General Electric and Rolls-Royce team prepares for critical evaluation and testing in effort to secure key contract

The General Electric Rolls-Royce Fighter Engine Team plans to start tests later this month of the first F136 short take-off and vertical landing (STOVL) engine for the Lockheed Martin F-35B Joint Strike Fighter (JSF).

The move follows the successful completion of the first phase of tests on the conventional take-off and landing (CTOL) version of the engine, and is an important precursor to the expected award of a system development and demonstration (SDD) deal around October.

Tests on the CTOL engine began at GE's Peebles, Ohio outdoor evaluation site last July and, after the first phase was completed in December, resumed early this year. Initial test work covered basic performance assessment, fan stalls and risk-reduction work.

GE says the engine "demonstrated smooth starts, throttle transients, stall-free operation, low vibration levels and included a run to 105% maximum design speed".

Tests of the STOVL version, fitted with the R-R-developed three-bearing swivel duct, roll-posts and shaft-driven, two-stage counter-rotating lift fan, are expected to total over 300h and are scheduled to conclude in May 2005.

Work will include critical evaluation of the control integration function, which distributes thrust between the forward-mounted lift fan, outboard-mounted roll posts and aft-mounted swivel duct. For this phase of tests, the engine is fitted with the lift fan developed for the pre-SDD phase, and will undergo durability tests, time at temperature and thrust measurements.

GE, which is responsible for 60% of the F136, is developing the high-pressure (HP) compressor, and coupled HP/low-pressure (LP) turbine system, controls and accessories. R-R, which has 40%, is responsible for the front fan, combustor, second and third stage of the LP turbine and gearboxes.

Tests of the STOVL version of the Pratt & Whitney F135 engine, against which the F136 is pitted for later production batches of the F-35, began in April 2004.

The P&W engine, which performed sustained runs to "hover thrust" demonstrating over 39,000lb (175kN) of thrust in the vertical take-off mode, was followed by another F135 powerplant that was used for endurance tests at West Palm Beach, Florida from last August.

Two other STOVL engines were also introduced to the test effort last October, one going to the Arnold Engineering Development Center, Tennessee, for simulated altitude tests and the other used for aircraft integration work.

GUY NORRIS / LOS ANGELES

Source: Flight International