85-15-04: Tail Rotor Blade Yolk P/N 74-641-057-9

85-15-04 BELL HELICOPTER TEXTRON, INC., HAWKEYE ROTOR AND WING, TEXAS HELICOPTER CORPORATION: Amendment 39-5186. Applies to Model 47B, 47B3, 47D, 47D1, 47E, 47G, 47H-1, 47G-3, U.S. Army Model OH-13E helicopters certified in any category and other helicopters equipped with tail rotor blade yoke P/N 74-641- 057-9. Compliance is required as indicated, unless already accomplished. To prevent the failure of the tail rotor blade yoke, accomplish the following: a. Within the next 10 hours time in service after the effective date of this AD, remove from service Texas Helicopter Corporation tail rotor blade yoke P/N 74-641-057-9. b. Any equivalent method of compliance with this AD which provides an equivalent level of safety may be used when approved by the Manager, Helicopter Certification Branch, Federal Aviation Administration, 4400 Blue Mound Road, Fort Worth, Texas 76106. c. In accordance with FAR Sections 21.197 and 21.199, flight is permitted to a base where the replacement required by this AD may be accomplished. This amendment becomes effective January 8, 1986, as to all persons except those to whom it was made immediately effective by priority letter AD 85-15-04, issued July 23, 1985, which contained this amendment.