AD 90-05-03
final rule
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Bombardier Inc. | DHC-8-301 | Airworthiness Directives; De Havilland Model DHC-8-300 Series Airplanes |
| aircraft | Bombardier Inc. | DHC-8-311 | Airworthiness Directives; De Havilland Model DHC-8-300 Series Airplanes |
| aircraft | Bombardier Inc. | DHC-8-315 | Airworthiness Directives; De Havilland Model DHC-8-300 Series Airplanes |
Unsafe Condition
Cracks or complete separation of the bleed air precooler mounting lugs could cause rupture of the engine bleed air ducts.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Within 50 hours time-in-service after the effective date, and every 50 hours time-in-service thereafter, perform a visual inspection for cracks or separation of the mounting lugs per de Havilland Alert Service Bulletin A8-21-32. If more than one lug has cracks or any lug is separated, repair before further flight per the same service bulletin.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Within the next 50 hours time-in-service after the effective date of this AD, and thereafter at intervals not to exceed 50 hours time-in-service
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
De Havilland Model DHC-8-301, DHC-8-311, DHC-8-315 airplanes, serial numbers 100 through 231 inclusive
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Precooler Mounting Lugs
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_90-05-03.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 90-05-03 Document Type: AD Final Rules Docket Number: 89-NM-236-AD Subject Heading: Airworthiness Directives; De Havilland Model DHC-8-300 Series Airplanes Subject: Precooler Mounting Lugs Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 04/06/1990 Make: Bombardier Inc. Model: DHC-8-301 | DHC-8-311 | DHC-8-315 Product Type: Aircraft Product Subtype: Large Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 90-05-03 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: 89-NM-236-AD AMENDMENT: 39-6520 AD NUMBER: 90-05-03 SUBJECT HEADING: Airworthiness Directives; De Havilland Model DHC-8-300 Series Airplanes ACTION: SUMMARY: DATES: Effective April 6, 1990 ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 90-05-03 BOEING OF CANADA, LTD., DE HAVILLAND DIVISION: Amendment 39- 6520. Docket No. 89-NM-236-AD. Applicability: de Havilland Model DHC-8-300 series airplanes, Serial Numbers 100 through 231, inclusive, certificated in any category. Compliance: Required as indicated, unless previously accomplished. To prevent possible rupture of the engine bleed air ducts, accomplish the following: A. Within the next 50 hours time-in-service after the effective date of this AD, and thereafter at intervals not to exceed 50 hours time-in-service, perform a visual inspection to detect cracks or complete separation of the bleed air precooler mounting lugs, in accordance with de Havilland Alert Service Bulletin A8-21-32, Revision A, dated November 22, 1989. B. If cracks are found in more than one lug, or if any lug has completely separated, repair prior to further flight, in accordance with de Havilland Alert Service Bulletin A8-21-32, Revision A, dated November 22, 1989. C. 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, Northwest Mountain Region. NOTE: The request should be forwarded through an FAA Principal Maintenance Inspector (PMI), who will either concur or comment and then send it to the Manager, Standardization Branch, ANM-113. 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. All persons affected by this directive who have not already received the appropriate service information from the manufacturer may obtain copies upon request to Boeing of Canada, Ltd., de Havilland Division, Garratt Boulevard, Downsview, Ontario M3K 1Y5, Canada. This information may be examined at the FAA, Northwest Mountain Region, Transport Airplane Directorate, 17900 Pacific Highway South, Seattle, Washington, or at the FAA, New England Region, New York Aircraft Certification Office, 181 South Franklin Avenue, Room 202, Valley Stream, New York 11581. This amendment (39-6520, AD 90-05-03) becomes effective on April 6, 1990. FOOTER:
Document Text
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AD Final Rules - DRS_90-05-03.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 90-05-03 Document Type: AD Final Rules Docket Number: 89-NM-236-AD Subject Heading: Airworthiness Directives; De Havilland Model DHC-8-300 Series Airplanes Subject: Precooler Mounting Lugs Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 04/06/1990 Make: Bombardier Inc. Model: DHC-8-301 | DHC-8-311 | DHC-8-315 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: 90-05-03 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: 89-NM-236-AD AMENDMENT: 39-6520 AD NUMBER: 90-05-03 SUBJECT HEADING: Airworthiness Directives; De Havilland Model DHC-8-300 Series Airplanes ACTION: SUMMARY: DATES: Effective April 6, 1990 ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 90-05-03 BOEING OF CANADA, LTD., DE HAVILLAND DIVISION: Amendment 39- 6520. Docket No. 89-NM-236-AD. Applicability: de Havilland Model DHC-8-300 series airplanes, Serial Numbers 100 through 231, inclusive, certificated in any category. Compliance: Required as indicated, unless previously accomplished. To prevent possible rupture of the engine bleed air ducts, accomplish the following: A. Within the next 50 hours time-in-service after the effective date of this AD, and thereafter at intervals not to exceed 50 hours time-in-service, perform a visual inspection to detect cracks or complete separation of the bleed air precooler mounting lugs, in accordance with de Havilland Alert Service Bulletin A8-21-32, Revision A, dated November 22, 1989. B. If cracks are found in more than one lug, or if any lug has completely separated, repair prior to further flight, in accordance with de Havilland Alert Service Bulletin A8-21-32, Revision A, dated November 22, 1989. C. 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, Northwest Mountain Region. NOTE: The request should be forwarded through an FAA Principal Maintenance Inspector (PMI), who will either concur or comment and then send it to the Manager, Standardization Branch, ANM-113. 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. All persons affected by this directive who have not already received the appropriate service information from the manufacturer may obtain copies upon request to Boeing of Canada, Ltd., de Havilland Division, Garratt Boulevard, Downsview, Ontario M3K 1Y5, Canada. This information may be examined at the FAA, Northwest Mountain Region, Transport Airplane Directorate, 17900 Pacific Highway South, Seattle, Washington, or at the FAA, New England Region, New York Aircraft Certification Office, 181 South Franklin Avenue, Room 202, Valley Stream, New York 11581. This amendment (39-6520, AD 90-05-03) becomes effective on April 6, 1990. FOOTER:
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