# AD 91-10-09: Vertical Stabilizer

- Type: Airworthiness directive
- Status: Current
- Products: Boeing 767-200 Series, 767-300 Series and 767-300F Series
- Effective: June 17, 1991
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Large airplane
- Amendment: 39-6993
- Docket: 90-NM-238-AD
- Registered aircraft: 402 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/0CA08BED4EEAC466862569610072D198.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/91-10-09

## The airworthiness directive

91-10-09 BOEING: Amendment 39-6993. Docket No. 90-NM-238-AD.

Applicability: Model 767 series airplanes, line number 300 through 307, certificated in any category.

Compliance: Required as indicated, unless previously accomplished.

To prevent structural failure of the vertical stabilizer from overpressurization in the event of a rupture of the fuselage under the dorsal fin, accomplish the following:

A. Within the next 18 months after the effective date of this amendment, install a cover plate and a panel assembly over the lightening and access holes in the vertical stabilizer forward closure rib, in accordance with Boeing Alert Service Bulletin 767-55A0007, dated June 22, 1989, or Revision 1, dated May 24, 1990.

B. An alternative method of compliance or adjustment of the compliance time, which provides an acceptable level of safety, may be used when approved by the Manager, Seattle Aircraft Certification Office (ACO), FAA, Transport Airplane Directorate.NOTE: The request should be forwarded through an FAA Principal Maintenance Inspector, who may concur or comment and then send it to the Manager, Seattle ACO.

C. Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate airplanes to a base in order to comply with the requirements of this AD.

All persons affected by this directive who have not already received the appropriate service documents from the manufacturer may obtain copies upon request to Boeing Commercial Airplane Group, P.O. Box 3707, Seattle, Washington 98124. These documents may be examined at the FAA, Northwest Mountain Region, Transport Airplane Directorate, 1601 Lind Avenue S.W., Renton, Washington.

This amendment (39-6993, AD 91-10-09) becomes effective on June 17, 1991.

## 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/91-10-09/models.md
Every aircraft: https://openairdocs.org/ad/91-10-09/aircraft.md

Its text cites no advisory circulars or STCs.

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