By Keith Bradshaw. All photos by the author and Steve Jeal unless noted.
In December 1968 the world saw the flight of the first supersonic passenger airliner when the prototype Tupolev TU-144 took to the skies in the USSR. Rushed into flight in a bid to become the first airliner of this type, very little testing and development was done This supersonic airliner had many flaws and the fleet of just 17 aircraft only completed 152 flights before the type was grounded in 1983 due to costs and accidents.
Photo : Clipper Artic
TU -144 at the Paris Airshow. Note the complicated retraction sequence of the main undercarriage. This aeroplane was one of the lucky ones and survived to be put on display in a museum at Ulyanovsk.
Meanwhile, Concorde manufacturers BAC/Aerospatiale decided to take a more measured approach and built not only two prototypes but also two pre-production test aircraft. The French prototype was the first to fly in March 1969. With all this test and development work behind them the production aircraft went on to have a very successful career with the British Airways fleet, of just seven aircraft, completing 50,000 flights alone before the types retirement in 2003.
Photo : Andre Cros
Concorde’s maiden flight – the French prototype takes off from Toulouse on 2 March 1969.
Although the first flight was in 1969, it was not until 1976 that the testing and development of Concorde was completed and it was allowed to enter airline service. The two prototypes were essentially ‘proof of concept’ aircraft and differed considerably from the proposed production aeroplanes. The two pre-production aircraft were built to bridge that gap and to carry out most of the system tests once the prototypes had proved the design could fly and meet the original specifications. The pre-production aircraft were testing a new wing shape, new engines, new cockpit visor, new intake control system and many other systems that were not fitted to the prototypes. It must be remembered that in the 1970s much of the testing had to be physically carried out. High-power computer models were not available at that time. Indeed such was the uncertainty that on the initial test flights the crew wore flight suits with fighter pilot helmets, mainly for emergency oxygen and radio communications.
Photo : Dlanor Smada
XDN whilst still being used for testing displayed at the 1974 Farnborough Airshow.
Of the total of twenty Concordes built only two were lost to accidents – the Paris crash and a heavy landing in Dakar. The remaining eighteen have all found homes in museums or airfield displays around the world. The majority of these are ex-British Airways/Air France airliners and are displayed to the public showing the ‘cosiness’ of the narrow cabin and the luxury experience passengers could enjoy.
Photo Hugh Llewellyn
Air France Concorde on the roof of the museum at Sinsheim Germany.
Photo : William Warby
A British Airways Concorde on a barge alongside the USS Intrepid aircraft carrier museum in New York.
But what of the four test aeroplanes? The British prototype can be found at the Fleet Air Arm museum at Yeovilton while its French counterpart is on display at the Musee de l’Air in Paris. The French pre-production example is across the city at Orly airport with Musee Delta. The British pre-production aeroplane G-AXDN had most of its test equipment removed and was delivered to Duxford in 1977 having been transferred by the then Department of Industry to the Duxford Aviation Society. A truly remarkable gesture for such an icon to be donated to a private society. Having first flown in 1971, XDN had, during its test flying, reached the speed of Mach 2.23 (1,450mph) a speed never exceeded by any other Concorde. It also reached a record height of 63,700 feet but this was eventually exceeded by another Concorde. For a time XDN was the highest and fastest flying Concorde in the world!
British pre-production Concorde 101 G-AXDN now owned by the Duxford Aviation Society at its home in the AirSpace hangar. The red dots on the back of the rudder are explosive charges (bonkers) used to induce artificial instability in flight to prove that recovery was possible. It was suggested by a Concorde engineer that they might also be used as a fast method of freeing the rudder if it became jammed !
On arrival at Duxford XDN was outside for nearly twenty years, open to the public. Finally the day came when space was offered by the IWM in their new AirSpace hangar. Following a repaint she was one of the first aeroplanes to be fitted inside the huge new building. With much of her test gear removed before delivery, the space inside the fuselage was taken up by the original Test Engineers’ desk at the front of the cabin, display cases showing the Concorde fleet’s history and airline service at the mid-cabin. At the back some Concorde passenger seats from one of the early British Airways airliners were installed. These, along with catering trolleys and photographs gave some idea of what the production versions had looked like in airline service. These internal displays remained unchanged until 2015.
