Boeing 787 Dreamliner structure test a success

Citation

(2008), "Boeing 787 Dreamliner structure test a success", Aircraft Engineering and Aerospace Technology, Vol. 80 No. 6. https://doi.org/10.1108/aeat.2008.12780faf.003

Boeing 787 Dreamliner structure test a success

Article Type: Mini features From: Aircraft Engineering and Aerospace Technology: An International Journal, Volume 80, Issue 6

Alenia Aeronautica, a Finmeccanica company, successfully completed destructive testing on the horizontal stabiliser of the Boeing 787 Dreamliner. The test took place at Alenia’s Pomigliano Plant in Naples with boeing engineers and representatives of the US Federal Aviation Administration (FAA) and European Aviation Safety Agency in attendance. The stabiliser is made at the Alenia Aeronautica plant at Foggia in Italy’s Puglia region.

Previous physical testing had shown that the horizontal stabiliser meets its certification requirement to withstand 150 per cent of the maximum aerodynamic load it ever could encounter in flight. Once Alenia engineers proved that, they then tested the horizontal stabiliser to see just much load the horizontal stabiliser could withstand before failure.

In that test, the structure did not break until well in excess of the required 150 per cent of limit load. The destructive test was the culmination of seven months of testing conducted by Alenia and Boeing.

“This is quite an achievement”, said Nazario Cauceglia, Alenia Aeronautica’s Chief Technical Officer. “The test validates the innovative multispar design concept and consolidates the spirit of co-operation established between Alenia and Boeing engineers on this difficult task, and on the entire 787 program.”

“Successful completion of the 787 horizontal stabiliser failure test marks the culmination of an innovative design and development activity”, said Randy Harley, Vice President and General Manager, 787 Engineering and Technology. “Working together, the 787 team has once again confirmed the power of an integrated partnership.”

Previous tests at Pomigliano gauged the structure’s capability to withstand various extremes in aerodynamic pressures, such as upward and downward deflection and extreme asymmetric loads.

With static testing complete, Alenia now will proceed to fatigue testing. Alenia engineers at Pomigliano will subject a complete horizontal stabiliser to repeated flexing, meant to demonstrate the stabiliser’s ability to carry repeated operational load cycles representative of its design life. To obtain certification the tail will be tested to at least three times its design life. The testing program is slated to conclude with Boeing conducting a bird strike test at its facilities in the USA.

Boeing has also completed the Power On sequence for the first 787 Dreamliner, marking the completion of the next major milestone on the path to first flight later this year.

Power On is a complex series of tasks and tests that bring electrical power onto the airplane and begin to exercise the use of the electrical systems. The 787 is a more-electric aeroplane with the pneumatic, or bleed air, system being totally replaced by electronics.

“The team has made great progress in bringing the bold innovation of the 787 to reality”, said Pat Shanahan, Vice President and General Manager of the 787 Program. “There is plenty of work to be done between now and first flight, but with every step forward we grow more and more confident.”

The Power On sequence began in early June with a series of pretest continuity checks to verify that the wiring installed in the aeroplane had been connected properly. Upon completion of those checks, the Boeing team plugged in an external power cart and slowly began to bring full power into each segment of the system, beginning with the flight deck displays. From that point forward, the pilot’s controls were used to direct the addition of new systems to the power grid.

At each step of the testing, power is allowed to flow into one additional area and gauges are used to verify that the right level of electrical power reached the intended area.

“We are very methodical in ensuring the integrity of the aeroplane’s systems”, said Shanahan. “In completing the Power On sequence, we have verified both that the electrical power distribution system is installed as designed and that it functions as intended.”

Work will continue to finish building the first 787 and further test its readiness for operations. First flight is expected in the fourth quarter.

The Boeing 787 Dreamliner is said to be a more fuel-efficient mid-sized jetliner capable of serving on long-distance routes. The 787 is expected to enter revenue service in 2009 after an extensive flight test program.