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Boeing
Flight testing of the Boeing 777-300ER has verified the performance of numerous special features. One such feature, Tail-Strike protection, helps prevent tail contact with the ground on takeoff. Operating through the airplane's fly-by-wire flight controls, the system allows the airplane to lift off at reduced speed, increasing allowable takeoff weight by 4,000 to 10,000 pounds (1,814 to 4,536 kilograms), depending on airport conditions and airplane structural limits.
"It's in the primary flight computer," said Frank Santoni, Boeing 777 chief pilot, of the special feature. "It's a function that looks at rate of closure of the tail to the ground during rotation, measuring how fast and at what distance the tail is moving toward the pavement."
If the tail gets too close to the ground, the system moves the elevator for slower nose rotation. During abuse takeoff testing, where Santoni has deliberately rotated the airplane early and fast, the system has responded as designed.
"It's doing a superb job, which is testament to our engineering team," Santoni said. "On the 777-300 program six years ago we did the same takeoff performance tests and contacted the tail about 12 times, which is expected during flight-test. On this program, we haven't touched once."