# AD 86-04-08: Counterbalance Gearbox Assembly - Type: Airworthiness directive - Status: Current - Products: Boeing 767-200 Series, 767-300 Series and 767-300F Series - Effective: March 27, 1986 - Superseded by: Nothing supersedes this AD - Product type: Aircraft, Large airplane - Amendment: 39-5238 - Registered aircraft: 402 may be affected, by airframe or engine model (OpenAirDocs) - FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/280496EB845F0206862568AA00661A1C.0001 - DRS record last changed: May 30, 2024 - Page: https://openairdocs.org/ad/86-04-08 ## The airworthiness directive 86-04-08 BOEING: Amendment 39-5238. Applies to Model 767 series airplanes, as specified in Boeing Service Bulletin 767-52-0029 dated August 2, 1985, certificated in any category. To assure proper entry/service door operation during emergency evacuation, accomplish the following within nine months after the effective date of this AD, unless previously accomplished: A. Modify the counterbalance gearbox assemblies in accordance with Boeing Service Bulletin 767-52-0029 dated August 2, 1985, or later FAA-approved revisions. B. An alternate means of compliance which provides an acceptable level of safety may be used when approved by the Manager, Seattle Aircraft Certification Office, FAA, Northwest Mountain Region. C. Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate airplanes to a base for the accomplishment of inspections and/or modifications required by this AD. All persons affected by this proposal who have not alreadyreceived copies of the manufacturer's service bulletin may obtain copies upon request from the Boeing Commercial Airplane Company, P.O. Box 3707, Seattle, Washington 98124. This document may be examined at the FAA, Northwest Mountain Region, 17900 Pacific Highway South, Seattle, Washington, or the Seattle Aircraft Certification Office, 9010 East Marginal Way South, Seattle, Washington. This amendment becomes effective March 27, 1986. ## Affected data sheets (1) (OpenAirDocs) The type certificate data sheets whose models the AD names. - [TCDS A1NM](https://openairdocs.org/tcds/A1NM): The Boeing Company; names 3 of 5 models: 767-300 Series, 767-200 Series, 767-300F Series ## Registered aircraft it may apply to (OpenAirDocs) Matched by airframe and engine model; the AD's applicability may narrow it by serial number, part number or equipment. - Aircraft: 402 (402 by airframe model, 0 by engine model) - Makers: Boeing 402 Models with the most aircraft: - [Boeing 767-300F](https://openairdocs.org/model/boeing-767-300f): 169 aircraft (airframe model) - [Boeing 767-332](https://openairdocs.org/model/boeing-767-332): 46 aircraft (airframe model) - [Boeing 767-322](https://openairdocs.org/model/boeing-767-322): 36 aircraft (airframe model) - [Boeing 767-323](https://openairdocs.org/model/boeing-767-323): 27 aircraft (airframe model) - [Boeing 767-338](https://openairdocs.org/model/boeing-767-338): 13 aircraft (airframe model) - [Boeing 767-316](https://openairdocs.org/model/boeing-767-316): 12 aircraft (airframe model) - [Boeing 767-346](https://openairdocs.org/model/boeing-767-346): 11 aircraft (airframe model) - [Boeing 767-281](https://openairdocs.org/model/boeing-767-281): 9 aircraft (airframe model) - [Boeing 767-381](https://openairdocs.org/model/boeing-767-381): 8 aircraft (airframe model) - [Boeing 767-232](https://openairdocs.org/model/boeing-767-232): 6 aircraft (airframe model) - [Boeing 767-319](https://openairdocs.org/model/boeing-767-319): 6 aircraft (airframe model) - [Boeing 767-306](https://openairdocs.org/model/boeing-767-306): 5 aircraft (airframe model) - [Boeing 767-224](https://openairdocs.org/model/boeing-767-224): 5 aircraft (airframe model) - [Boeing 767-300](https://openairdocs.org/model/boeing-767-300): 5 aircraft (airframe model) - [Boeing 767-316F](https://openairdocs.org/model/boeing-767-316f): 5 aircraft (airframe model) - [Boeing 767-336](https://openairdocs.org/model/boeing-767-336): 4 aircraft (airframe model) - [Boeing 767-223](https://openairdocs.org/model/boeing-767-223): 3 aircraft (airframe model) - [Boeing 767-231](https://openairdocs.org/model/boeing-767-231): 3 aircraft (airframe model) - [Boeing 767-304](https://openairdocs.org/model/boeing-767-304): 3 aircraft (airframe model) - [Boeing 767-324](https://openairdocs.org/model/boeing-767-324): 3 aircraft (airframe model) All 36 models: https://openairdocs.org/ad/86-04-08/models.md Every aircraft: https://openairdocs.org/ad/86-04-08/aircraft.md Its text cites no advisory circulars or STCs. --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.