Guy Norris/SEATTLE

BRITISH AEROSPACE, has rebuffed Boeing attempts to sign it up as a partner, on its Joint Advanced Strike Technology ( JAST) programme.

The US contractor says that, "the door is still open" if BAe is prepared to withdraw from its alliance with McDonnell Douglas (MDC) and Northrop Grumman on a competing design.

Boeing is looking to firm up UK industrial participation in its JAST design, which programme manager Mickey Michellich says is now firmly a "multi-role" aircraft and not just a US-oriented "tri-service fighter". Boeing is organising a supplier fair in Seattle later in 1995, which will be attended by representatives of more than 100 UK companies.

"We're prepared to talk about work-share split with or without BAe," says Michellich who says that Boeing has already made several offers to BAe already.

Rolls Royce, which is responsible for the lift-technology element of the short take-off and vertical landing version of all the JAST competitors, remains a key part of the UK contingent.

Michellich says that there is a role for UK companies in landing gear, avionics and so on, for engineering, manufacturing and development demonstrators and production.

BAe is strongly linked to MDC through the Harrier and Hawk programmes. Boeing argues, however, that of the three surviving teams, (the other being led by Lockheed Martin), its direct-lift design more closely resembles the original Harrier concept.

Despite the apparent overtures to BAe, the chances of Boeing teaming with Lockheed Martin remain strong. "We left our discussions [previous teaming talks] with Lockheed in a very friendly situation. We did not close any doors, but we decided to wait for down-select in preparation for the demonstrator programme," Michellich says.

Boeing is beginning to reveal more details of its closely guarded design as it prepares to make the first engine runs in the 94%-scale model at its purpose-built Tulallip site in Washington. "We'll be firing the [Pratt & Whitney F119] engine up in a couple of days," says Michellich who adds that the aircraft's single 2-D vectoring main exhaust-nozzle will not be used for vertical landing.

Two vectoring-lift nozzles will direct exhaust gas downwards for take-off and vertical landing while "up-and-away" power will come from the main exhaust-nozzle.

Pitch, yaw and roll will be controlled, by an attitude control system part of which, will be located at the wingtips. Details of the system remain secret, but Michellich says that Boeing has applied for a patent for the technology.

The lift nozzles are enclosed in forward flight, to reduce drag and improve the low-observable characteristics of the airframe.

Boeing says that the blended delta planform produces a large internal-fuel volume. "We end up with a huge range/payload, at least double or more than any of the aircraft you're trying to replace. Our fuel fraction is 40%."

Source: Flight International