The US Defense Department's Joint Strike Fighter (JSF) programme office is playing down concerns that the differing operational requirements of the three US services and the UK's Royal Navy are threatening to increase the cost of the programme.
Most of the worries surround potential changes to the outer mould line of the aircraft because of requirements for different weapon systems, such as an integrated gun and varying internal bomb bay configurations.
JSF programme director Maj Gen Leslie Kenne says, however, that "at this time, the requirements are still within acceptable limits".
"All the services have agreed on requirements that will still present a family," she says.
Kenne's comments come as testing begins on both the Pratt & Whitney engines for the two competing JSF variants. The JSF119-611 engine for the Lockheed Martin X-35 CTOL (conventional take-off and landing) and CV (carrier-based) versions began test runs on 11 June, followed 10 days later by the first runs of the JSF119-614 engine for the Boeing X-32 contender.
A second set of engines for the STOVL(short take-off and vertical landing) versions of both contenders are in assembly and will begin ground-testing in the fourth quarter of 1998.
Pratt & Whitney says that a little over 20h have been accumulated on the two engines out of a planned programme of more than 2,500h involving a total of 12 test engines.
Lockheed Martin will conduct tests of JSF scale models at the Netherlands National Aerospace Laboratory's low-speed wind tunnel beginning in August. The Netherlands is participating in the international JSF programme as an associate partner.
The Netherlands Government has made a total of $75 million available for Dutch companies to use in pursuing technologies applicable to the JSF.
Lockheed Martin recently received its first proposed statement of work from Dutch industry for several activities of this type.
JSFcompetitor Boeing also hopes to expand Netherlands involvement in its JSF work.
Source: Flight International
