# AD 91-25-03 R1: Main Landing Gear Brakes

- Type: Airworthiness directive
- Status: Current
- Products: Boeing DC-9-11, DC-9-12, DC-9-13, DC-9-14, DC-9-15, DC-9-15F, DC-9-21, DC-9-31, DC-9-32, DC-9-32 (VC-9C), DC-9-32F, DC-9-32F (C-9A) and 6 more
- Effective: December 31, 1991
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Large airplane
- Amendment: 39-8136
- Docket: 91-NM-78-AD
- Registered aircraft: 13 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/F1B2713C0F6D27D886256A080064D368.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/91-25-03-R1

## The airworthiness directive

91-25-03 R1 MCDONNELL DOUGLAS: Amendment 39-8136. Docket Number 91-NM-78-AD.

Applicability: Model DC-9 series, including C-9 (military), airplanes equipped with Aircraft Braking System (ABS) brake part numbers identified in paragraph (a), of this AD, certificated in any category.

Compliance: Required as indicated, unless previously accomplished.

To prevent the loss of main landing gear braking effectiveness, accomplish the following:

  (a) Within 270 days after the effective date of this AD, inspect the landing gear brakes, having brake numbers listed below, for wear. Any brake worn more than the maximum wear limit specified below must be replaced, prior to further flight, with a brake within these limits.

Series Airplane ABS Brake Part Number Maximum Wear Limit (inches) DC-9-10 9560746A 0.3

B9560746A 0.3

9560743 0.3

A9560743 0.3

B9560743 0.3

DC-9-20/30 9560786 0.3

A9560786 0.3

B9560786 0.3DC-9-30 9560955 0.3

9560788 0.3

A9560788 0.3

B9560788 0.3

9560788-2/-3/-5/-6 0.3

9560788-7 0.7

DC-9-30/40/50 B9560861 0.3

9560861-1 0.2

9560861-2 0.3

9560861-3 0.8

  (b) Within 270 days after the effective date of this AD, incorporate the maximum brake wear limits specified in paragraph (a) of this AD into the FAA-approved maintenance inspection program.

  (c) 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, Los Angeles 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, Los Angeles ACO.

  (d) 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 therequirements of this AD.

  (e) This amendment (39-8136, AD 91-25-03 R1) is effective on December 31, 1991.

## Affected data sheets (1) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS A6WE](https://openairdocs.org/tcds/A6WE): The Boeing Company; names 15 of 25 models: DC-9-12, DC-9-15F, DC-9-41, DC-9-13, DC-9-34F, DC-9-33F, DC-9-11, DC-9-51…

## 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: 13 (13 by airframe model, 0 by engine model)
- Makers: Mcdonnell Douglas 8, Douglas 5

Models with the most aircraft:

- [Mcdonnell Douglas DC-9-15F](https://openairdocs.org/model/mcdonnell-douglas-dc-9-15f): 3 aircraft (airframe model)
- [Mcdonnell Douglas DC-9-33F](https://openairdocs.org/model/mcdonnell-douglas-dc-9-33f): 3 aircraft (airframe model)
- [Douglas DC9-15](https://openairdocs.org/model/douglas-dc9-15): 1 aircraft (airframe model)
- [Douglas DC-9-15F](https://openairdocs.org/model/douglas-dc-9-15f): 1 aircraft (airframe model)
- [Douglas DC-9-21](https://openairdocs.org/model/douglas-dc-9-21): 1 aircraft (airframe model)
- [Douglas DC-9-32F](https://openairdocs.org/model/douglas-dc-9-32f): 1 aircraft (airframe model)
- [Mcdonnell Douglas DC-9-32](https://openairdocs.org/model/mcdonnell-douglas-dc-9-32): 1 aircraft (airframe model)
- [Mcdonnell Douglas DC-9-32F](https://openairdocs.org/model/mcdonnell-douglas-dc-9-32f): 1 aircraft (airframe model)
- [Douglas DC-9-33F](https://openairdocs.org/model/douglas-dc-9-33f): 1 aircraft (airframe model)

All 9 models: https://openairdocs.org/ad/91-25-03-R1/models.md
Every aircraft: https://openairdocs.org/ad/91-25-03-R1/aircraft.md

Its text cites no advisory circulars or STCs.

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