Originally Posted by
Pilot DAR
... But when doing that pushes the thinking of aircraft certification ...
That's exactly what is being asked by the authorities. As well as a strive for efficiency, the push to an ETR is environmental. It can make an impact on the noise footprint, critical in approving modern air operations.
There are already electric motors and actuators on the critical parts list, you can't choose to ignore all the FBW advancements and the lessons learned. We know how to design, build and certify using redundant feeds and multiple wingdings isolated electrically and thermally. It is not a big step in to the unknown ... not saying it is cheap, but if the regulations allow for a competitive advantage to be gained then the business case will follow. I am most definitely not advocating using RPM alone or stopping the TR in flight. But changing RPM allows optimisation to particular phases of flight.
Thanks for sharing the weight estimate. I came up with a similar %delta for the ETR. The motor about 25kg, the feeds another 10kg and the generator 40kg. So 75kg replacing about 65kg. So a weight gain, but I am convinced that the MGB could be further simplified and you have greater choice over where the generator is placed.