When testing any new airplane, like the new Boeing 787-9 Dreamliner, the Boeing Test & Evaluation team leaves no stone unturned in making sure the plane performs safely, even under extreme circumstances. Few tests exemplify this more than what is referred to as “abuse takeoffs” or “engine-out” testing. “Our engine-out testing is some of the highest risk stuff that we do,” said Boeing Test & Evaluation test director, Brian Hull.
In this testing, air crews intentionally force the airplane to take off with significantly reduced engine thrust. “We do the testing to simulate a take off where if an engine were to fail… we provide the speeds for the line pilots so that they can safely either continue to take off or reject the takeoff,” said 787-9 Senior Project Pilot Mike Bryan.
It’s high risk testing, which means high preparation. Particularly for another simulated engine failure test called “velocity for minimum control on ground” or VMCG. In this test, while the airplane accelerates for takeoff, the crew suddenly and intentionally turns one engine off. One of the pilots immediately responds with full rudder to keep the plane tracking down the runway. The idea of this test is to make sure the airplane will not veer or “deviate” more than 30 feet to either side once an engine is out.
To the untrained observer, this type of testing can appear very dramatic. But the BT&E test team has taken every measure to eliminate the drama. “If it’s not safe, we’re not doing it,” said Hull.