Patent attributes
A gas turbine engine (10) comprises a first compressor (16), a combustor (22) and a first turbine (24) arranged in flow series. The first turbine (24) is arranged to drive the first compressor (16). The first compressor (16) has variable inlet guide vanes (38) and the first turbine (24) has variable inlet guide vanes (42). A second compressor (48) is arranged upstream of the first compressor (16). An auxiliary intake (12) is arranged upstream of the first compressor (16) and downstream of the second compressor (48). A valve (54) is arranged upstream of the first compressor (16) and downstream of the second compressor (48). The valve (54) is movable between a first position in which the second compressor (48) supplies air to the first compressor (16) and a second position in which the second compressor (48) does not supply fluid to the second compressor (16) and the auxiliary intake (12) supplies fluid to the first compressor (16). A drive means (60,62,64,66) is arranged to selectively drive the second compressor (48).
