article_snippet: U.S. safety investigators blamed the pilots, saying U.S. safety investigators bungled the landing approach by inadvertently deactivating the plane's key control for airspeed, among other errors.
article_snippet: But the National Transportation Safety Board also said the complexity of the Boeing 777's auto-throttle and auto flight director — two of the plane's key systems for controlling flight — contributed to the accident.
article_snippet: the National Transportation Safety Board the National Transportation Safety Board also faulted materials provided to airlines by Chicago-based Boeing, saying airlines fail to make clear the conditions in which the auto-throttle doesn't automatically maintain speed.
article_snippet: Investigators said captain Lee Kang-Kuk, a seasoned Airbus A320 pilot transitioning to the bigger Boeing 777, cut the autopilot on final approach into San Francisco, where the instrument landing system was out of service.
article_snippet: Doing so put the auto-throttle on hold, meaning it would no longer automatically control
article_snippet: When the jet dipped below the correct glide path, Captain Lee reacted by pulling the nose up - but the auto-throttle, still on hold, failed to deliver an expected burst of engine power that would have enabled the airliner to make the runway.