The composite technology, design and construction of the 787 was proven during a series of testing scenarios conducted beginning in late 2007 and concluding in February 2008. The tests were performed on a composite fuselage test section and were part of Boeing's certification efforts for the 787. Boeing engineers proved the composite barrel design through a series of incremental tests that first took the barrel to limit load, a test condition that simulates the most extreme conditions expected to be experienced in the life of the airplane. Next, the test article was taken to 150 percent of limit load -- a condition called "ultimate load," the level required for certification. Finally, the team pushed the composite section past ultimate load well beyond ultimate load to a destruct-condition maneuver beyond two and a half times the force of gravity. Testers observed audible indications of damage as the test progressed but the piece did not reach the level of destruction that had been anticipated. Boeing engineers then performed an extensive inspection of the barrel and analysis of test results.