In an aerospace industry first, the US Federal Aviation Administration (FAA) has certified BAE Systems’ Active Stick technology for use in civilian aircraft. Standard equipment on the new Gulfstream G500 business jet, the new technology provides tactile feedback to fly-by-wire systems, allowing the pilot to feel how the aircraft is handling instead of only relying on instruments.
Fly-By-Wire (FBW) is one of the miracles of modern aerospace engineering. Since it became industry standard for larger aircraft about 25 years ago, it has revolutionized civilian aviation. Previously, all aircraft were controlled by means of wires, cables, pulleys, and hydraulics. This added considerable weight to aircraft, hampered design, and even with servo motors it placed a serious limit on the size of airframes.
However, FBW changed things considerably. By replacing mechanical control systems with electromechanical actuators controlled by digital computers sending commands via data links, aircraft were now lighter, easier to maintain, had fewer design constraints, and could be any size desired from a control system point of view.
In addition, FBW meant that the pilots had an ever-attentive computerized co-pilot on hand that constantly monitored and adjusted the flight systems. This took a lot of work off the shoulders of the pilot and also allowed aircraft to operate with a degree of precision that was previously unimaginable. In fact, the computer could keep the aircraft within the flight envelope so well that many military fighter aircraft today would be literally unflyable without FBW.
However, FBW does have its drawbacks. Not the least of these is that operating a computer joystick reduces flying to the feel of a video game. In aircraft using mechanical systems, the pilots could fly “by the seat of their pants.” That is, they could feel the feedback from the controls and determine how well they were flying as if the plane was an extension of their bodies.
Until now, FBW didn’t have that. But BAE Systems’ Active stick, also called active control sidesticks or active inceptors, changes that. First developed for military fighters and first certified for use in the Lockheed Martin F-35 Lightning II Joint Strike Fighter, it analyzes what is happening to the aircraft’s control system and feeds that data back to the joystick, so the pilot can feel what is happening in situations like an excessive bank angle or a stall.
“The certification of our active sticks on the G500 marks the completion of an eight-year development program,” says Ehtisham Siddiqui, vice president and general manager of Controls & Avionics Solutions at BAE Systems. “We originally developed a variant of this technology for the F-35, and Gulfstream will now be the first in business aviation to offer our active control sidesticks to its customers.”
The Active Stick system was awarded the 2017 Aviation Week Technology Laureate Award and will be installed in all Gulfstream G500 jets.
Source: BAE Systems