Pratt & Whitney is developing a proposal for a package of performance upgrades for the existing Boeing B-52 engine after the US Air Force again postponed a plan to replace the venerable bomber’s 60-year old TF33 engine.

Several four-engined solutions have been evaluated by the USAF to replace the eight TF33s on board each B-52H.

But the four-engined aircraft may not have enough rudder authority to counter the adverse yaw generated by an outboard engine-out scenario, says P&W military engines president Bennett Croswell.

So P&W proposed a re-engined B-52s with eight new turbofan engines, but the USAF instead decided to postpone the programme, he says.

The TF33 was derived from the original P&W JT3 turbojet engine that drove the first generation of jet-powered Amercian airliners.

P&W is developing an upgrade package to improve the fuel and maintenance performance for the TF33 through the end of its service life. The USAF currently plans to operate the B-52 fleet to at least 2060.

Source: Flight Daily News