Paul Lewis/WASHINGTON DC
The US Navy is being encouraged by competing engine manufacturers to consider future options for either introducing an all-new engine for the Boeing F/A-18E/F fighter to improve the Super Hornet's performance or to upgrade and uprate the aircraft's General Electric F414-400.
Officially the USN has no defined requirement or money to re-engine or upgrade theF/A-18E/F's twin engines. If the US Government scraps or defers the Joint Strike Fighter (JSF), this will almost certainly affect the navy's Super Hornet buy, currently pegged at 548 aircraft, and investments in further improvements.
Pratt & Whitney is promoting the PW7000 as a F414 alternative in the expectation that a requirement will emerge by 2003. The PW7000 was conceived for the cancelled AX programme and has since been proposed, without success, as an alternative engine to the Dassault Mirage 2000, Korean Aerospace/Lockheed Martin T/A-50 and Saab/BAE Systems Gripen.
The PW7000 would use the combustor, high-pressure turbine and compressor from the commercial PW6000 along with a scaled low-pressure turbine and fan from the JSF119 engine. The engine is sized as a F414 drop-in replacement, with a 5:1 bypass ratio and up to 25% more thrust. P&W claims it would extend F/A-18E/F range by 31%, increase acceleration by 27% and boost meantime between overhaul to 1,000h.
F/A-18E/F critics have highlighted the aircraft's slower speed relative to the F/A-18C/D and the 22,000lb (98kN) F414's lack of growth potential. GE counters that it has proposals to uprate thrust by 15-20% or significantly extend engine life to address the USN's desire to cut support costs.
GE's proposed improvements include swept three-dimensional blades promising increased efficiency and lower temperatures as well as a new two-stage fan.
GE's improvements are funded with company and navy science and technology money. P&W hopes to win funding to build and test a demonstrator in 2003.
Source: Flight International
