B-52 engine replacement progresses

The USAF’s effort to re-engine its fleet of 76 B-52Hs is yet to be funded, but the service has articulated its requirements to industry. (USAF)

The USAF has laid out three potential plans to re-engine its fleet of 76 Boeing B-52H Stratofortresses to allow the 55-year-old bomber fleet to operate beyond 2050.

At a December 12 industry day, the service outlined its requirement that any replacement engine must be new build, must provide at least 20 per cent improved fuel burn whilst maintaining or improving current takeoff performance and service ceiling, will replace the eight existing TF33s one-for-one rather than some earlier options which offered four larger turbofans, and that it must be able to be integrated to the old airframe with minimal structural changes.

The USAF is also interested in increasing the power generating capacity of the aircraft to support new weapons, sensors, and possibly a digital engine control system.

While there is still no program of record to re-engine the B-52, an effort that would result in at least 600 new engines being acquired, but the USAF has requested “initial seed funding” in its 2018 budget to continue its studies into the possibility.
The service says that if an engine manufacturer and integrator is chosen in the next 12 months it could modify two test aircraft with engines in FY2022. Further, if the test program is successful, 74 engines sets could be acquired in each year from FY2026 to 2034.

Rolls-Royce has previously indicated its interest in the program by offering the BR725, a variant of the F130 engine that powers the E-11 BACN (Bombardier Global Express) and C-37 (Gulfstream G550).

Comments

  1. Ben says

    So take the ‘easy’ option by sticking with 8 smaller engines (and markedly cutting into your maintenance and fuel savings)?? Or do they still want the fun of starting 8 engines, monitoring 8 engines and having a fist full of 8 throttles?

    Not to mention the much dreaded 7 engine approach!

    Back of the napkin math suggests the PW F117 (PW2000) would be suitable and already serving the USAF reliably on another Boeing product – the C17. Removing the thrust reverse (or locking it out) for B52’s would reduce the engineering required since the pylon would only be subjected to forward thrust. Unsure of the weights but surely 2xTF33 would be ball park the same as a single F117. With half the engines and the massively reduced fuel flow of not only half the engines but the relatively efficient PW2000 design (especially compared to the geriatric TF33) should do wonders for the BUFFs dispatch reliability and range!

  2. Jasonp says

    Ben, I read on AA a few months ago that the 4-engined option had already been disregarded, as the vertical stab doesn’t have enough authority in the event of an engine failure on climb out.

  3. PAUL says

    Probably too much modification & cost required to run 4 larger engines & would possibly require some removal & disassembly of the wing, if not a full rebuild, Also with such a long wingspan have you seen how much the wing tips drop on a B52 when fully fuelled, so ground clearance would also become an issue for the outer engine with large diameter modern turbofans.