Variable area nozzle for a gas turbine engine

A jet pipe and variable area final nozzle assembly for a gas turbine engine, comprising:

• a jet pipe having a downstream end;
• a plurality of nozzle flaps each connected by means of a fixed pivot to substantially the downstream end of the jet pipe for pivoting movement to vary the outlet area of the nozzle, a portion of each flap extending upstream of said pivot and overlying said jet pipe;
• an outer fairing having a maximum diameter substantially equal to the maximum jet pipe diameter, fixed to said jet pipe and surrounding the downstream end of said jet pipe and said nozzle flaps, said jet pipe being necked downstream of its connection to the fairing to a diameter more nearly equal to but not less than the maximum throat area of the nozzle;
• an annular space defined by the necked portion of said jet pipe and portions downstream therefrom, and the corresponding portions of said outer fairing;
• and
• an actuation system disposed in said annular space, comprising:
• a translatable ring disposed around said jet pipe;
• an actuating mechanism connected to said fairing for translating said translatable ring;
• and
• interconnecting means for interconnecting said translatable ring and said nozzle flaps, to operate said flaps, said ring being interconnected to said flaps upstream of said pivot and being located upstream of said pivot, said actuating mechanism being connected to said fairing on the downstream side of said translatable ring, the translation of said ring causing the pivoting of said flaps.