Active sidestick operations make so much sense to most pilots that talk of anything else seems a waste of time. Sidesticks are a mainstay in business aircraft like the newest Falcons, recent Embraer jets and Airbus aircraft. The Cirrus fleet of single engine piston aircraft even sports a sidestick of sorts. There’s a difference though between these sidesticks and the system undergoing certification inside the new Gulfstream G500. The Gulfstream’s system is an active sidestick configuration, rather than a passive version like some others.
The practical value of active versus passive sidesticks became clear during the investigation of the 2009 Air France 447 accident in the South Atlantic. The aircraft, an Airbus A330, was equipped with passive sidesticks. That meant that in the dimly lit cockpit of the Air France jet that stormy night, the pilot in the left seat was unaware of precisely what inputs the right seat pilot flying the aircraft the pilot was using as he attempted to regain control of the aircraft after an upset. Specifically, the flying pilot was holding full aft stick on the A330, essentially keeping the 242-ton aircraft’s wing stalled. The Airbus never changed that attitude until it struck the water.
In an active sidestick cockpit, any manipulation of one sidestick would have been duplicated on the other side of the cockpit. Had the two pilots attempted to fight each other for control of an active sidestick configuration, those efforts would have easily been felt by both pilots through the force feedback system built into the stick.
When the dream that evolved into the G500 first emerged in Savannah, use of a sidestick became an important consideration because of the cockpit real estate it would open up by eliminating those two traditional control wheels. The G500 would be Gulfstream’s first sidestick airplane and early research convinced Dan Nale, “If it wasn’t an active sidestick, it wasn’t going on a Gulfstream.” Nale is the company’s senior vice president for programs, engineering and test.
Enter BAE Systems, with military fly-by-wire, active sidestick control experience dating back to the Joint Strike Fighter. BAE was also hungry to enter the civil market. The result became the G500 active sidestick system, BAE’s first civil installation.
Active Benefits
Active sidesticks provide pilots with real-time feedback to keep each cockpit crewmember in the loop. The sidesticks mimic a traditional control-wheel setup and move in conjunction with each other, including when the autopilot is flying the aircraft. Imagine the additional situational awareness active sidesticks might have made for that Air France crew.
Gulfstream’s vice president of flight operations Collin Miller says the precision movements of the new sidestick significantly improve the G500’s handling qualities because the “sidestick senses a pilot’s physical input and tailors the flight experience to the amount of force the pilot uses.” Gulfstream and BAE both believe the sidestick system with triple redundancy is nearly failure proof. But should a gremlin appear, the sidestick would, at worst, default to a passive mode allowing the crew to maintain full controllability. BAE Systems booth at NBAA is C11646.
