The program was developing the General Electric/Rolls-Royce F136 engine as an alternative to the Pratt & Whitney F135 engine that currently powers the F-35. Successive Administrations proposed terminating the alternate engine program in the FY2007 through FY2010 budgets. On December 2, 2011, General Electric and Rolls-Royce announced that they were ending development of the F136 engine, terminating the F-35 engine competition. In FY1996, Congress required development of an alternate engine for the F-35. Opponents of the Administration's proposal to terminate the alternate engine program argue the following:
The Administration's proposal to terminate the alternate engine program does not comply with Section 213 of the FY2008 defense authorization act ( H.R. Cost Issues

Cost has been a significant issue in the alternate engine debate. DOD officials argue that terminating the F136 alternate engine program poses little operational risk. 1540 includes language barring funds from being spent for performance improvements to the F-35's engine unless the engine is developed and procured competitively, and other language requiring DOD to preserve existing F136 engines and tooling and to allow the contractor to perform research and development on the engine at the contractor's expense. Senate

On May 26, 2011, the Senate passed S. 1867 , the National Defense Authorization Act for Fiscal Year 2012. FY2012 Defense Appropriations Act

			House

On July 8, 2011, the House passed H.R. The bill included no funds for the F-35 alternate engine. (F) The impact that canceling the F136 competitive engine would have on the high-performance military engine industrial base, and on the Department of Defense's ability to make competitive engine choices for future combat aircraft systems beyond the Joint Strike Fighter. The House Appropriations Committee report ( H.Rept. The Committee also directs the Department of Defense to fund the continued development of both engines in future budget submissions. (a) Limitation on Use of Funds for an Alternative Propulsion System for the F-35 Joint Strike Fighter Program.—None of the funds authorized to be appropriated or otherwise made available by this Act may be obligated or expended for the development or procurement of an alternate propulsion system for the F-35 Joint Strike Fighter program until the Secretary of Defense submits to the congressional defense committees a certification in writing that the development and procurement of the alternate propulsion system—
(1) will—
(A) reduce the total life-cycle costs of the F-35 Joint Strike Fighter program; and
(B) improve the operational readiness of the fleet of F-35 Joint Strike Fighter aircraft; and
(2) will not—
(A) disrupt the F-35 Joint Strike Fighter program during the research, development, and procurement phases of the program; or
(B) result in the procurement of fewer F-35 Joint Strike Fighter aircraft during the life cycle of the program. FY2010 DOD Appropriations Bill ( H.R. 5136 states:
F-35 Joint Strike Fighter (JSF) Extra Engine: The Administration strongly objects to the addition of $485 million for the extra engine program and to associated legislative provisions that limit the obligation of overall JSF development funding to 75 percent of the amount authorized until the funds for FY 2011 have been obligated for the extra engine program, require the Secretary to ensure that each budget in the Future Years Defense Plan include, and expend, sufficient funding to continue the program, and designate the F135 and F136 engine development and procurement programs as major subprograms.
On December 2, 2011, General Electric and Rolls-Royce announced that they were ending development of the F136 alternate engine for the F-35, ending what had been a contentious and long-running battle.
The alternate engine program began in FY1996, when defense authorization conferees directed DOD to ensure that the JSF (then "JAST") program "provides for adequate engine competition" and required the Department of Defense to develop an alternative to the Pratt & Whitney F135 engine that currently powers the F-35 Joint Strike Fighter (JSF). Development of the alternative, the General Electric/Rolls-Royce F136 engine, was funded in Administration budgets from FY1996 to FY2006. From FY2007 to FY2010, Congress rejected Administration proposals to terminate the program. In FY2011, Congress agreed not to fund the alternate engine, and the alternate engine program was terminated in April 2011. The Administration's FY2012 budget submission again requested no funds for the program.
Through FY2009, Congress provided approximately $2.5 billion for the Joint Strike Fighter alternate engine program. The program is projected to need an additional $1.9 billion-2.9 billion through 2016 to complete the development of the F136 engine.
Critics of the proposal to terminate the F136 alternate engine argue that termination was driven more by immediate budget pressures on the department than the long-term pros and cons of the F136 program. They argue that engine competition for the F-15 and F-16 saved money and resulted in greater reliability. Some who applaud the proposed termination say that single-source engine production has been the norm, not the exception. Long-term engine affordability, they claim, is best achieved by procuring engines through multiyear contracts from a single source.
Canceling the F136 engine poses questions on the operational risk—particularly of fleet grounding—posed by having a single engine design and supplier. Additional issues include the potential impact this termination might have on the U.S. defense industrial base and on U.S. relations with key allied countries involved in the alternate engine program. Finally, eliminating competitive market forces for DOD business worth billions of dollars may concern those seeking efficiency from DOD's acquisition system and raises the challenge of cost control in a single-supplier environment.
Continuing F136 development raises issues of impact on the overall F-35 acquisition program. It also raises issues of the outyear costs and operational concerns stemming from the requirement to support two different engines in the field.
FY2012 defense authorization bill: On May 26, 2011, the House passed H.R. 1540, the National Defense Authorization Act for Fiscal Year 2012. H.R. 1540 includes language barring funds from being spent for performance improvements to the F-35's engine unless the engine is developed and procured competitively, and other language requiring DOD to preserve existing F136 engines and tooling and to allow the contractor to perform research and development on the engine at the contractor's expense.
FY2012 DOD appropriations bill: The House Defense Appropriations Committee report included no funds for the F-35 alternate engine.