Fuel efficient descent
Could anybody please give me a FACTUAL answer to this question please:
How much fuel is likely to be saved in a descent from approx FL350, by adopting a 'thrust levers closed' descent, ie as per FMC (or FMGC), rather than a managed descent in V/S or FPA at approx 1000' per min, starting 10 to 20 miles earlier?
Interested really in A320 answers.