Photo : IWM
Out of the weather at last, XDN takes her place inside the AirSpace hangar.
Around this time the DAS board took the brave decision to investigate the possibility of returning XDN to how she looked when in service with BAC/Aerospatiale as a test aircraft. This would make her a unique display because nearly all the other Concordes open to the public are the same, luxury airliners. This would be something different and an homage to the derring-do of the original design team and test crews. Under the leadership of David Norman and Chrissie Eaves-Walton a team was formed to look into the various aspects of creating an exhibition and telling the story of test flying in an understandable and exciting way. Joining this team right from the beginning was Heritage Concorde. This is a group of Concorde enthusiasts, some of whom are ex-Concorde flight and ground engineers, whose passion is to help out on the displays on any of the preserved Concordes. The whole re-vamp project is indebted to Heritage Concorde for their assistance.
One major consideration was that the aeroplane was, if at all possible, to remain open for public viewing. This was largely achieved with only one closure for the installation of a new electrical power supply and fitting of new floor coverings. DAS electricians carried out all the wiring on the aircraft and the IWM ran new heavy duty cables to the aircraft from the hangar’s electrical supply. It was also thanks to the IWM that whilst the aircraft was closed they helped with the installation of a CCTV system for security and crowd control. This may sound excessive but on busy days there is often a long queue waiting to get on board. The steward can now stand at the entrance desk watching the monitors and controlling the flow of visitors through the cabin. This makes life much more comfortable for visitors as it can get quite warm inside the fuselage. To entertain the queue, there are large display panels showing various aspects of the Concorde design and test programme and a video screen showing clips of Concorde’s design, manufacture and flight.
The display panels in the queuing area giving details of XDN’s test programme.
Inside the fuselage it was initially a case of out with the old, particularly anything related to airline service. The display cases, photos and seats were all removed and placed in storage.
The seats were replaced with the original seats from 101 that were used for the test engineers to rest during transit to their next test area. The frames for most of these seats were found in the back of a DAS storage container. One however, had to be rescued from the Airfield Fire Service who had used it for years in their ‘smoke chamber’. A deal was done and we swapped it with another more modern seat we had in our collection of bits! All these seat frames were then re-upholstered by DAS volunteer Ray, using period pictures to get the covering correct.
The restored seats for the flight test crew with, in the background, some of the Zonal Units which housed various test and data recording equipment. In the foreground on the right is the high-pressure nitrogen bottle for blowing down the undercarriage in an emergency.
One of the major programmes XDN was involved in were trials to check the efficiency of wing de-icing systems. The leading edge of the port wing was painted black and divided into zones. TV cameras were then positioned in the forward fuselage looking back at the wing and feeding their signals to a bank of monitors in the cabin at a crew position known as the Ice Station. Here a test engineer could observe the build-up of ice and record the speed of melting in order to meet CAA requirements. There is a decal on the forward fuselage of XDN to celebrate its part in the de-icing trials at Moses Lake, USA in 1974.
The aircraft had positioned from England to Bangor, Maine in a flight time of 2 hours 56 minutes setting a record for the fastest east to west crossing of the Atlantic by a commercial airliner.
The Ice Station, reconstructed from scratch, to show one of XDN’s major test programmes. The red beacon on the roof is the ‘abandon aircraft’ light. Not something anybody wanted to see illuminated!
Miss Moses Lake decal fitted to celebrate the de-icing trials at Moses Lake and named after the local beauty queen who joined the crew to celebrate the success of tests.
Looking back towards the rear entrance just some of the 200 miles of wiring can be seen to good advantage. On production aircraft this area was the baggage hold.
