Guy Norris/Los Angeles

The Joint Strike Fighter (JSF) competition heated up further on 24 October when Lockheed Martin's X-35A JSF concept demonstrator aircraft completed its first flight from Palmdale, California, to nearby Edwards AFB.


The X-35A used just over 600m (2,000ft) of runway to take-off before climbing to 10,000ft with the gear down. "The climb performance was spectacular for not having any afterburner," says chief test pilot, Tom Morganfeld, who was at the controls for the 22min flight. "It flew exactly as we expected," he adds.

The undercarriage was retracted after an initial handling-quality assessment for landing approach. The only issue during the flight was an indication that a landing gear door was not properly closed, although this was thought to be a problem with a micro switch.

Morganfeld says the aircraft achieved 250kt (465km/h) indicated airspeed at 10,000ft and a maximum angle of attack of 10.4í, which is the X-35A's normal approach angle. Lockheed Martin intends to open the envelope to 40,000ft and M1.5. Initial envelope expansion work is due to finish by the end of November when theX-35A will return to Palmdale for conversion to the X-35B short take-off and vertical landing variant. The X-35C CV (carrier version) is, meanwhile, being readied for flight "about a month behind".

Lockheed Martin expected to resume X-35A test flights as Flight International closed for press. Morganfeld adds that "within the next week" the afterburner will be used and supersonic flight achieved. Full manoeuvring will not be explored with the X-35A, which is stressed for 5.5-6g, but with the structurally stronger X-35C. If chosen for engineering and manufacturing development (EMD),in-service variants will be stressed to exceed 9g.

EMD selection is due in the late second quarter or early third quarter of next year. The US Department of Defense recently released a call for improvements, which Boeing and Lockheed Martin will respond to in January. The only full partner, the UK, is due to decide this month whether it will participate in EMD.

Boeing is investigating what caused a brake system warning light to illuminate during an X-32A test flight on 24 October.

Source: Flight International