The latest generation of very high bypass engines (such as the GEnx) are very lazy off of minimum ground idle. Tiny core, really big fan - it takes a while to get that fan spinning.
Thanks. That makes sense...
Because of relatively small fan in your Allison engine, the core has an easier task of accelerating the fan, than in a GEnx...
As does this. I kind of figured the big fan would take longer to accelerate. I just never expected the relatively small CFM56 to take a long time as well.
Is it possible you are mistaking the hesitation at 40% N1 as part of the total spool up time when it has got nothing to do with it?
Nope. I know that setting thrust is a two step process. I was looking at the command arc vs the N1 pointer. In both instances, the N1 pointer had a considerable lag, thus my question.
EMIT: Never been in the jumpseat of a PW powered plane. I'll pay attention if I am though.
Thanks all, for enlightening me.