Boeing is focusing on slow-speed handling characteristics of the X-32A in carrier version (CV) mode as it works to resolve problems with the aircraft's large undercarriage, which it has so far been unable to retract.
The company, which had flown the Joint Strike Fighter concept development aircraft (CDA) four times by 29 September, says: "We are working on it, but we are not overly concerned as we think we understand what the problem is."
The Messier-Dowty built main gear is designed to retract forwards into the wing, and is unusually long because the wing is positioned high off the ground to prevent the "suck down" phenomenon caused by the exhaust from the engine nozzles when in vertical landing mode.
Boeing is making the most of the problem to explore the slow-speed handling envelope as part of its early focus on CV performance.
The aircraft was flown by US Navy Cdr Philip Yates for the first time on 28 September. In CV mode the aircraft's large vortex lift flaps, aligned close behind the leading edge, are also deployed as part of plans to reduce approach speeds to as little as 115kt (210km/h).
Boeing also began runs of theX-32B short take off and vertical landing version's Pratt & Whitney JSF119-614 engine on 21 September.
The aircraft is expected to make its maiden flight in the first quarter of next year.
Source: Flight International
