AD 81-12-03

81-12-03 BELL HELICOPTER TEXTRON (BHT): Amendment 39-4125. Applies to all Model 214 series helicopters certified in all categories (Airworthiness Docket No. 81-ASW- 24).

To prevent possible failure of main rotor spindle attachment pin retention bolts, P/N EWB26-10H90, accomplish the following:

(a) Unless Bell Helicopter Textron Alert Service Bulletin 214-81-17 has been previously complied with, within the next 50 hours' time in service after the effective date of this AD:

(1) Remove and inspect each of the four main rotor spindle attachment pin retention bolts, P/N EWB26-10H90, for evidence of corrosion.

(2) Replace all bolts exceeding 1,200 hours' time in service or showing evidence of corrosion.

(3) When installing the bolts, assure that each bolt is installed using corrosion prevention compound MIL-C-16173 grade 1 or 2 or equivalent on the shank of the bolt. Wipe threads clean prior to installing the nuts. Torque the nut to 150 foot-pounds.

(b) Bolts, P/N EWB26-10H90, now have a 1,200 hour retirement. Record the 1,200 hour retirement life in the aircraft records.

(c) Any equivalent method of compliance with this AD must be approved by the Chief, Engineering and Manufacturing Branch, Flight Standards Division, Southwest Region, Federal Aviation Administration.

(d) In accordance with FAR 21.197, flight is permitted to a base where the inspection and repairs required by this AD may be accomplished.

This amendment becomes effective June 11, 1981.