Concorde / NEO thermal de-bow
Interested in the de-bow function of Concorde & similar - long shaft, variety of exotic alloys & fine tolerances for max perf meant a current (?) was applied to the shaft pre-start & post-cutoff to even the thermal gradients and stop the shaft bowing. The NEO now has a pre-start equalisation cycle for the same reasons.
Was Concorde the pioneer for needing de-bowing?
Was this a current or just a bleed spin-up?
Do any other powerplants do this today?