G650 Passes Fly-by-wire Backup Tests

Gulfstream described G650 S/N 6001’s recent tests using the electrically powered fly-by-wire (FBW) backup flight-control actuation system as “flawless.” During a three-hour, 33-minute flight, test pilots Jake Howard and Gary Freeman and flight-test engineers Bill Osborne and Nathaniel Rutland evaluated the fly-by-wire system in electric backup actuation mode for two hours and 20 minutes, performing five landings with the backup system engaged. Fly-by-wire systems typically use a third hydraulic system to provide redundancy, but Gulfstream’s FBW architecture for the G650 has electric backup hydraulic actuators–one at every primary control surface (elevator, rudder and aileron) and the outboard spoiler. The test flight began by evaluating electric backup-mode handling qualities in one axis and then progressed to full evaluations in all three axes. Gulfstream said the pilots could not detect any differences between the normal FBW and emergency backup modes in regards to aircraft handling and control.