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A400M flight-test personnel face an intense period as they work to achieve the end-of-year goal of gaining civil certification for the European military airlifter.

But program officials are reasonably confident that they will meet the target, although it means logging more than 100 flight hours per month to reach the 2,700-hr. goal by the time the milestone is reached; the total test program is expected to top 3,700 hr. “We are clearly on track” for civil type certification, asserts Cedric Gautier, who heads the project.

The flight-test campaign is due to receive a big boost around October, when MSN6, the fifth aircraft, joins the program. Powerplant installation, painting and other final elements remain to be completed on the aircraft.

Through May, the four A400Ms currently involved in testing had clocked more than 1,600 hr. during 500 flights.

The focus is now entirely on flight testing, which marks a turnaround for the airlifter, since cost overruns and schedule delays plagued the program for more than two years. After difficult discussions, government and industry officials have now figured out how to cover the extra costs and handle the three-year delay in fielding the A400M, with governments agreeing to shoulder more of the development bill in return for royalty payments on exports. Germany and the U.K. also trimmed their buy by seven and three aircraft, respectively, to stay within their budgets.

As officials reassessed the program, consideration also was given to easing performance requirements. But Gautier says that, in the end, the decision was made to relax the schedule while not backing off on performance.

Under the new road map, Airbus Military and its customers agreed on a phased introduction of new capabilities, called standard operational clearances (SOC). The first of these, SOC 1, is due for fielding in late 2013, at which point the basic military performance of the aircraft should be validated. The upgrade series should see SOC 1.5 ready in 2014-15 (introducing aerial load delivery), SOC 2 in 2015-16, SOC 2.5 in late 2017 and the final configuration, SOC 3, in 2018-19.

Ultimately, the A400M will be able to meet its low-level flight requirement. Developing the Thales flight management system (FMS) to handle the stringent specification was one of the major concerns as the program was rescoped. Gautier says both Thales and Airbus Military believe the new schedule can be met and that all of the FMS milestones are currently on track.

Much of the work now under way is related to the initial operational capability (IOC) standard.

The full-stall program has been completed, as well as VMU (minimum unstick speed) and VMCG (engine failure on takeoff) testing. To meet VMCG requirements with the powerful TP400D turboprops, Airbus Military engineers have devised a system in which the opposite engine automatically spools back up to 25% of thrust depending on the speed at which the failure occurs. This ensures that the aircraft remains within the allowed variance from ­centerline.

Chief test pilot Ed Strongman says that, among other lessons, the flight trials demonstrated the value of the head-up display. “The HUD has been fantastic for the flight-test program; we use it all the time as the primary flight display,” he says. As a result, he is recommending that the civil development activities make greater use of the HUD.

Flight testing has yielded several areas for design changes, although Strongman says fixes have been identified for most issues that have emerged so far. In the coming weeks, a series of systems upgrades is planned that should bring the aircraft up to the civil type certification standard.

Additionally, the aircraft suffered a “snaking movement” at high speeds. That was a problem also encountered on the Transall C-160 and, as was ­previously the case, the installation of small vortex generators on the bottom of the fuselage eliminated the phenomenon.

The nose landing gear also showed buffet during early trials. Airbus has now installed an air deflector in the landing-gear bay and added small openings in the bay door to control pressure variation during gear cycling.

In some cases, the changes are actually improving overall system performance. A case in point is the deicing system, which needed to be adjusted owing to buffet experienced during tests with artificial ice shapes. In addition to changing what aircraft elements needed to be deiced, the trials showed “that we had been over-conservative in setting the protection in the landing configurations,” says Strongman.

The angle-of-attack systems are set to give protection with and without ice on the airframe. “We have taken advantage of the over-conservatism to move the protection system back closer to the stall angle of attack,” he says. “This extra margin allows us to fly at slower speeds on military approaches, and this gives shorter landing distances.”

The natural-icing series still has to be completed. Airbus Military, meanwhile, has completed two cold-soak campaigns for the airlifter at Kiruna, Sweden— one down to -21C and the other to -38C. More tests are planned.

Furthermore, an initial campaign in Francazal, France, to determine how the A400M would fare when landing on an unimproved runway yielded information regarding where pipes and other structures should be rerouted to provide better protection from damage by stones or other debris.

More recently, flight testing at low aircraft weights has provided some positive feedback, indicating that there should not be a minimum control speed (VMCA) limitation. The VMCA is so low that stall speed will be the limiting factor at the lower end.

Operations in hot weather and high altitude also must be conducted. Other near-term test activities include water-ingestion tests, slated for this month at the French flight-test center at Istres; maximum rejected-takeoff testing; and cross-wind trials at more than 22 kt.

Airbus Military pilots have also carried out initial formation flying to assess flight controls in such a configuration; some adjustments may be made to improve aircraft handling during air-to-air refueling. The mock refueling flights also were valuable in seeing how the TP400D propellers will handle the airflow loads.

Flight testing also has validated the models used to design the aircraft. Modifications made to major structural elements are “quite low,” says Gautier. Although there were concerns about the A400M’s weight, “right now, we have a serial-production configuration that meets the expectations,” he notes.

Ground tests also are continuing. Having completed ultimate-load testing last year with MSN5000, the article is now being used for fatigue-cycle trials of the wing to aid with the type-certification process. Once those tests are completed, this aircraft will be used for damage-tolerance assessments.

The other major ground-based activity involves MSN5001 in Dresden, Germany. It completed the type certification in February and is now in the midst of logging 25,000 simulated flights, representing 2.5 times the A400M’s design life. That activity is due to last until mid-2012.

The goal is to wrap up all this work well before customers start to receive their first aircraft.

Although the delivery schedule could still change, the current plan calls for France to accept three of its 50 aircraft in 2013 (Airbus Military is trying to deliver the first early) and Turkey to see the first of 10 that year as well. The U.K., which is buying 22, would follow in 2014, followed by Germany, which is acquiring 53. Malaysia, the first export customer, could receive the first of four airlifters in late 2014 or early 2015. Spain is waiting for the introduction of the SOC 2 standard and will then begin taking delivery of its 27 in 2015; the combined buyers of Belgium (seven) and Luxemburg (one) are on the schedule for 2018-19.

MSN7, the first aircraft for customers, is to undergo final assembly starting in the fourth quarter, with first flight due in the summer of 2012. The fuselage is being equipped in Bremen, Germany; the same process is under way in Filton, England, for the wing. Gautier says other major structural elements, such as the central wing box, nose, and vertical and horizontal tailplanes also are being completed on schedule.

Moreover, construction is starting on elements for subsequent airlifters, with Filton, for instance, working already on the outer wingbox of MSN8. Series production was formally launched in February and is slated to ramp up to 2.5 aircraft per month in 2015. Airbus has capacity to build more, but higher output would require significant success in the export market.

Other program activity includes preparing to start the pilot and ground-crew training courses. Enrique Vazquez del Rey, head of Airbus Military’s training center, says the first A400M simulator is due to join the CN-235 next year and the C-295 version is already in place in Seville, Spain. The French air force should receive its first ­simulator roughly concurrent with the aircraft.