# AD 91-07-19: Structural Modifications

- Type: Airworthiness directive
- Status: Current
- Products: Boeing 707-100 Long Body, 707-100B Long Body, 707-100B Short Body, 707-200, 707-300 Series, 707-300B Series, 707-300C Series, 707-400 Series, 720 Series and 720B Series
- Effective: April 29, 1991
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Large airplane
- Amendment: 39-6926
- Docket: 89-NM-263-AD
- Registered aircraft: 6 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/CA172405CD988581862569610072CAA4.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/91-07-19

## The airworthiness directive

91-07-19 BOEING: Amendment 39-6926. Docket No. 89-NM-263-AD.

Applicability: Model 707/720 series airplanes, listed in Boeing Document No. D6-54996, Revision B, dated December 11, 1990, certificated in any category.

Compliance: Required as indicated, unless previously accomplished.

To prevent structural failure, accomplish the following:

A. Accomplish the structural modifications listed in Section 3 of Boeing Document No. D6- 54996, "Aging Airplane Service Bulletin Structural Modification Program-Model 707/720," Revision B, dated December 11, 1990, at the earlier of the following times:

1. Prior to reaching the incorporation thresholds listed in the Boeing Document or within the next 4 years after the effective date of this AD, whichever occurs later; or

2. Prior to reaching the incorporation thresholds specified as calendar dates in the Boeing Document.

NOTE: The modifications required by this paragraph do not terminate the inspection requirements of any other AD unless that AD specifies that any such modification constitutes terminating action for the inspection requirements.

B. An alternate means 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, Northwest Mountain Region.

NOTE: The request should be submitted directly to the Manager, Seattle ACO, and a copy sent to the cognizant FAA Principal Inspector (PI). The PI will then forward comments or concurrence to the 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.

The modifications shall be done in accordance with Boeing Document No. D6-54996, "Aging Airplane Service Bulletin Structural Modification Program - Model 707/720," Revision B, dated December 11, 1990, which incorporates the following list of effective pages:

TABLE OF EFFECTIVE PAGES

Page Number Revision Number Date Page a Revision B December 11, 1990 Page b Initial Release November 7, 1989 Pages c.1-d.5 Revision B December 11, 1990 Page e Revision A September 14, 1990 Pages f-1.0.1 Initial Release November 7, 1989 Page 1.0.2 Revision B December 11, 1990 Pages 1.0.3-2.0.2 Initial Release November 7, 1989 Pages 3.0.1-3.1.8 Revision B December 11, 1990 Page 3.1.9 Initial Release November 7, 1989 Pages 3.1.10-3.4.1 Revision B December 11, 1990 Pages 3.4.2-3.6.1 Initial Release November 7, 1989 Pages 4.0.1-5.1.5 Revision A September 14, 1990 Pages 5.1.6-5.1.8 Revision B December 11, 1990 Pages 5.1.9-5.1.11 Revision A September 14, 1990

Boeing Document No. DC-54996, "Aging Airplane Service Bulletin Structural Modification Program - Model 707/720," was issued by The Boeing Company on November 7, 1989. The Boeing Company has made two revisions to the November 7, 1989, document: "Revision A" was issued on September 14, 1990, and "Revision B" was issued on December 11, 1990. The preceding Table of Effective Pages depicts the original and revised pages that have received incorporation by reference approval.

This incorporation by reference was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR Part 51. Copies may be obtained from Boeing Commercial Airplane Group, P.O. Box 3707, Seattle, Washington 98124. Copies may be inspected at the FAA, Northwest Mountain Region, Transport Airplane Directorate, 1601 Lind Avenue S.W., Renton, Washington; or at the Office of the Federal Register, 1100 L Street S.W., Room 8401, Washington, D.C.

This amendment (39-6926, AD 91-07-19) becomes effective on April 29, 1991.

## Affected data sheets (3) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS 4A21](https://openairdocs.org/tcds/4A21): The Boeing Company; names 4 of 4 models: 707-100B Short Body, 707-200, 707-100 Long Body, 707-100B Long Body
- [TCDS 4A26](https://openairdocs.org/tcds/4A26): The Boeing Company; names 4 of 4 models: 707-300B Series, 707-400 Series, 707-300 Series, 707-300C Series
- [TCDS 4A28](https://openairdocs.org/tcds/4A28): The Boeing Company; names 2 of 2 models: 720B Series, 720 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: 6 (6 by airframe model, 0 by engine model)
- Makers: Boeing 6

Models with the most aircraft:

- [Boeing 707-338C](https://openairdocs.org/model/boeing-707-338c): 2 aircraft (airframe model)
- [Boeing 707-368C](https://openairdocs.org/model/boeing-707-368c): 1 aircraft (airframe model)
- [Boeing 707-321B](https://openairdocs.org/model/boeing-707-321b): 1 aircraft (airframe model)
- [Boeing 707-323B](https://openairdocs.org/model/boeing-707-323b): 1 aircraft (airframe model)
- [Boeing 707-351B](https://openairdocs.org/model/boeing-707-351b): 1 aircraft (airframe model)

All 5 models: https://openairdocs.org/ad/91-07-19/models.md
Every aircraft: https://openairdocs.org/ad/91-07-19/aircraft.md

Its text cites no advisory circulars or STCs.

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