All five Gulfstream 650 test aircraft are now flying

The fifth and final Gulfstream 650 test aircraft took off from Savannah on 24 January and
performed a 2 hour 46 minutes flight reaching a speed of Mach 0.94 and achieving an altitude of 51, 000 feet.

The high mach number was achieved to validate the aircraft’s maximum speed for stability
characteristics, a requirement for receiving a Certificate of Airworthiness from the Federal Aviation Administration (FAA). Such high speeds are outside the aircraft’s normal flight envelope. The Gulfstream 650’s maximum allowable speed is Mach 0.925.

All the aircraft systems were evaluated during the flight. Before its first flight, the aircraft underwent certification ground tests for lightning and high-intensity radiated fields (HIRF). Performed at the company’s headquarters in Savannah throughout November and December, the lightning test indicates the airframe and systems can withstand a severe lightning strike, while HIRF testing demonstrates the ability of the aircraft’s flight essential systems to withstand external radio frequencies without interference.

The company expects to achieve certification of the Gulfstream 650 later this year.