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Existing bearing technology has not kept up with improved permanent fasteners that are interference fit installed to improve in-service fatigue life. Bearing net-fit service life problems are, elevated temperature and loss of lubrication, causing rolling contact fatigue and RPM noise, bearing migration, high stress amplitude and fretting fatigue lug failure. The high fatigue bearing is manufactured with a predetermined radial looseness of the outer race. This bearing, when installed into existing hole sizes, the press-fit must exceed the elastic range into the compressive plastic zone of the outer race. Only in the compressive plastic zone is the diameter of the outer race stabilized to maintain radial bearing clearances and fabrication tolerances. This bearing concept may be used on ball, roller and spherical bearings and bushings. It is not intended to replace all existing bearings.

These investigations are conducted to develop new fasteners and joining methods to reduce weight and improve fatigue life of aircraft structures. Three major modes of structural failures; fatigue, fretting and stress corrosion are discussed with recommendations for improvement. Stress coining was developed to cold work aircraft structure for fatigue improvement. Standard stress corrosion test blocks have been designed for evaluation of this failure mode. A crown flush rivet configuration has been developed that does not require head shaving after installation. Qualification tests were performed in compliance with MIL-Std-1312 to obtain FAA and military approval. Various new fasteners have been developed for aluminum, graphite-epoxy and titanium structure. These fasteners were designed to be forgiving to the hole in that they will fill and prestress the hole uniformly without being extremely sensitive to hole preparation quality.