AD 91-04-05
final rule
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | BAE Systems (Operations) Limited | ATP | Airworthiness Directives; British Aerospace Model ATP Series Airplanes |
Unsafe Condition
Loss of all DC electrical power due to stall warning contoured airframe heaters being connected to the essential 28V DC busbars.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Disconnect stall warning contoured airframe heaters from essential 28V DC busbars and reconnect them to nonessential busbars within 60 days after the effective date. Use British Aerospace Service Bulletin ATP-27-18, Revision 1, dated January 31, 1990. Alternate compliance may be approved by the FAA Manager, Standardization Branch.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
within 60 days after the effective date of this AD
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
British Aerospace Model ATP series airplanes, Serial Numbers 2002 through 2018, inclusive, certificated in any category.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Stall Warning Airframe Heaters
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_91-04-05.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 91-04-05 Document Type: AD Final Rules Docket Number: 90-NM-235-AD Subject Heading: Airworthiness Directives; British Aerospace Model ATP Series Airplanes Subject: Stall Warning Airframe Heaters Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 03/18/1991 Make: BAE Systems (Operations) Limited Model: ATP Product Type: Aircraft Product Subtype: Large Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 91-04-05 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: 90-NM-235-AD AMENDMENT: 39-6889 AD NUMBER: 91-04-05 SUBJECT HEADING: Airworthiness Directives; British Aerospace Model ATP Series Airplanes ACTION: SUMMARY: DATES: Effective on March 18, 1991. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 91-04-05 BRITISH AEROSPACE: Amendment 39-6889. Docket No. 90-NM-235-AD. Applicability: Model ATP series airplanes, Serial Numbers 2002 through 2018, inclusive, certificated in any category. Compliance: Required as indicated, unless previously accomplished. To prevent the loss of all DC electrical power, accomplish the following: A. Within 60 days after the effective date of this AD, disconnect the stall warning contoured airframe heaters from the essential 28V DC busbars and reconnect them to the nonessential busbars, in accordance with the Accomplishment Instructions in British Aerospace Service Bulletin ATP-27-18, Revision 1, dated January 31, 1990. 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, Standardization Branch, ANM-113, FAA, Transport Airplane Directorate. NOTE: The request should be submitted directly to the Manager, Standardization Branch, ANM-113, and a copy sent to the cognizant FAA Principal Inspector (PI). The PI will then forward comments or concurrence to the Manager, Standardization Branch, ANM-113. 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. All persons affected by this directive who have not already received the appropriate service documents from the manufacturer may obtain copies upon request to British Aerospace, PLC, Librarian for Service Bulletins, Dulles International Airport, Washington, D.C. 20041-0414. These documents may be examined at the FAA, Northwest Mountain Region, Transport Airplane Directorate, 1601 Lind Avenue, S.W., Renton, Washington 98055-4056. This amendment (39-6889, AD 91-04-05) becomes effective on March 18, 1991. FOOTER:
Document Text
Show stored source text (verify against official source)
AD Final Rules - DRS_91-04-05.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 91-04-05 Document Type: AD Final Rules Docket Number: 90-NM-235-AD Subject Heading: Airworthiness Directives; British Aerospace Model ATP Series Airplanes Subject: Stall Warning Airframe Heaters Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 03/18/1991 Make: BAE Systems (Operations) Limited Model: ATP Product Type: Aircraft Product Subtype: Large Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 91-04-05 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: 90-NM-235-AD AMENDMENT: 39-6889 AD NUMBER: 91-04-05 SUBJECT HEADING: Airworthiness Directives; British Aerospace Model ATP Series Airplanes ACTION: SUMMARY: DATES: Effective on March 18, 1991. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 91-04-05 BRITISH AEROSPACE: Amendment 39-6889. Docket No. 90-NM-235-AD. Applicability: Model ATP series airplanes, Serial Numbers 2002 through 2018, inclusive, certificated in any category. Compliance: Required as indicated, unless previously accomplished. To prevent the loss of all DC electrical power, accomplish the following: A. Within 60 days after the effective date of this AD, disconnect the stall warning contoured airframe heaters from the essential 28V DC busbars and reconnect them to the nonessential busbars, in accordance with the Accomplishment Instructions in British Aerospace Service Bulletin ATP-27-18, Revision 1, dated January 31, 1990. 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, Standardization Branch, ANM-113, FAA, Transport Airplane Directorate. NOTE: The request should be submitted directly to the Manager, Standardization Branch, ANM-113, and a copy sent to the cognizant FAA Principal Inspector (PI). The PI will then forward comments or concurrence to the Manager, Standardization Branch, ANM-113. 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. All persons affected by this directive who have not already received the appropriate service documents from the manufacturer may obtain copies upon request to British Aerospace, PLC, Librarian for Service Bulletins, Dulles International Airport, Washington, D.C. 20041-0414. These documents may be examined at the FAA, Northwest Mountain Region, Transport Airplane Directorate, 1601 Lind Avenue, S.W., Renton, Washington 98055-4056. This amendment (39-6889, AD 91-04-05) becomes effective on March 18, 1991. FOOTER:
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Retrieved: Apr 8, 2026
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