Nice short mini doco here at Boeing.com on the Engine Out testing being performed on the 787-900.

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.

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