GE Aviation and Rolls-Royce ended their self-funded development of an alternative engine for the F-35, bowing to Pentagon opposition and looming, deep reductions in U.S. defense spending. The engine manufacturers announced their decision in a joint statement on December 2, citing “continued uncertainty in the development and production schedules” of the Lockheed Martin F-35 JSF.

The companies had formed the Fighter Engine Team in 2002 to produce the F136 engine, a 40,000-pound-thrust class turbofan, as an alternate to the Pratt & Whitney F135. The F136 program was the result of engine prototypes and patented technologies from both companies, developed over 14 years with $3 billion in taxpayer funding. Rolls-Royce was a 40-percent partner in the joint venture.

The Pentagon had opposed the second engine option for the F-35 since the Bush administration as costly and unnecessary, but advocates in the U.S. Congress kept the program alive. However, in February the House of Representatives voted to stop funding the F136, slated to receive $450 million in Fiscal Year 2011, and the Pentagon then cancelled the program.

Advocates of the F136 serving on the House Armed Services Committee revived the alternate engine in draft legislation for the Fiscal Year 2012 defense authorization act, but only after GE and Rolls-Royce agreed to self-fund the program during Fiscal Years 2011 and 2012.

F136 engine development was nearly 80 percent complete. When the Pentagon terminated the program in April, six F136 development engines had accumulated more than 1,200 hours of testing since early 2009, according to the companies.

The decision to stop internally funding the engine appeared driven by the prospect of $1 trillion in defense budget cuts over the next 10 years, required by deficit-reduction legislation passed by Congress this summer. The JSF program is considered a prime target for slowed or reduced production. “GE and Rolls-Royce are proud of our technology advancements and accomplishments on the F136,” stated Dan McCormick, president of the engine joint venture. “However, difficult circumstances are converging that impact the potential benefit of a self-funded development effort.”