The bearings will be replaced and the Apaches will be returned to duty, spokesman Jim Stueve said. An unknown number of Apaches have a newer kind of tail rotor bearing that will not need to be replaced.
No Apaches will fly until the inspections are completed this week, Stueve said.
The Apache, made by Boeing, is the Army's best attack helicopter and is deployed both in the United States and abroad.
The decision to inspect the full fleet was made when the Army recently determined that the bearing was the cause of an Apache crash last January at Fort Rucker, Ala., in which the helicopter was destroyed and the two-man crew suffered minor injuries, Stueve said. Investigators determined that a heating process used by Boeing to make the bearing assembly extra hard led to stress corrosion fractures in the bearing.