Beyond Fly By Wire
Even before fly by wire becomes the standard, companies have been exploring the next steps to remove hydraulics from the aircraft control equation. In mid-October, Gulfstream successfully demonstrated primary aircraft flight-surface control using "fly-by-wireless" technology. And, last week, Bombardier announced it had executed a first test flight with an all-electric Meggitt braking system, called EBrake. For the earlier test, Gulfstream outfitted a GV test aircraft with mechanical, fly-by-wire, fly-by-wireless, and fiber-optic fly-by-light systems to control ailerons, outboard spoiler, mid-spoilers and inboard spoilers respectively. Pilots noted consistent handling regardless of the applied control-actuation technology and Gulfstream noted that test results make fly-by-wireless -- and its benefits of reduced complexity and weight -- a potential backup for other flight control systems. Bombardier's test of the EBrake system during normal, emergency and parking-brake functionality showed improved control in normal and emergency modes "resulting in tight centerline control even during maximum brake applications," according to test pilot Gary Bruce. The system couples brake-by-wire control with electric brake actuation and removes relevant hydraulically actuated control systems, with the benefits of increased reliability and (fire) safety, decreased maintenance and associated costs. Both Gulfstream's fly-by-wireless and Bombardier/Meggitt's EBrake systems could reduce system weight on aircraft while removing toxic hydraulic fluids and therefore can claim environmental friendliness as side benefits to improved performance.