My E145 uses the AE3007 engine (a variant of which is used on the Citation X), and the response to lever movement is almost immediate. Would I be correct in assuming that it's less prone to thermal choking because of a more advanced design of the compressor/burner sections?
The way I understand it, it's both the surge margin
AND spool innertia, that play part:
- the surge margin (as explained so neatly in previous posts) limits the excess power that can be used to accelerate the engine
- with the limited excess power available, it takes more time to accelerate a bigger fan than a smaller one.
I guess you can improve the former a bit by designing a more advanced compressor, but there's not much to be done about the latter, especially if efficiency dictates designing a small core/large fan combination.
Because of relatively small fan in your Allison engine, the core has an easier task of accelerating the fan, than in a GEnx...