F-35 Alternate Engine Program: Background and Issues for Congress

Jeremiah Gertler
Specialist in Military Aviation

In 1996, Congress required the Department of Defense (DOD) 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 requests no funds for the program.

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.” Through FY2009, Congress has provided approximately $2.5 billion for the Joint Strike Fighter alternate engine program. The program is projected to need an additional $1.9-2.9 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 singlesupplier 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.


Date of Report: June 15, 2011
Number of Pages: 67
Order Number: R41131
Price: $29.95

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