$2.4 billion contract award near for F136 powerplant

The General Electric/Rolls-Royce Fighter Engine Team (FET) was on the verge of officially clinching a long-awaited $2.4 billion system development and demonstration (SDD) contract for the F136 engine on the Lockheed Martin F-35 Joint Strike Fighter (JSF) late last week.

Neither of the members of the engine team are commenting, but Lockheed confirms that the SDD award is imminent, with all parties having agreed on terms and conditions by 18 August. The SDD phase is expected to run from 2005 until September 2013, with F136 initial service release planned for 2012. The F136 is competing on the F-35 against Pratt & Whitney’s F135 engine, the first of which is due to be delivered to Lockheed at the end of the year in preparation for the start of flight tests in 2006.

The SDD contract covers the production and qualification of 14 engines: seven for ground test and seven (including one spare) for flight tests. The first F136 to run is to start tests around mid-2008, although FET president Bob Griswold has said that earlier tests will begin in the second quarter of 2007 using one of the original test engines to address some risk-reduction items on the afterburner.

Flight tests on the F-35 are to start in 2010, with production engines available for Lot 4 of the low-rate initial production run in 2012. The first full F136 engine began tests in July 2004. GE has responsibility for 60% of the programme, and is developing the five-stage all-blisk compressor at the heart of the design as well as the controls and accessories, structures and the afterburner. Stages three to five of the compressor are inertia-welded, with all five stages configured with forward swept aerofoils. The GE-developed single-stage high-pressure turbine is combined with the first of the three-stage low-pressure turbine in a coupled, vaneless counter-rotating system. R-R, with 40% of the programme, is responsible for the three-stage fan, single annular Lamilloy combustor, three-stage low-pressure turbine and gearboxes.

Several changes are planned for the SDD engine based on tests of the initial pre-SDD engines and the JSF’s thrust growth requirement. These include upping the inlet fan flow and slightly adjusting the sizing of the core. Compared with the original YF120-based engine, sized for the higher-thrust requirement of the direct-lift Boeing JSF contender, the pre-SDD F136 engine was a 92.5% scale. This is now being adjusted to around a 95% scale for the SDD phase.

GUY NORRIS/LOS ANGELES

Source: Flight International