Airbus Fly-by-wire Visionary Bernard Ziegler

DALLAS - Via a press release, Airbus informed today that Bernard Ziegler, former VP of engineering and fly-by-wire evangelist, passed away at the age of 88.

With the launch of the A320 in 1988, Ziegler, one of Airbus' engineering pioneers, was instrumental in the world's first digital Fly-By-Wire (FBW) and side-stick controls in a commercial passenger aircraft. FBW controls pioneered by Airbus are now the standard in the airline industry.

https://youtu.be/cyaMl7StBTI

Bernard Ziegler

Ziegler had a long and illustrious career that spanned four decades. He saw the full potential of digital FBW, including the integration of flight envelope protection into the control software. Ziegler's legacy lives on in the form of digital FBW on all current-generation Airbus aircraft, as well as its implementation as a global standard on all new passenger aircraft.

Ziegler was born in Boulogne sur Seine in 1933 and attended several engineering and flight training schools (Ecole Nationale de l'Air, Ecole de Chasse, Ecole Nationale Supérieure de l'Aéronautique, Ecole du Personnel Navigant Essais). He served in the French Air Force as a fighter pilot for ten years.

The Airbus A320, *with its novel FBW systems*, was also piloted by Ziegler. Photo: Alberto Cucini/Airways

He studied aeronautical engineering at Toulouse's ENSA (Ecole Nationale Supérieure de l'Aéronautique), which is now ISAE-SUPAERO, in the early 1960s. After that, he went to the prestigious EPNER flight test pilot school before pursuing a career as a military test pilot.

In 1972, Ziegler joined Airbus as its chief test pilot and was tasked with establishing a new flight test division. He put together a team that shared the design office's and partner countries' goals, encouraging flight test crews and design engineers to collaborate.

Being a test pilot, Ziegler flew the first flight of the first A300 in 1972 as well as the A310, A320, and A340-200. Up until his retirement in December 1997, Ziegler was Airbus's Senior Vice President of Engineering. He was the son of former Airbus CEO, Henri Ziegler.

*Sidestick control* on an Airbus A320. Photo: Christian Winter/Airways

Fly-by-wire Systems

Fly-by-wire systems are computer-controlled, semi-automatic aircraft flight control systems that use an electronic interface to replace mechanical flight controls. Computers often keep an eye on sensors all over the plane to make automatic changes that improve the flight.

Electrical signaling on secondary flight controls, which replaced the traditional web of cables and pulleys, was one of the A300-600 and A310's notable developments, states Airbus.

With the next aircraft, Airbus co-founder Roger Béteille decided to take this evolution even further, to computer-controlled digital "fly-by-wire," in which the deflections of the flying control surfaces on the wing and tail are no longer driven directly by the pilots' controls, but rather by a computer that calculates exactly which control surface deflections are required to make the aircraft react as the pilot desires.

A simple side-stick control would replace the pilots' control column.

https://youtu.be/PeUh8TXghC8

Flight Envelope Protection and the Concept of Commonality

Fly-by-wire technology on the A320 was used for more than just improving flight controls and reducing weight. By implementing flight envelope protection, it allowed Airbus to take safety to a new level. The A320's pilots were free to fly the plane freely, but the flight envelope protection stopped the plane from performing maneuvers that were beyond its capabilities.

Fly-by-wire was also key in solidifying the idea of commonality, which is so essential to the appeal of Airbus aircraft to customers. No matter how one aircraft varies in size or weight from another, FBW commonality allows the pilot to fly them in the same way because the computer “drives” the aircraft’s flight controls.