Planning Begins for F136 Flight Tests
Guy Norris guy_norris@aviationweek.com
Los Angeles
Amy Butler abutler@aviationweek.com
Washington
The General Electric/Rolls-Royce team developing the F136 alternate engine for the F-35 Joint Strike Fighter has begun flight clearance work for the start of the test program in early 2011, despite being targeted for cancellation for the third time in the latest U.S. defense budget.
The GE-RR team met formally with Lockheed Martin, the F-35 Joint Program Office (JPO), the U.S. Air Force and Navy at Evendale, Ohio, for flight-clearance technical review meetings May 13-14. The meetings coincided with the resumption of tests on the F136 at GE’s Altitude Test Cell 43 in Evendale, following modifications to the bearing system.
Tests were halted on test engine 625-004 as a precautionary measure in late February after debris was detected in the oil system. Investigations traced the source of the debris to reduced clearance in the differential roller bearing supporting the area around the aft of the high pressure turbine and the forward section of the low pressure turbine. The clearances in the unit, called the C-sump bearing, have been restored to those used on the original pre-system development and demonstration engines.
Tests of engine 005 are expected to begin at the Air Force’s Arnold Engineering Development Center, Tenn., in mid-June. The third engine, 006, will be used for accelerated mission testing to prepare for initial flight release on the F-35. Production engine 041 is designated to power F-35 conventional-takeoff-and-landing test aircraft, AF-1, and is due to be shipped to JSF prime contractor Lockheed Martin in March 2010. Although contracted by JPO to deliver the first engine to support a late 2010 first-flight schedule, Lockheed is not intending to fly the first F136-powered F-35 until February 2011.
Engines 007 and 008 are aimed at short-takeoff-and-vertical landing (STOVL) tests, with 008 undertaking the flight qualification work. GE-RR says that despite the apparent shift in schedule the first F136s remain available as options to JSF customers from 2012 onwards.
The Obama administration’s Fiscal 2010 budget request for the Pentagon, as outlined by Defense Secretary Robert Gates since April, seeks no funds for alternate engine effort - a move that follows similar efforts under the last few years of the George W. Bush administration. Congress has, each year, ignored the move and earmarked funds for both engines.
Indeed, House Armed Services airland subcommittee Chairman Neil Abercrombie (D-Hawaii) voiced strong support for continued funding of the alternate engine during a May 20 hearing. He cited the grounding of Air Force fighters in the 1970s due to use of a single engine, which had problems, as one of his reasons behind supporting the Pratt & Whitney’s F135 effort.
Also during the hearing USAF Lt. Gen. David Darnell, deputy chief of staff for air and space operations, plans and requirements, said that the service hopes to get 110 F-35s in the Fiscal 2010 budget, though the Pentagon’s request only calls for purchasing 80 of the aircraft next fiscal year.
Photo: Lockheed Martin
