Abstract: A turbofan engine has: an engine core producing a core exhaust flow; an upstream fan; a bypass duct carrying a bypass air flow produced by the fan; an exhaust assembly. The turbofan engine afterburner system has: a core plug; second core flow duct, and entrance(s) from the first core flow duct for diversion into the second of a portion of the core exhaust flow, and exit for re-joining the diverted portion of the core exhaust flow to the undiverted portion of the core exhaust flow; door(s) open during normal operation of the engine but closable, during a reheat operation, to block the entrances to the second core flow duct; and fuel injector(s) and igniter(s) operable, during the reheat operation, to inject and ignite fuel within the second core flow duct, providing a reheat flow into the core exhaust flow from the exit of the second core flow duct.

Abstract: A turbofan engine has: an engine core producing a core exhaust flow; an upstream fan; a bypass duct carrying a bypass air flow produced by the fan; an exhaust assembly. The turbofan engine afterburner system has: a core plug; second core flow duct, and entrance(s) from the first core flow duct for diversion into the second of a portion of the core exhaust flow, and exit for re-joining the diverted portion of the core exhaust flow to the undiverted portion of the core exhaust flow; door(s) open during normal operation of the engine but closable, during a reheat operation, to block the entrances to the second core flow duct; and fuel injector(s) and igniter(s) operable, during the reheat operation, to inject and ignite fuel within the second core flow duct, providing a reheat flow into the core exhaust flow from the exit of the second core flow duct.

Abstract: A pitch change mechanism for a bladed rotor includes a driving sleeve, a drive shaft, a first pitch-changing element, a second pitch-changing element, and a plurality of blade drive gears. The driving sleeve has, in axial sequence, a first helical connection portion and a second helical connection portion. The driving sleeve is positioned concentrically with and surrounding the drive shaft. The first pitch-changing element has a first end drivingly engaged with the first helical connection portion, and a first ring gear portion at a second opposite end, while the second pitch-changing element has a first end drivingly engaged with the second helical connection portion, and a second ring gear portion at a second opposite end. The plurality of blade drive gears are arranged in a circumferential array around a longitudinal axis of the drive shaft.

Abstract: A pitch change mechanism for a bladed rotor includes a driving sleeve, a drive shaft, a first pitch-changing element, a second pitch-changing element, and a plurality of blade drive gears. The driving sleeve has, in axial sequence, a first helical connection portion and a second helical connection portion. The driving sleeve is positioned concentrically with and surrounding the drive shaft. The first pitch-changing element has a first end drivingly engaged with the first helical connection portion, and a first ring gear portion at a second opposite end, while the second pitch-changing element has a first end drivingly engaged with the second helical connection portion, and a second ring gear portion at a second opposite end. The plurality of blade drive gears are arranged in a circumferential array around a longitudinal axis of the drive shaft.