GENERAL ELECTRIC is to be given the opportunity to compete with Pratt & Whitney, on the power plant for conventional variants of the Joint Advanced Strike Technology (JAST) programme, because of a US Congressional edict directing the US Department of Defense's programme office, to conduct a competition to power conventional variants of the aircraft.
All three airframe manufacturers, or teams, now working on JAST have selected derivatives of P&W's F119 to power advanced short/vertical take-off and landing (ASTOVL) variants of their designs.
The Congressional edict means that, for the US Air Force and Navy conventional take-off and landing variants of the JAST, GE will be given an opportunity to challenge P&W, although the F119 may remain the power plant of choice for the US Marine Corps and Royal Navy ASTOVL variants.
GE, with Allison Engines, is offering JAST designers growth variants of the F110 engine, which now powers the Lockheed Martin F-16 and Northrop Grumman F-14, and the YF120, which was beaten by the F119 in the competition to power the Lockheed Martin/Boeing F-22.
Two F110 growth steps are being offered, the DF3/DF6 providing 20-25% more power than the 130kN (29,000lb)-thrust F110-129, by using the up-rated core from the latest CFM56-7 commercial turbofan and the DV2/DV3 providing 35-40% more thrust, through the use of a higher-airflow bladed-disc (blisk) fan and variable-cycle core.
Two variants of the 155kN-class YF120 are being proposed: the V4 providing a 20-25% thrust increase, with a blisk fan and variable-cycle core; and the F3 providing 40% more thrust, with a 50% airflow increase and a fixed-cycle core.
The formal memorandum of agreement (MoA) between the UK and USA on formal UK participation in the Joint Advanced Strike Technology (JAST) programme has been sent to Congress for final approval. JAST technical director, Dr Ronald McErlean, says: "The MoA is about to be signed, for the Royal Navy to be fully aboard."
Source: Flight International