91-23-12: Main Landing Gear Braking Effectiveness
FAA order 91-23-12 is an airworthiness directive in force since December 9, 1991. The FAA's subject line: Main Landing Gear Braking Effectiveness. System: landing gear.
What it applies to as the FAA lists it
- Kind of product
- Aircraft
- Makes
- Lockheed Martin Corporation
- Models
- L-1011-385-1, L-1011-385-1-14, L-1011-385-1-15, L-1011-385-3
Dates and paperwork
- In force since
- December 9, 1991
- Docket
- 91-NM-77-AD
- Status
- Current
- The FAA's document
- Read the order on the FAA's site
The order itself the regulatory text, as published
Show the full text (2,931 characters)
91-23-12 LOCKHEED: Amendment 39-8081. Docket No. 91-NM-77-AD.
Applicability: Model L-1011 series airplanes, equipped with BFGoodrich 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 180 days after the effective date of this AD, inspect the brake part numbers shown 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 this limit.
Type Certificated
Model Designation
Common Model
Designation
Maximum
GTOW
Brake
Part No.
Maximum Wear
Limit (inches)
L-1011-385-1
(-1)
430,000
2-1195-1
2.10
(-1)
430,000
2-1195-5
2.10
(-1)
430,000
2-1195-6
2.10
(-1)
430,000
2-1195-7
2.10
(-1)
430,000
2-1195-8
2.10
(-1)
430,000
2-1367
3.00
(-1)
430,000
2-1367-1
3.00
(-1)
430,000
2-1367-2
3.00
(-40)
440,000
2-1195-1
2.10
(-40)
440,000
2-1195-5
2.10
(-40)
440,000
2-1195-6
2.10
(-40)
440,000
2-1195-7
2.10
(-40)
440,000
2-1195-8
2.10
(-40)
440,000
2-1367
3.00
(-40)
440,000
2-1367-1
3.00
(-40)
440,000
2-1367-2
3.00
(-50)
450,000
2-1367-3
2.60
(-50)
450,000
2-1367-4
2.60
(-50)
450,000
2-1367-5
2.60
L-1011-385-1-14
(-100,-150,-200)
466,000
2-1367-3
2.60
(-100,-150,-200)
to
2-1367-4
2.60
(-100,-150,-200)
474,000
2-1367-5
2.60
(-250)
510,000
2-1367
3.00
(-250)
510,000
2-1367-1
3.00
(-250)
510,000
2-1367-2
3.00
L-1011-385-1-15
(-100,-150,-200)
466,000
2-1367-3
2.60
(-100,-150,-200)
to
2-1367-4
2.60
(-100,-150,-200)
474,000
2-1367-5
2.60
(-250)
510,000
2-1367
3.00
(-250)
510,000
2-1367-1
3.00
(-250)510,000
2-1367-2
3.00
L-1011-385-3
(-500)
496,000
2-1367
3.00
(-500)
to
2-1367-1
3.00
(-500)
516,000
2-1367-2
3.00
NOTE: Lockheed Service Bulletin 093-32-253, dated March 29, 1991, contains additional information concerning Model L-1011 brake configurations.
(b) Within 180 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 the requirements of this AD.
This amendment (39-8081, AD 91-23-12) becomes effective on December 9, 1991.
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/91-23-12.json · aircraft systems.