We remember a few important dates in aviation history, the day the Wright brothers first flew their first powered flight on December 17, 1903, and perhaps May 21, 1927, the day Lindbergh touched down at Le Bourget in Paris after the first non-stop trans-Atlantic flight. There are many, many other dates that are important, but lost in history. For those of us here at Airbus, February 22, 1987 is a date that changed the history of our company. It is the date that Airbus A320 msn 0001 took to the air for the first time.
More than 24 years later, here is just some of the history of a magnificent airplane that we refer to here in Toulouse as simply “Bravo Alpha”. While many prototypes airplanes are cast aside for the latest and greatest that project the designers have in mind, F-WWBA has been continuously in flight test since the day it originally flew. It has been used for aerodynamic improvements, engine testing, system testing, and for test pilot training. When I arrive at work and head for my parking spot, it is always exciting to see BA at its stand next to the abreuvoir (which in French means “watering trough”), and even more exciting to see my name on the schedule to fly this historic airplane.
Developing the all Fly-By-Wire A320 was difficult from many standpoints. Even though the cockpit operating philosophy was similar to the A300 and A310 aircraft which in production at the time, the use of specific control laws in the flight control computers, the introduction of a side-stick controller in a commercial aircraft would be a first and require careful development. In fact, some of the flight-testing of both the side-stick controller and FBW control laws were accomplished on one of the Concorde development aircraft. The final challenge was certifying these new systems, because a new set of rules specific to the A320 had to be developed.
The test pilots for the first flight of F-WWBA were Pierre Baud, VP and Head of Flight Test, and Bernard Ziegler, Technical Director at what was then called Airbus Industrie. I have met both of them since arriving at Airbus in 2006. While Pierre Baud remains a striking presence as a consultant and pilot, Bernard Ziegler can be secure in knowing that his vision and strong push for technical innovation has created a generation of aircraft at Airbus.
My first real flight-testing on BA was in February 2007. The CFM-56 engines (CFM International is a joint venture between the French engine manufacturer Snecma, and General Electric) had been modified with new internal components, so with these “tech insertion” engines, we took the airplane to Iqaluit, Canada for cold weather testing. On the westbound leg, we stopped in Keflavik, Iceland for fuel. On the return leg, we were able to fly non-stop back to Toulouse. On the ramp in Iqaluit in temperatures below -25C (-13F), we did engine cold soak, cold starts, engine runs, and some local flying.
F-WWBA was also used as the primary follower airplane to do wake vortex testing behind the A380. It has become a 4-year, multi-flight program where this one A320 airplane has performed nearly 1,000 wake turbulence encounters behind heavy generators flying in formation with the A380. To accomplish this testing, the airplane was modified with a fin-mounted video camera, differential GPS, and special VHF communications links. As with stall testing, we flew the airplane with many of the FBW protections removed, to simulate a “generic” transport airplane in the ICAO Medium category. The last testing was accomplished in November and December of 2010.
Since then, the airplane has been upgraded with LCD displays to replace the original CRT units. It is equipped with a prototype ADS-B display, which allows the pilot to see the call sign, heading, altitude, and speed of all the airplanes nearby that are equipped with Mode S transponders. It was the prototype for testing the Head Up Display that is now used on the A380, and retains the HUD capability today. We recently certified an electronic flight bag screen that mounts on the sliding window, and the computer docking station that powers it.
Airbus is developing a newer version of the A320 we call NEO (New Engine Option). NEO will be an improved version of the A320, with new engines from Pratt & Whitney and from CFM International. These new engines will be larger in diameter, which will affect the size and aerodynamics of the inboard slat on the leading edge of the wing between the engine nacelle and the fuselage. One of the tests we accomplished last summer was with modified slat shapes to determine any changes in lift coefficient, which required doing a lot of stalls. To do stalls in a fully protected FBW airplane, we use the instrumentation system to temporarily allow testing at high angle of attack.
Airbus trained two Chinese test pilots last year, and I flew in BA with both of them to teach stall testing, and velocity for minimum control with engine out testing. Also in the last year, I have been involved in flight-testing of handling characteristics where individual spoiler panels have been extended asymmetrically. And we have also been testing winglets on the airplane. To date, the airplane has had 4 different types of winglets tested, to the point where it was becoming difficult to adapt all the different fasteners required to the existing holes at the wingtips.
With the announcement that Airbus would design new winglets for the A320, to be called “sharklets”, we knew that it would be necessary to completely re-certify the flight characteristics of the airplane. This will include stalls, handling qualities, speed for minimum unstick on the ground, and cruise performance testing, to name just a few. As a result, we needed to perform “baseline” testing on BA. One of the more interesting and demanding tests I performed in BA was baseline testing to determine the exact velocity for minimum control with one engine inoperative. This is done with an engine actually shut down (not at idle, as we do for training), and it is done beginning at 1500 feet agl. Minimum speeds reached were on the order of 112 knots in the approach configuration, which is very slow for this type of airplane.
With baseline testing completed, F-WWBA entered a 6-month working party to prepare the airplane as a NEO test bed. The first step was opening both wings at the wingtip to strengthen the structure to accept the loads produced by the sharklets. The second step was opening and modifying the rear fuselage for strength and to accept installation of the skid plate that will be used in the velocity for minimum unstick, which is where the tail is flown down to where the skid plate just touches the runway, so that the airplane lifts off at minimum speed in the takeoff configuration.
When BA first went into working party, I met with the Test Flight Engineer who has managed all the difficult maintenance on this airplane over the last 15 years, Jean-François Azzopardi. We put on our required hard hats, and walked around the airplane as the technicians prepared to remove the horizontal tail. Then we found a window in the office space that overlooks the hangar, and took the attached photo at almost exactly the same spot and aspect (although not the same final assembly building) where the airplane was parked during final assembly in April 1986, just over 25 years ago.
Now with nearly —– hours and —— test flights to it’s credit, F-WWBA is once again proving itself to be so much more than just the prototype of an airplane that generated a family of modern aircraft. Once thought to be economically unviable, and that only a few hundred of the type would be sold, I flew A320 msn 4724 last week, A330 msn 1274 flew last week, and so did A380 msn 86.
And what of the future? After the sharklets and full envelope testing is complete next year, we envision that F-WWBA will become the test bed airplane for many of the enhancements expected to be in place for NEO. It may include testing of both the Geared Turbofan from Pratt & Whitney and the Leap-X engine from CFM International. We expect that this historic airplane will continue in flight test until 2015, when the A320 NEO makes it’s first flight and F-WWBA takes a final bow and fades into history.
I am going to say once again how important it is for everyone to have safety on their minds when flying. The year 2011 has already seen enough accidents to indicate that the trend continues in the wrong direction. Make it your mission, above all, to operate as safely as you can. Somebody once said, “The air is good, stay away from the edges of the air”. And make sure you to help your fellow aviators when you are standing on the solid edge of the air.