Learjet 45 APU
Most early models of the Learjet 45 did not have an Auxiliary Power Unit or APU onboard. When Bombardier Learjet released the Learjet 45 XR, it included a Learjet 45 APU. All Learjet 45 XR jets have a Learjet 45 APU onboard. The Learjet 45 APU is available as a retrofit to older Learjet 45s that do not have an APU.
The Learjet 45 APU is the Honeywell RE 100-LJ APU - Auxilary Power Unit, formerly called the AlliedSignal RE 100-LJ APU. This APU is installed on all original Learjet 45 XR aircraft. It is also available to be installed on Learjet 45s that do not have an APU.
Below are the Honeywell RE 100-LJ APU specifications:
- RE 100-LJ Dimensions: 27.2 inches x 17.3 inches x 16.1 inches
- Maximum Total Weight: 79 lbs
- Electronic Control Unit: Digital
- Basic FAA TSO-C77a, Specification: Category 1
- Bleed Airflow: 35 lbs/min @ 36psig
- Rated Pad Shaft horsepower: 17 shp
- Rotor Speed: 70,200 RPM
Also note that the Bombardier Learjet 45 APU is also the Bombardier Learjet 45 XR APU and the LJ45 APU.
Above photo of the Learjet 45 APU from Honeywell. Photo Copyright Honeywell. Used under the fair use provision.