78-11-02 R1: Rotor Blade Straps

78-11-02 R1 BELL HELICOPTER TEXTRON, INC.: Amendment 39-3221 as amended by Amendment 39-6069. Applies to Model 206A, 206A-1, 206B, 206B-1, 206L, 206L-1, and 206L-3 helicopters certificated in any category. (Airworthiness Docket No. 76-ASW-41) Compliance is required within the next 6 calendar months after effective date of this AD, unless already accomplished. To prevent M/R blades from departing the helicopter, accomplish the following: (a) For straps with less than 550 hours' total time in service on the effective date of this AD, accomplish the following prior to attaining 600 hours' total time in service or January 1, 1979, whichever occurs first. (1) Remove each strap having the applicable part numbers, if installed, and remove associated inboard strap fittings, P/N 206-010-155-11 and -15, if installed. (2) Install straps, P/N 206-011-147-1 or -5, and inboard strap fittings, P/N 206-011-140-1, on Models 206A, 206B, 206A-1, and 206B-1 or P/N 206-011-147-3 or -7 straps on Model 206L in accordance with the applicable Model 206 Maintenance and Overhaul Instructions or in accordance with equivalent FAA approved instructions. (b) For straps with 550 hours' or more total time in service on the effective date of this AD, accomplish paragraphs (a) (1) and (a) (2) of this AD within the next 50 hours' time in service or January 1, 1979, whichever occurs first, unless already accomplished. (c) The retirement time of the tension-torsion straps, Part Numbers 206-010-105-3, 206-010-105-5, and 206-011-127-1, is reduced from 1,200 to 600 hours' time in service. These straps must be retired from service by January 1, 1989, regardless of time in service. The inboard strap fittings, P/N's 206-010-155-11 and -15, must be removed from service as noted in paragraph (a) (1) of this AD. Replacement tension-torsion straps, P/N's 206-011-147-001, -003, -005, -007, and 206-011-154-101 and -103, have a 1,200 hour time in service life or 2-year calendar life after installation, whichever occurs first. (d) An alternate method of compliance which provides an equivalent level of safety with this AD may be used when approved by the Manager, Helicopter Certification Branch, Federal Aviation Administration, Fort Worth, Texas 76193-0170. This amendment amends Amendment 39-3221; AD No. 78-11-02 (43 FR 22340). This amendment, 39-6069, becomes effective December 15, 1988.