Damaged in Aug. 19 due to a landing gear failure, the WhiteKnightTwo (WK2) launch aircraft will return flight along with the Virgin Galactic’s SpaceShipTwo (SS2) as Scaled Composites is poised to resume captive carry flight tests of the latter aircraft.
Flight tests of the unconventional four-engine mother ship resumed at Mojave, California, on Sept. 13 following repairs to the left vertical tail and modifications to the main landing gear. The undercarriage was beefed up with what senior Scaled management describes as a minor modification, plus an additional fail-safe redundancy.
The functional check flight evaluated performance with the gear fixed down, as well as a simulated SS2 glide mission and approach. The flight, which included two touch-and-go approaches, involved pilot proficiency work and evaluations of engine pylons, rudder repairs, lateral stability and environmental-control systems.
Scaled Composite says the Aug. 19 gear failure occurred while the crew was performing touch-and-go maneuvers. “Upon the fifth nominal touchdown, the left-hand main gear partially retracted. Flight-test engineer Marc Zeitlin immediately annunciated the anomaly and pilot Pete Siebold called for an abort while holding centerline. Meanwhile, co-pilot Clint Nichols secured the engines and systems.”
According to the company, a subsequent test flight, also made with the gear fixed down, was recently completed with no further issues.
Envelope expansion work with the space vehicle attached will still be possible with the gear deployed due to the relatively high-power capability of the WK2’s four Pratt & Whitney Canada PW308A engines.