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97-23-07: Record New Life Limit Of Clutch

FAA order 97-23-07 is an airworthiness directive in force since December 10, 1997. The FAA's subject line: Record New Life Limit Of Clutch. It names Airbus Helicopters MBB-BK 117 C-1: about 9 aircraft on the U.S. register today, though an order usually covers particular versions or serial numbers rather than every one. System: other and general.

What it applies to as the FAA lists it

Kind of product
Aircraft
Makes
Airbus Helicopters Deutschland GmbH
Models
MBB-BK 117 A-1, MBB-BK 117 A-3, MBB-BK 117 A-4, MBB-BK 117 B-1, MBB-BK 117 B-2, MBB-BK 117 C-1
On this site
Airbus Helicopters MBB-BK 117 C-1 9 registered

Dates and paperwork

In force since
December 10, 1997
Docket
96-SW-23-AD
Status
Current
The FAA's document
Read the order on the FAA's site

The FAA's summary their words, unchanged

This amendment adopts a new airworthiness directive (AD), applicable to Eurocopter Deutschland GmbH (Eurocopter) Model MBB-BK 117 A-1, A-3, A-4, B-1, B-2, and C-1 helicopters, that establishes a new retirement life for the clutch and requires an entry into the Accessory Replacement Record indicating the new life limit. This amendment is prompted by a recalculation of life limitations by the part manufacturer, Warner Electric. The clutch manufacturer used the airframe load spectrum to establish the new life limit of 3,600 hours time-in-service (TIS). The actions specified by this AD are intended to prevent failure of the clutch, loss of power to the main rotor and a subsequent forced landing of the helicopter.

The order itself the regulatory text, as published

Show the full text (3,165 characters)
97-23-07 EUROCOPTER DEUTSCHLAND GmbH: Amendment 39-10195. Docket No. 96-SW-23-AD. Applicability: Model MBB-BK 117 A-1, A-3, A-4, B-1, and B-2 helicopters, serial numbers (S/N) 7001 through 7250, and Model MBB-BK 117 C-1 helicopters, S/N 7500 through 7520, with clutch, part number (P/N) 4639302044 or P/N CL42067-1, installed, certificated in any category. NOTE 1: This AD applies to each helicopter identified in the preceding applicability provision, regardless of whether it has been modified, altered, or repaired in the area subject to the requirements of this AD. For helicopters that have been modified, altered, or repaired so that the performance of the requirements of this AD is affected, the owner/operator must use the authority provided in paragraph (d) to request approval from the FAA. This approval may address either no action, if the current configuration eliminates the unsafe condition, or different actions necessary to address the unsafe condition describedin this AD. Such a request should include an assessment of the effect of the changed configuration on the unsafe condition addressed by this AD. In no case does the presence of any modification, alteration, or repair remove any helicopter from the applicability of this AD. Compliance: Required as indicated, unless accomplished previously. To prevent failure of the clutch, loss of power to the main rotor and a subsequent forced landing of the helicopter, accomplish the following: (a) Within 30 hours time-in-service (TIS) after the effective date of this AD, make an entry into the Accessory Replacement Record to reflect a new life limit of 3,600 hours TIS for the clutch, P/N 4639302044 or P/N CL42067-1. (b) Remove the clutch, P/N 4639302044 or P/N CL42067-1, from service on or before reaching 3,600 hours TIS. This AD revises the Airworthiness Limitations section of the maintenance manual by establishing a new retirement life for the clutch, P/N 4639302044 or P/N CL42067-1, of 3,600 hours TIS. (c) Replacement of the clutch, P/N 4639302044 or P/N CL42067-1, with a clutch, P/N 4639202011, constitutes a terminating action for the requirements of this AD. (d) An alternative method of compliance or adjustment of the compliance time that provides an acceptable level of safety may be used if approved by the Manager, Rotorcraft Standards Staff, Rotorcraft Directorate, FAA. Operators shall submit their requests through an FAA Principal Maintenance Inspector, who may concur or comment and then send it to the Manager, Rotorcraft Standards Staff. NOTE 2: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Rotorcraft Standards Staff. (e) Special flight permits may be issued in accordance with sections 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 21.197 and 21.199) to operate the helicopter to a location where the requirements of this AD can beaccomplished. NOTE 3: The subject of this AD is addressed in Luftfahrt-Bundesamt (Germany) AD 95-242, dated June 13, 1995. (f) This amendment becomes effective on December 10, 1997.

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Source: FAA Dynamic Regulatory System, airworthiness directives. The FAA's document is the authority; the register counts are this site's, from the FAA register of November 6, 2026. Connections as data: /graph/directive/97-23-07.json · aircraft systems.