Los Angeles Airways Flight 417 - NTSB Recommendation & FAA Reaction

NTSB Recommendation & FAA Reaction

Following the initial evidence of a metal fatigue type failure, the National Transportation Safety Board recommended on August 16, 1968 to the Federal Aviation Administration:

Based on its preliminary findings in the Compton crash investigation, the Safety Board today is recommending to the Federal Aviation Administrator that he (1) require an immediate fleet inspection of all Sikorsky S-61 helicopter spindle units; (2) adopt a more precise and frequent inspection to preclude future spindle unit failures; and (3) study the need for establishing a retirement life for this vital part.

On the same date the FAA issued Emergency Airworthiness Directive 68-19-07. The directive has since been amended twice and now requires the following action:

(a) Before further flight, remove main rotor blade spindles P/Ns S6110-23325-1, S6110-23325-2, and S6112-23025-1 that either have been "salvaged" in accordance with procedures set forth in paragraph entitled "Salvage of Spindle" contained in Sikorsky Aircraft Overhaul Manual for the pertinent helicopter model, or have accumulated 3000 or more hours' time in service on the effective date of this AD, and replace with blade spindles of the same part number that have not been "salvaged" and that have less than 3000 hours' time in service.

(b) Replace main rotor blade spindles P/Ns S6110-23325-1, S6110-23325-2, and S6112-23025-1, that have not been "salvaged" and have less than 3000 hours' time in service on the effective date of this AD, before the accumulation of 3000 hours' time in service with main rotor blades spindles of the same part number that have not been "salvaged" and have less than 3000 hours' time in service.

(c) Before further flight, remove from service main rotor blade spindles P/N's S6110-23325-1, S6110-23325-2, and S6112-23025-1, serial numbers AX51, AX54, F2148, F2444, F2485, F2207, F1406, F1416, F1415, F1399, B-35, and F2451.