# AD 90-25-11: In-Flight Spoiler Lockout Mechanism - Type: Airworthiness directive - Status: Current - Products: Boeing DC-9-81 (MD-81), DC-9-82 (MD-82), DC-9-83 (MD-83), DC-9-87 (MD-87) and MD-88 - Effective: December 17, 1990 - Superseded by: Nothing supersedes this AD - Product type: Aircraft, Large airplane - Amendment: 39-6819 - Docket: 90-NM-228-AD - Registered aircraft: 100 may be affected, by airframe or engine model (OpenAirDocs) - FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/715118C6EE47DE6C86256A080064B282.0001 - DRS record last changed: May 30, 2024 - Page: https://openairdocs.org/ad/90-25-11 ## The airworthiness directive 90-25-11 McDONNELL DOUGLAS: Amendment 39-6819. Docket No. 90-NM-228-AD. Applicability: Model DC-9-80 series airplanes and Model MD-88 airplanes; Fuselage Numbers 1606, 1620, 1623, 1624, 1626, 1632, 1645, 1656, 1657, 1715, 1716, 1732, 1741, and 1746 through 1786; certificated in any category. Compliance: Required as indicated, unless previously accomplished. To prevent loss of spoilers in the speed brake mode and flap/slat control, accomplish the following: A. Within 30 days after the effective date of this AD, deactivate the in-flight spoiler lockout mechanism, in accordance with McDonnell Douglas Service Bulletin 27-312, dated February 26, 1990. B. Prior to reactivating the in-flight spoiler lockout mechanism, conduct an inspection of the mounting brackets to determine the type and part number (P/N) of the brackets installed. 1. If mounting brackets, P/N 3962598-1A (stainless steel), are installed no further action is required and the in-flight spoiler lockout mechanism may be reactivated, in a manner approved by the Manager, Los Angeles Aircraft Certification Office (ACO), FAA, Transport Airplane Directorate. 2. If mounting brackets, P/N 3962598-1NC (aluminum), are installed, replace them with P/N 3962598-1A brackets prior to reactivating the in-flight spoiler lockout mechanism. NOTE: The aluminum bracket has a primer finish. The stainless steel bracket is plated. 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. D. 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, Los Angeles Aircraft Certification Office (ACO), FAA, Transport Airplane Directorate. NOTE: The request should be submitted directly to the Manager, Los Angeles ACO, and a copy sent to the cognizant FAA Principal Inspector (PI). The PI will then forward comments or concurrence to the Los Angeles ACO. All persons affected by this directive who have not already received the appropriate service information from the manufacturer may obtain copies upon request to McDonnell Douglas Corporation, 3855 Lakewood Boulevard, Long Beach, California 90846, Attention: Business Unit Manager of Publications, C1-HCO (54-60). This information may be examined at the FAA, Northwest Mountain Region, Transport Airplane Directorate, 1601 Lind Avenue S.W., Renton, Washington, or the Los Angeles Aircraft Certification Office, 3229 East Spring Street, Long Beach, California. This amendment (39-6819, AD 90-25-11) becomes effective on December 17, 1990. ## 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 5 of 25 models: MD-88, DC-9-81 (MD-81), DC-9-83 (MD-83), DC-9-87 (MD-87), DC-9-82 (MD-82) ## 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: 100 (100 by airframe model, 0 by engine model) - Makers: Mcdonnell Douglas 99, Douglas 1 Models with the most aircraft: - [Mcdonnell Douglas DC-9-83(MD-83)](https://openairdocs.org/model/mcdonnell-douglas-dc-9-83-md-83): 49 aircraft (airframe model) - [Mcdonnell Douglas DC-9-82(MD-82)](https://openairdocs.org/model/mcdonnell-douglas-dc-9-82-md-82): 22 aircraft (airframe model) - [Mcdonnell Douglas MD-88](https://openairdocs.org/model/mcdonnell-douglas-md-88): 14 aircraft (airframe model) - [Mcdonnell Douglas DC-9-87](https://openairdocs.org/model/mcdonnell-douglas-dc-9-87): 13 aircraft (airframe model) - [Douglas DC-9-83](https://openairdocs.org/model/douglas-dc-9-83): 1 aircraft (airframe model) - [Mcdonnell Douglas DC-9-87 (MD-87)](https://openairdocs.org/model/mcdonnell-douglas-dc-9-87-md-87): 1 aircraft (airframe model) All 7 models: https://openairdocs.org/ad/90-25-11/models.md Every aircraft: https://openairdocs.org/ad/90-25-11/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.