20001227041499A

(-23) On takeoff roll crew felt a thump & then a bump. Crew could not get the a/c to pressurize, once in flight so they diverted into ewr. At 0830 on 12/28/2000 the northwest cmo notified the teb FSDO, & requested that we take a look at the a/c at ewr. The aircraft had struck something on its takeoff roll. A threshold light cover is suspected. The thump that was heard by the crew was the nose gear striking the object, causing a large chunk of rubber to be missing down to the tire core, throwing the object into the underside of the fuselage, which was the bump the flight crew heard. The object hit the underside of the fuselage causing a 2 ft. in diameter hole, and broken stringers. The #1 DME antenna was sheared off & the #2 VHF antenna was damaged. (.4) during the takeoff roll, the flight crew heard a "bang;" however, the pilot continued the takeoff and began a climb. The flightcrew was unable to pressurize the passenger cabin, and elected to divert the flight to another airport, where the airplane landed uneventfully. Inspection of the airplane revealed a gash about 3 feet long, by 1 foot wide on the underside of th e fuselage, aft of the passenger entry door, and damage to the right nose gear tire. Inspection of the runway at the departure airport revealed an in-ground light cover, that weighted about 100 pounds, was separated from its mount, broken in two pieces, and lying on the runway. Black marks, consistent in color and texture to rubber, and resembling a tire tread, were observed on the optical lighting well, and on the underside of the light fixture. The light cover was part of an in-ground, semi-flush mounted approach lighting fixture installed at the approach end of the runway in 1997. The lighting system had not been commissioned as of the date of the accident due to lack of certification from the FAA. Examination of the light fixture revealed that the six bolts, which were utilized to attach the lighting assembly to the in-ground base, were sheared. The fracture surfaces on the bolts were smeared, consistent with low cycle fatigue fractures that occur over a period of time. The bolts were located on the underside of the fixture, and to inspect them, required removal of the fixture cover. Repairs and inspections of runway lighting facilities at the airport were conducted at varied intervals;however, due to the lack of being commissioned, the in-ground, semi-flush mounted approach lighting fixtures installed at the approach end of the runway were only visually inspected. The runway was inspected for debris and general condition on a daily basis, or on a duty manager shift change, in accordance with 14 CFR part 139.