Patent ID: 8562284
Filing Date: 2013-10-22
Classification: F02C,F02K,F05D

Abstract:
1. A propulsive fan system comprises a fan unit comprising: a first stage array of rotatable blades coupled to a first drive means; a second stage array of rotatable blades coupled to a second drive means, wherein: a variable area exhaust nozzle operable to be variable in area in dependence upon an operational state of the first stage array of rotatable blades and the second stage array of rotatable blades, wherein at least one of the first stage array of rotatable blades and the second stage array of rotatable blades comprises means for locking the at least one of the first stage array of rotatable blades and the second stage array of rotatable blades into a non-rotatable configuration while the other of the first stage array of rotatable blades and the second stage array of rotatable blades is operable to rotate.