by Uplinker

Yes, fair comment.

One would hope this system is fail-safe, unlike the MCAS.

FBW is a flight critical system - Design Assurance Level A (DAL A) - and is developed and certified accordingly.
The problem with MCAS is that it wasn't considered to be a flight critical system - it was assumed to be a 'major' system, and developed and certified accordingly. Had MCAS been recognized as a flight critical system it would never have been implemented the way it was.

[Check Airman]

Originally Posted by tdracer

FBW is a flight critical system - Design Assurance Level A (DAL A) - and is developed and certified accordingly.
The problem with MCAS is that it wasn't considered to be a flight critical system - it was assumed to be a 'major' system, and developed and certified accordingly. Had MCAS been recognized as a flight critical system it would never have been implemented the way it was.

Hindsight is indeed 20/20.