Boeing B747 APU variant selected for Airbus A3XX

Pratt & Whitney Canada (P&WC; Longueuil, PQ, Canada) will provide its PW9XX auxiliary power unit (APU) - a new version of the model now flying on the Boeing 747 - for the proposed Airbus A3XX aircraft.

Based on the PW901A, P&WC says the new PW9XX was designed specifically for A3XX requirements and will be updated in the areas of aerodynamics, materials, and engine controls.

The PW901A provides pneumatic power for main engine start, cabin environmental control, and has drive pads for two airframe-supplied generators that provide electrical power on the Boeing 747-400 aircraft.

Main components include:

• gas generator section incorporating a single-stage centrifugal compressor driven by a single-stage turbine;
  
• annular reverse flow combustor with 14 air-blast fuel nozzles and dual high-energy igniters;
  
• full authority digital electronic control (FADEC);
  
• single-stage load compressor driven by a single-stage turbine; and a
  
• load gearbox incorporating mounting pads for two 90-kVA AC generators.

Edited by David Robb
Managing Editor, AerospaceOnline.com