In addition to the Ice Station some of the other early improvements during the re-vamp included LED hat rack lighting and new cover panels. These were designed to show off some of the 200 miles of test cables running up and down the fuselage. The LEDs helped to reduce the heat in the cabin. Whilst all this work was being done by the DAS volunteers, the guys from Heritage Concorde had undertaken to get many of the lights in the cockpit and the flight test engineers station working again. These along with the warning lights on the air intake door computers began to bring the aeroplane back to life.
The flight test engineers’ station, with the hyposcope stowed just behind on the left hand side. This was used to check the engine intakes during flight. The row of black and white bottles on the right-hand side are the crew’s oxygen supply.
Not content with just the internal lights, Heritage Concorde also got the landing lights to work along with one of the thrust reverser buckets and helped rig lights within the engine jet pipes. The biggest job they achieved was bringing back to life the nose droop mechanism. For a while, this was the only Concorde to have this function re- activated so that we could do regular nose lowering demonstrations. Heritage Concorde also rigged up a sound recording of a Concorde engine start which is so clear you can even hear the ignitors cracking away as the fuel ignites! As well as help from Heritage Concorde we have also had assistance from other museums such as the Fleet Air Arm Museum at Yeovilton who allowed us to photograph their original Zonal Units on the prototype Concorde and Brooklands museum who allowed us to examine their data tape recorder so we could make a replica.
One of the Olympus engines lit up to represent the afterburners. This engine also has workable thrust reverser buckets.
Thanks to work by the Heritage Concorde team XDN now has a fully functional nose lowering system which is demonstrated monthly. See das.org.uk for dates.
Keen not to lose the luxury airliner story completely, we were lucky enough to be granted long term loan by British Airways Heritage collection of a very large-scale model of a BA Concorde that used to grace the entrance foyer of their headquarters building at Heathrow. With a perspex cabin roof you can see the final seat design that was being fitted to the Concorde fleet after it returned to service following the Paris crash. As you can see, this re- vamp project has involved many other groups from the Concorde world to produce an exciting exhibit.
British Airways’ model Concorde nestles under the Rolls-Royce Olympus engines of XDN.
To enable us to make the Zonal Units, which filled a large part of the fuselage when XDN was test flying, we obtained high quality photographs of the computers in the units from the prototype aircraft at Yeovilton and then had them enlarged to full size. These were then fitted into cabinets to give a good representation of the real thing. The tape recorder, which was used to capture all the test data, was not so easy. Using photos of the real thing from Brooklands (there is some suggestion from details on these photos that the Brooklands unit was once fitted to XDN) we made up a replica with motorised tape reels. Another item that was placed on display in the cabin is the mono-fuel auxiliary power unit. This piece of equipment used a highly combustible fuel to run the unit and provide power in the event of engine-powered generator failure.
A section of Zonal Units which housed much of the test and recording equipment used during test flights.
Other components brought on board for the re-vamp include one of the original rope ladders that were to be used to evacuate the aeroplane if a problem developed on the ground. These were in addition to the two escape hatches which allowed crew to jump from the aeroplane in flight by passing through the underfloor area and a fuselage hatch to parachute to safety. There was also a hyposcope fitted to XDN to enable the engineers to examine the underside of the aeroplane and the air intakes during flight. A replica of this is also on display and with the addition of new clearer signage the visitor experience is now much enhanced.
One of the rope escape ladders.
The data tape recorder copied from the one at the Brooklands museum. The tape reels rotate in the typically jerky fashion of such equipment in the 1970s.
It has been a long road from the initial thoughts of the Duxford board to return XDN to its test configuration. There were doubts, but anybody who has seen the finished project will wholeheartedly agree it was the right decision. To bring this unique aeroplane back to how it was when it paved the way for the production aeroplanes and the safe luxury travel they offered was an inspired idea, somewhat like Concorde itself.
A big thank you to all concerned and congratulations on a job well done.
Photo : Peter Langsdale
The Duxford Aviation Society would like to thank the DAS volunteers and the following for their help in bringing this project to fruition:
Contract Flooring Service
The Design Studio
Screens & Graphics
British Airways Heritage Centre
BAE Systems Archive
Fleet Air Arm Museum Yeovilton