89-20-03 R1 SCHWEIZER AIRCRAFT CORPORATION (HUGHES HELICOPTERS, Inc.): Amendment 39-6540 as revised by Amendment 39-6863. Docket No. 89-ASW-41.
Applicability: All Model 269 series helicopters, certified in any category, equipped with 269A6035 series tail rotor blades manufactured before September 15, 1989.
Compliance: Required as indicated, unless already accomplished.
To prevent the loss of the abrasion strips on the tail rotor blades with subsequent loss of tail rotor control, accomplish the following:
(a) Install rivets in the tail rotor blades as follows:
(1) Prior to further flight after the effective date of this AD, modify the affected tail rotor blades with the following serial numbers (S/N) in accordance with the procedures detailed in Appendix 1 of this AD:
R0056
S524
S584
S640-S644
R0086
S534
S586
S646
R1059
S538
S588
S648-S650
R1066
S539
S589-S594
S653
R1560
S544
S596
S654
R1922
S546
S598-S603
S657
R3296S547
S605
S660-S662
R3314
S549
S607
S664-S666
R3330
S550
S608
S668
R3349
S553
S611-S620
S670-S672
S21
S556-S563
S623-S626
S675-S677
S431
S565
S631-S633
S679-S682
S513
S566
5637
S684-S688
S515
S568-S571
S638
S691-S694
S518
S573
S521
S576-S582
(2) Within the next 100 hours' time in service after the effective date of this AD, modify all tail rotor blades, whether manufactured by Schweizer or Hughes, except those listed in paragraph (a)(1) in accordance with procedures described in Appendix I of this AD.
(b) Before the first flight of each day, visually check the abrasion strip of these blades for any evidence of cracking or chipping along the entire abrasion strip/airfoil bond line and the blade tip.
(c) If, during the check required by paragraph (b), cracking or chipping is observed, inspect the bond line for bond separation using a 10 power or higher magnifying glass. If evidence of debonding along the abrasion strip/bond line or blade tip is detected, inspect the tail rotor blade using dye penetrant or equivalent inspection method and tap test prior to further flight in accordance with Appendix I of this AD.
(d) Remove from service, prior to further flight, any rotor blade found to contain bond separation.
(e) The visual check required by paragraph (b) of this AD may be performed by the pilot and must be recorded in accordance with FAR Section 43.9.
NOTE: The pilot, when complying, must make appropriate entries and the record must be maintained in accordance with FAR Section 91.173 or 135.439.
(f) Aircraft may be ferried in accordance with the provisions of FAR Section 21.197 and 21.199 to a base where the requirements of this AD can be accomplished.
(g) Alternative inspections, modifications, or other actions which provide an equivalent level of safety may be used when approved by the Manager, New York Aircraft Certification Office, FAA, 181 South Franklin Avenue, Room 202, Valley Stream, NY.
NOTE: Blades modified to Schweizer Installation Instructions No. CKP-C-40, Kit No. SCA-269-K-056, dated August 31, 1989, or Schweizer Service Information Notice No. N- 183.3, September 15, 1989, Part III, comply with paragraph (a) of this AD.
(h) Tail rotor blades manufactured by Schweizer with a bond date on or after September 15, 1989, shown on the identification plate located on the inboard end of the blade, are exempt from the requirements of this AD.
NOTE: Appendix I, which is not reprinted in this AD, includes material from Schweizer Aircraft Corporation Service Information Notice (S/N) N-183.3, dated September 15, 1989. A copy of the service information may be obtained from Schweizer Aircraft Corporation, P.O. Box 147, Elmira, New York 14902.
Airworthiness Directive 89-20-03 R1 supersedes AD 87-22-07, Amendment 39-5730 (52 FR 4155, October 29, 1987).
Airworthiness Directive 89-20-03 R1 amends AD 89-20-03, Amendment 39-6540(55 FR 10228, March 20, 1990) which was the Final Rule of Priority Letter AD 89-20-03 issued on September 28, 1990.
This amendment (39-6863, AD 89-20-03 R1) becomes effective on February 22, 1991.