Incident Details
A Boeing 747 cargo airplane began taxiing for departure when the crew heard a thump-like noise, which they attributed to the tires passing over a rut. The captain continued taxiing. During the takeoff roll, at approximately 130 knots indicated airspeed (IAS), the captain heard and felt another thump, followed by substantial vibration. He aborted the takeoff at about 148 knots IAS, applying maximum braking and maximum reverse thrust. The airplane reached 166 knots before decelerating and ran off the paved end of the runway into a clearway of soft dirt. It stopped about 486 feet beyond the paved end, as the landing gear wheels sank into the soft terrain. The runway had 11,584 feet of pavement available for use.
Damage Assessment
About 1,500 feet from the beginning of the runway, a large amount of shredded tire debris and gouge marks consistent with tire wheel rims were found. At the final rest point, the number 11 and number 12 tires, installed as the two aft tires on the right body landing gear assembly, were shredded and destroyed. Tires one through four were inflated and undamaged; tire five was cut, torn, and flat; tires six, seven, and eight were flat; tires nine and ten remained inflated; and tires 13, 14, 15, and 16 were flat. The nose wheel tires were undamaged and inflated. Further damage included the underside of the right flap assembly, the right main landing gear hydraulic brake system, a landing gear door, and the brake assemblies.
Weight Information
The airplane's takeoff gross weight for the flight was 794,200 pounds. For takeoff operations on the runway utilized, the runway takeoff gross weight was 795,300 pounds.
