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A380 nears certification
By Sebastian Steinke
Toulouse airport at 2.51pm on a sunny 13 November. The cockpit crew onboard MSN002 comprises Airbus test pilots Ed Strongman and Michel Gagneux, plus EASA test pilot Didier Poisson. Flight “AIB 101” takes off with only 70 passengers in the fully furnished cabin for one of the last major tests of the A380 before certification, which is planned for mid-December: Technical Route Proving.
This intensive programme entails 150 hours of racing around the globe under simulated airline conditions. Far from its home base, the aircraft will be up against the harsh reality of routine operations. No longer will hand-picked technicians be available every night along with the complete maintenance arsenal to restore the prototype to top condition after a tough day at work. Instead, everything – luggage and cargo, refuelling, service water, drinking water, kitchen waste, cleaning, replenishing the galleys, boarding and last but not least, ongoing maintenance – must function correctly under time pressure and in some cases under extreme weather conditions too. Officials are constantly present in the cockpit, carefully noting down every detail of operational performance.
By 1 December, four flight series will have taken the A380 all round the world. The first flight scheduled is from Toulouse to Singapore in 12 ½ hours, then on to Seoul-Incheon and back to Toulouse; the second flight is from Toulouse to Hong Kong, Tokyo-Narita and then back to Toulouse; the third is from Toulouse to Guangzhou (Canton), Peking, Shanghai, Guangzhou and then back to Toulouse. The high point is a flight from Toulouse to Johannesburg, then southwards to Sydney via the South Pole. From there the route will take the aircraft northwards to Vancouver and back to Toulouse via the North Pole. Airbus is also using these test flights to make the final adjustments to the A380's autoland system. In particular, due to the unusual terrain profile on the final approach to Johannesburg some calibration flights are planned under which the electronics have to deliver a clean approach despite confusing signals coming from the radar altimeter.
As of mid-November, the small test fleet comprising the first five A380's had completed 2,370 out of the 2,700 flying hours planned. On 12 November MSN004 paid a flying noon visit to Düsseldorf airport as guest of the “Travel Supermarket” trade show being held there, and attracted no fewer than 115,000 spectators to the airport, among them Minister-President Rüttgers of North Rhine Westphalia and Lufthansa CEO Mayrhuber. On 16 November the same aircraft flew to Iceland to demonstrate five take-offs and six landings under an extremely strong cross-wind of up to 74kph, with gusts as high as 104kph – another of the requirements for certification on 13 December. The final hurdle will be the Maximum Energy Rejected Takeoff Test planned for MSN001 on 6 December, under which take-off is aborted at the maximum energy of 105 megajoules, in the total absence of any wind.
The A380's test schedule will continue in the New Year: for Configuration Deviation List Certification, a number of faults and abnormalities which could occur in service later on have to be demonstrated. These include flying with a missing winglet or with a faulty landing-gear door, also simulated ferry flights without passengers but with one unserviceable engine, as might occur during a flight to the maintenance shop. Another 50 flying hours are required for the optional head-up display (HUD) in the cockpit. Airbus test engineer Fernando Alonso, Vice President Flight Division, explains, “We have eight months' extra time, and we want to make the best possible use of them.”
At the beginning of 2007, MSN002 is scheduled to undergo cold weather tests with the test cabin. Each of the two decks has been fitted out with a cabin interior from a different manufacturer. However, MSN007, also with a fully fitted cabin which already incorporates many of the design details specified by launch customer Singapore Airlines, will be used primarily for demonstrations to customers and for PR purposes.
Robert Lafontan, Senior Vice President Engineering A380 Programme at Airbus, summarises the present state of the programme as follows. “When it enters into service the A380 will still be 2% heavier than the planned manufacturer's weight empty [MWE, i.e. without galleys and passengers seats] of 234.2 tonnes.” In fact, however, apparently 3% is quite normal in the industry in the early days of a new aircraft. “Apart from 200 to 300kg, we are today exactly at the point that we predicted in December 2003. Extra requests from customers, for example, an extra position for freight pallets, have made the aircraft heavier,” Lafontan explains.
To save weight, apparently the materials used in rear section 19 were changed to composite materials after the programme launch. By replacing aluminium with sections of aluminium lithium in the wing, up to another 10 tonnes could be saved.
It is customary for an aircraft to be optimised over the production period, in the course of which it becomes consistently lighter. “What comes out of production today, stays as it is. But if we can improve something in the future, then we will do so. The basic process is the same on all aircraft.” 30 aircraft are currently at various stages of production. Many new improvements have already been incorporated into the manufacturing process. Another round of modifications has been agreed but not yet implemented. To date over a tonne has been eliminated.
The range-payload figures promised for the Rolls-Royce Trent engines have been adhered to. Meanwhile, a total of 400 flying hours of measurements with MSN009 and the GP7200 engines from Engine Alliance will last another two months. “But it is looking good,” says Lafontan, who, as a fully qualified test pilot also sometimes sits at the A380 controls himself and, for example, flew the aircraft on the visit to Düsseldorf mentioned above. On the subject of wiring, Lafontan has this to say: “We have to design and build. We are currently on schedule. The German side has just been sent some design tools from the French team.” From MNS025 onwards, the aircraft will be fitted with the final, redesigned cable harnesses.
From FLUG REVUE 12/2006
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