Thanks to the Honeywell APU the reengined B-52 Stratofortress bomber aircraft will meet operational quick-start requirements without the use of ground support equipment.
As part of the Commercial Engine Replacement Program (CERP) Boeing has selected Honeywell’s proven 36-150 auxiliary power unit (APU) to upgrade the B-52 with an on-wing Auxiliary Starter Air Unit (ASAU). As reported by Aerospace Manufacturing and Design, each ASAU consists of an APU and controller that provides high-pressure air to start the main jet engines before departure.
Thanks to the Honeywell ASAU the reengined B-52 Stratofortress bomber aircraft will meet operational quick-start requirements without the use of ground support equipment, thus enhancing mission readiness and flexibility of aircraft operations.
“The B-52 is one of the most enduring USAF aircraft ensuring force readiness against emerging threats,” said Dave Marinick, president, Engines and Power Systems, Honeywell Aerospace. “We are confident that our proven 36-150 APU will exceed the expectations of the USAF throughout the CERP contract and subsequent B-52 active-duty squadron service that will last until at least 2050. Honeywell auxiliary power systems proudly serve on every generation of USAF long-range strike aircraft, and Honeywell looks forward to continuing to serve the USAF on the next phase of the B-52’s operational life.”
The ASAU is the latest variant of Honeywell’s successful 36-150 APU model series. This new version is equipped with the latest compressor technology originally developed for the commercial aircraft sector, with minor modifications to meet the specified performance and installation requirements of the B-52 ASAU application.

Earlier in 2022, Lockheed Martin Sikorsky-Boeing DEFIANT X helicopter, currently a contender to win the US Army’s Future Long-Range Assault Aircraft (FLRAA) competition, also selected Honeywell’s 36-150 APU for its auxiliary power needs.
Honeywell has a long history of supporting the USAF and Boeing by providing aircraft secondary power systems and APUs. Honeywell secondary power systems are in active service on the F-15, F-22, F-35, and F/A-18 fighter jets. Honeywell APUs are also in active service on USAF C-130 and C-17 transport aircraft, and M32 ground carts.
As already explained, the CERP represents “the largest modification in the history” of the B-52. The new package includes radar, engines, communications, pylons, cockpit displays, and the deletion of one crew member station, meaning “it makes sense” to have a new designation. The B-52H will be redesignated the B-52J or possibly B-52K, but the USAF hasn’t yet decided what will constitute the new B-52 variant.
Since some of the new APG-79B4 radars will be installed on the bombers before the new Rolls-Royce F130 engines, the question is whether there will be two designations. For the version with the new radar the B-52 pilot operating manual and maintenance manuals will be re-written; and will be re-written again when the engines are changed.
Photo credit: Staff Sgt. Sean Martin / U.S. Air Force
