T84-18-51: Main Rotor Spindles

T84-18-51 BELL HELICOPTER TEXTRON, INCORPORATED: Telegram issued September 7, 1984. Applies to Bell Helicopter Textron, Incorporated, Model 214ST helicopters certified in all categories that are equipped with main rotor spindles P/N 214-010-103-003 (Airworthiness Docket No. 84-ASW-42). Compliance is required as indicated. To prevent possible failure of the main rotor spindles, accomplish the following: A. Remove from service any spindle with 1250 or more hours time in service on October 15, 1984, and thereafter at intervals not to exceed 1250 hours time in service. B. After the effective date of this AD, for aircraft with spindles which have, or attain, 1250 or more hours time in service, perform a daily inspection of the main rotor spindle as prescribed in Bell Alert Service Bulletin 214ST-84-24 or other FAA approved equivalent procedure. Remove any cracked spindle from service and replace with a serviceable spindle. C. After the effective date of thisAD, replace all spindles having, or attaining 1250 or more hours time in service, within the next 150 hours time in service or October 15, 1984, whichever occurs first. D. The helicopter may be flown to a repair base for the above inspection under the provisions of FAR 21.197. E. Any equivalent means of compliance with this AD must be approved by the Manager, Helicopter Certification Branch, Federal Aviation Administration, Southwest Region. F. Bell Helicopter Textron, Incorporated, Telegraphic Alert Service Bulletin 214ST- 84-23 is an equivalent means of compliance with this AD. This airworthiness directive becomes effective upon receipt.