When it comes to transportation flying, speed might not be everything, but it's pretty darn close. So when Gulfstream pilots recently flew the company's under-development G650 flagship to Mach .995, it effectively flew the jet as fast as you can go without creating a sonic boom. It was the fastest reported speed of a bizjet.
The speed mark was achieved during flutter testing in a high-speed dive with 16 to 18 degrees of nose-down pitch, during which time flutter exciters were activated with no adverse effects noted. The flutter margins, the company said, were well within limits.
The fifth G650, serial number 6005, is now coming on line. It will be used for RVSM testing. It joins serial number 6001, the first flight-test aircraft, which is being used for envelope expansion; 6002, which is doing systems and takeoff-and-landing work; 6003, which is the avionics and ice certification test bed; and 6004, which is having a production interior installed and will be used for function and reliability testing.
All told, the G650 test aircraft have amassed nearly 600 hours of flight-test time as part of a projected 1,800-hour flight-test program. Certification is scheduled for 2011 and entry into service the following year.