Beginning at the design phase, every element of an airplane is examined and evaluated to determine how it performs both separately and in conjunction with other parts and systems. Boeing uses a “building block” testing approach, starting with raw materials and separate parts and subsystems; working up to larger, more complex assemblies and systems; and finally including the entire airplane. Each new airplane that rolls off the line undergoes functional, ground and flight testing before delivery.
Using this building block testing approach, Boeing conducted more than 5,000 hours of laboratory testing of the 787 battery system, including baking the battery to induce overheating, crushing the battery and puncturing a cell with a nail to induce short circuiting.
The airplane’s integrated power system, which includes the batteries, underwent more than 25,000 hours of laboratory testing to demonstrate the interaction of various system elements in normal operations as well as in simulated failures.
At the airplane level, the integrated electrical system underwent more than 10,000 hours of testing under normal operations and simulated conditions, including extreme weather, long and short flight durations, and low and high elevations.
The 787 model completed 5,000 hours of flight testing and an equal amount of test time on the ground, all of which demonstrated that the airplane performs as designed. The 787 successfully completed Boeing’s own program to test and validate the design as well as the most robust certification program ever conducted by the FAA. The 787 electrical system was certified along with the airplane on Aug. 26, 2011.