# AD 86-09-03 R1: Tail Rotor Blades

- Type: Airworthiness directive
- Status: Current
- Products: Airbus Helicopters Deutschland MBB-BK 117 A-3
- Effective: May 16, 1987
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Rotorcraft
- Amendment: 39-5542
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/84C935152E1CBA6786256A4E00562F76.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/86-09-03-R1

## The airworthiness directive

86-09-03 R1 MESSERSCHMITT-BOLKOW-BLOHM: Amendment 39-5294 as amended by Amendment 39-5542. Applies to Model BK 117A-3 helicopters, certificated in any category that are equipped with tail rotor blades P/N 117-31742, S/N's 63 up to and including 82.

Compliance is required as indicated, unless previously accomplished.

To detect or prevent possible in-flight separation of a tail rotor blade leading edge erosion protective shell or plate, accomplish the following:

  (a) For tail rotor blades with less than 5 hours time in service on the effective date of this AD, remove blades before further flight.

  (b) For tail rotor blades with 5 or more hours time in service on the effective date of this AD, before each flight, inspect the erosion protective shell and plate for separation in accordance with the MBB BK-117 maintenance manual, Section 34-2, paragraph 2a or b.

  (c) If bonding separation exceeds permissible limits stated in Section 34-2, paragraph 2c of the maintenance manual, remove the affected blade before further flight.

  (d) Upon request, an equivalent means of compliance with this AD may be used when approved by the Manager, Aircraft Certification Office, FAA, Europe, Africa, and Middle East Office, c/o American Embassy, Brussels, Belgium, APO NY 09667-1011.

  (e) The aircraft may be flown in accordance with FAR Sections 21.197 and 21.199 to a base where the tail rotor blades may be replaced.

  (f) A tail rotor blade with leading edge that was inspected and/or rebonded per MBB Service Bulletin No. SB-MBB-BK117-30-1, Revision 1, dated June 12, 1986, and determined serviceable is no longer subject to this AD.

The procedures shall be done in accordance with Section 34-2, paragraphs 2a, b, and c of the MBB BK-117 maintenance manual, undated, and MBB SB No. MBB-BK-117-30-1, Revision 1, dated June 12, 1986. This incorporation by reference was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a)(1).Copies may be obtained from MBB Helicopter Corporation, P.O. Box 2349, West Chester, Pennsylvania 19280. Copies may be inspected at the Office of the Regional Counsel, FAA, Southwest Region, 4400 Blue Mound Road, Fort Worth, Texas, or at the Office of the Federal Register, 1100 L Street, NW., Room 8401, Washington, D.C.

Amendment 39-5294 became effective May 20, 1986. This amendment 39-5542 becomes effective May 16, 1987.

## Affected data sheets (1) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS H13EU](https://openairdocs.org/tcds/H13EU): Airbus Helicopters Deutschland GmbH (AHD); names 1 of 9 models: MBB-BK 117 A-3

## Registered aircraft it may apply to (OpenAirDocs)

No registered aircraft matched the models it names.

Its text cites no advisory circulars or STCs.

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