# AD 89-02-02: Antiskid Valve & Brake Metering Valve - Type: Airworthiness directive - Status: Current - Products: Boeing 757-200 Series, 757-200CB Series, 757-200PF Series and 757-300 Series - Effective: February 8, 1989 - Superseded by: Nothing supersedes this AD - Product type: Aircraft, Large airplane - Amendment: 39-6100 - Registered aircraft: 270 may be affected, by airframe or engine model (OpenAirDocs) - FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/D0413E8A3106E41B8625695A0070FA16.0001 - DRS record last changed: May 30, 2024 - Page: https://openairdocs.org/ad/89-02-02 ## The airworthiness directive 89-02-02 BOEING: Amendment 39-6100. Applicability: Model 757 series airplanes, Group 1 and Group 2, as listed in Boeing Alert Service Bulletin 757-32A0081, dated June 24, 1988, certificated in any category. Compliance: Required within the next 120 days after the effective date of this AD, unless previously accomplished. To prevent the loss of airplane braking due to a single hydraulic failure, accomplish the following: A. Inspect Group 1 and 2 airplanes left and right alternate antiskid valve module return ports for proper check valve configuration, and correct, if necessary, in accordance with Boeing Alert Service Bulletin 757-32A0081, dated June 24, 1988. B. On Group 1 airplanes, remove the reducer unions installed in the left and right alternate brake metering valve module return ports and install check valves, in accordance with Boeing Alert Service Bulletin 757-32A0081, dated June 24, 1988. C. An alternate means of compliance or adjustment ofthe compliance time, which provides an acceptable level of safety, may be used when approved by the Manager, Seattle Aircraft Certification Office, FAA, Northwest Mountain Region. NOTE: The request should be forwarded through an FAA Principal Maintenance Inspector (PMI), who may add any comments and then send to the Manager, Seattle Aircraft Certification Office. D. 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 the inspections and/or modifications required by 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 Airplanes, P.O. Box 3707, Seattle, Washington 98124. These documents may be examined at the FAA, Northwest Mountain Region, 17900 Pacific Highway South, Seattle, Washington, or Seattle Aircraft Certification Office, FAA, Northwest Mountain Region, 9010 East Marginal Way South, Seattle, Washington. This amendment (39-6100, AD 89-02-02) becomes effective February 8, 1989. ## Affected data sheets (1) (OpenAirDocs) The type certificate data sheets whose models the AD names. - [TCDS A2NM](https://openairdocs.org/tcds/A2NM): The Boeing Company; names 4 of 4 models: 757-200CB Series, 757-200PF Series, 757-300 Series, 757-200 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: 270 (270 by airframe model, 0 by engine model) - Makers: Boeing 270 Models with the most aircraft: - [Boeing 757-232](https://openairdocs.org/model/boeing-757-232): 63 aircraft (airframe model) - [Boeing 757-224](https://openairdocs.org/model/boeing-757-224): 40 aircraft (airframe model) - [Boeing 757-222](https://openairdocs.org/model/boeing-757-222): 38 aircraft (airframe model) - [Boeing 757-223](https://openairdocs.org/model/boeing-757-223): 23 aircraft (airframe model) - [Boeing 757-236](https://openairdocs.org/model/boeing-757-236): 20 aircraft (airframe model) - [Boeing 757-251](https://openairdocs.org/model/boeing-757-251): 18 aircraft (airframe model) - [Boeing 757-351](https://openairdocs.org/model/boeing-757-351): 16 aircraft (airframe model) - [Boeing 757-231](https://openairdocs.org/model/boeing-757-231): 13 aircraft (airframe model) - [Boeing 757-324](https://openairdocs.org/model/boeing-757-324): 9 aircraft (airframe model) - [Boeing 757-200 SERIES](https://openairdocs.org/model/boeing-757-200-series): 7 aircraft (airframe model) - [Boeing 757-204](https://openairdocs.org/model/boeing-757-204): 6 aircraft (airframe model) - [Boeing 757-225](https://openairdocs.org/model/boeing-757-225): 5 aircraft (airframe model) - [Boeing 757-230](https://openairdocs.org/model/boeing-757-230): 4 aircraft (airframe model) - [Boeing 757-258](https://openairdocs.org/model/boeing-757-258): 3 aircraft (airframe model) - [Boeing 757-256](https://openairdocs.org/model/boeing-757-256): 3 aircraft (airframe model) - [Boeing 757-260PF](https://openairdocs.org/model/boeing-757-260pf): 2 aircraft (airframe model) All 16 models: https://openairdocs.org/ad/89-02-02/models.md Every aircraft: https://openairdocs.org/ad/89-02-02/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.