While the A400M program enters a new phase of turbulence, with Germany looking to slash its purchase to 40 from 53 and France looking to renegotiate a maintenance deal, the flight-test campaign is forging ahead with the aim of getting the European airlifter delivered by the end of 2012. The engine problems that surfaced earlier this year have been solved, clearing the path for European civil type certification to be achieved in the coming weeks.
By October 20 the four-aircraft A400M test fleet had flown 2,380 hours in 784 flights, with 1,653 takeoffs and landings. The aircraft had been flown by 60 pilots, including those from French, German, Turkish and UK air forces. Operating from the flight test centers at Sevilla and Toulouse, the aircraft are equipped with telemetry systems that allow specialists at other locations (Bremen, Filton, Getafe and Hamburg) to receive test data in real time.
In recent weeks, the aircraft has completed several major tests, including two of the most iconic performance tests: the HERTO and water-trough trials. HERTO (high-energy rejected takeoff) tests involve using only the brakes to stop a fully laden aircraft from high speed. To satisfy certification requirements, the HERTO must be performed after several minutes of taxiing so that the brakes are already warm, and with the brakes pre-worn to 90 percent.
With the aircraft at its maximum takeoff weight of 141 metric tons, the brakes are applied at liftoff speed, with 24 megajoules of energy being applied per wheel. After the aircraft has come to a stop it has to be left for five minutes without intervention before the fire crews are allowed in to cool the wheels. The A400M test demonstrated not only the ability of the brakes to absorb such punishment without a fire developing, but also the operation of the fuze plugs that deflate the tires to prevent damage to the wheels.
Water trough tests were recently performed at Istres, with the A400M operating at various speeds up to 90 knots and with some use of reverse-thrust. These trials were conducted to ensure that no water was ingested by the engines, and were successful in that respect. They did reveal a minor problem concerning a pad mounted on the main landing gear door, requiring a minor redesign.
Other recent achievements have included crosswind landings, conducted at Hyères, with up to 25-knot winds with gusts to 37 knots. Chief test pilot Ed Strongman reported no problems with these. The A400M uses a crabbing technique for crosswind landing, facilitated by a head-up display mode that presents a vector symbol to indicate the path of the aircraft relative to the ground.
At the end of last year artificial ice shape tests were undertaken to determine the effectiveness of the hot-air de-icing system. Representative ice shapes were installed on the unheated sections of the leading edges and handling qualities checked. These tests led to a redesign of the anti-ice protection system, which is being installed on trial aircraft MSN2 and will be fitted to all production aircraft.
Aircraft MSN4 recently completed hot fuel tests at the Filton plant. The aircraft flew five times with JP4 fuel heated to up to 55-deg C to ensure that all the pumps and transfer systems worked with hot fuel. The gravity feed ceiling was established at 37,000 feet.
Flight Test Goals
Performance tests have been completed and other areas are progressing well. Flight control test completion is awaiting the final iteration of FCS software, while anti-icing trials have been delayed by the unusually benign fall weather in Europe.
MSN6 is the fifth test aircraft, and it has yet to fly. It is virtually complete, and should fly around the end of the year. When it takes to the air is largely a question of whether it is kept on the ground to await the latest modifications, or whether it receives them after its first flight.
Whereas the other four aircraft are filled with instrumentation, MSN6 has a clear cabin, and has already been used for evacuation certification tests. These demonstrated that 115 paratroops and the crew could evacuate the aircraft with only two of the doors available and in complete darkness in less than 90 seconds. The tests were successfully repeated with a mixed cargo/passenger configuration, and 66 stretchers and crew were also evacuated successfully, albeit over a longer time.
With civil certification behind it, the team is gearing up toward military tests next year to clear the aircraft for initial service. “We have good visibility of the risks in the military activities,” said Fernando Alonso, head of flight operations and senior vice president of flight and integration tests. “There is still a lot to do next year, but we believe we have removed much of the risk. We are in as good a shape as we can be at this point.”
Among the trials planned is climatic envelope expansion, using MSN6. The A400M has already operated in -35-deg C at Kiruna in Sweden. MSN6 and its clean cabin are also to be used for ground-loading trials, and a 300-hour functioning and reliability test campaign. It will also be the main customer demonstration vehicle. Consequently it will spend some time “on the road,” visiting airshows and potential customers as part of the reliability tests.
Further military tests required next year are air-dropping, including a full load of 114 paratroops to be conducted with the Turkish army, and defensive-aids tests to validate safe chaff/flare separation and no inter-system interference. Work will also cover the operation of the military mission management system, and the communications suite, including MIDS datalink.
Following 15 dry contacts with a UK Royal Air Force VC-10 made earlier this year, further refueling trials will be undertaken. Airbus hopes to receive the first Cobham 908E hose-drogue units in the spring so that tanker trials can get under way. Rough-field trials will be undertaken, beginning with grass runway operations to be performed at the former East German MiG-29 base at Preschen, near Cottbus.o
The first of six A330 Multi-Role Tanker Transports (MRTTs) is due for delivery to the Royal Saudi Air Force (RSAF) later this month. Aircrews began conversion at Airbus Military’s Getafe, Madrid facility late last month. RSAF Col Al Burikan (right) and Lt. Al Majed (left) are two of the pilots being trained there over the next two months. Meanwhile, the UAE Air Force has also ordered three A330MRTTs, with deliveries due next year.