Gulfstream flew a G650 flight-test aircraft for the first time using only an electrically powered, fly-by-wire backup flight-control actuation system, the airframer said Wednesday.
Gulfstream’s Serial Number (S/N) 6001 flew for a total of 3 hours and 33 minutes on Dec. 21, 2010. Test pilots Jake Howard and Gary Freeman along with flight-test engineers Bill Osborne and Nathaniel Rutland evaluated the fly-by-wire system in electric backup actuation mode for 2 hours and 20 minutes of the flight, performing five landings with the backup system engaged.
“The system performed flawlessly,” said Pres Henne, senior vice president, Programs, Engineering and Test, Gulfstream. “There was no difference in handling qualities between the electrically and hydraulically powered modes.”
Typically, fly-by-wire uses a third hydraulic system to provide redundancy in the event of a dual hydraulic system failure. However, Gulfstream’s fly-by-wire architecture uses electric backup hydraulic actuators (EBHA), which are electrically controlled actuators that are primarily hydraulically powered but offer electric power as a backup. The EBHAs for the G650 are provided by Parker Hannifin. A self-contained hydraulic reservoir and motor pump allow full operation should hydraulic loss occur, according to Gulfstream.