AD 91-16-07
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | BAE Systems (Operations) Limited | ATP | Airworthiness Directives; British Aerospace Model ATP Series Airplanes |
Unsafe Condition
The Smiths Industries Altimeter Repeater Units, Part Number 1205AM1, may fail to provide accurate altitude data due to a non-hardened knobshaft (Part Number AM10454) and improperly mounted microswitch.
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Required Actions
Install a hardened knobshaft (Part Number AM10588) replacing Part Number AM10454, remount the microswitch per Smiths Industries Modification No. 02, and comply with British Aerospace Service Bulletin ATP-34-40. Alternative methods may be approved by the FAA.
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Compliance Time
within 120 days after the effective date of this AD
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Affected Aircraft
British Aerospace Model ATP series airplanes equipped with Smiths Industries Altimeter Repeater Units, Part Number 1205AM1
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Federal Register Abstract
Altimeter Repeater Units
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_91-16-07.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 91-16-07 Document Type: AD Final Rules Docket Number: 91-NM-79-AD Subject Heading: Airworthiness Directives; British Aerospace Model ATP Series Airplanes Subject: Altimeter Repeater Units Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 09/11/1991 Make: BAE Systems (Operations) Limited Model: ATP Product Type: Aircraft Product Subtype: Large Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 91-16-07 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: 91-NM-79-AD AMENDMENT: 39-7097 AD NUMBER: 91-16-07 SUBJECT HEADING: Airworthiness Directives; British Aerospace Model ATP Series Airplanes ACTION: SUMMARY: DATES: Effective on September 11, 1991. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 91-16-07 BRITISH AEROSPACE: Amendment 39-7097. Docket No. 91-NM-79-AD. Applicability: Model ATP series airplanes, equipped with Smiths Industries Altimeter Repeater Units, Part Number 1205AM1, certificated in any category. Compliance: Required within 120 days after the effective date of this AD, unless previously accomplished. To ensure the pilot receives accurate altitude data, accomplish the following: A. Install a hardened knobshaft, Part Number AM10588, in place of Part Number AM10454, and remount the microswitch (Smiths Industries Modification No. 02), in accordance with British Aerospace Service Bulletin ATP-34-40, dated October 20, 1990. NOTE: The British Aerospace service bulletin references Smiths Industries Service Bulletin 1205AM-34-756 for additional instructions. B. 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, Standardization Branch, ANM-113, 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, 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. D. The modification requirement shall be done in accordance with British Aerospace Service Bulletin ATP-34-40, dated October 20, 1990. This incorporation by reference was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR Part 51. Copies may be obtained from British Aerospace, PLC, Librarian for Service Bulletins, P.O. Box 17414, Dulles International Airport, Washington, D.C. 20041. Copies may be inspected at the FAA, Transport Airplane Directorate, Renton, Washington; or at the Office of the Federal Register, 1100 L Street N.W., Room 8401, Washington, D.C. This amendment (39-7097, AD 91-16-07) becomes effective on September 11, 1991. FOOTER:
Document Text
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AD Final Rules - DRS_91-16-07.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 91-16-07 Document Type: AD Final Rules Docket Number: 91-NM-79-AD Subject Heading: Airworthiness Directives; British Aerospace Model ATP Series Airplanes Subject: Altimeter Repeater Units Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 09/11/1991 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: 91-16-07 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: 91-NM-79-AD AMENDMENT: 39-7097 AD NUMBER: 91-16-07 SUBJECT HEADING: Airworthiness Directives; British Aerospace Model ATP Series Airplanes ACTION: SUMMARY: DATES: Effective on September 11, 1991. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 91-16-07 BRITISH AEROSPACE: Amendment 39-7097. Docket No. 91-NM-79-AD. Applicability: Model ATP series airplanes, equipped with Smiths Industries Altimeter Repeater Units, Part Number 1205AM1, certificated in any category. Compliance: Required within 120 days after the effective date of this AD, unless previously accomplished. To ensure the pilot receives accurate altitude data, accomplish the following: A. Install a hardened knobshaft, Part Number AM10588, in place of Part Number AM10454, and remount the microswitch (Smiths Industries Modification No. 02), in accordance with British Aerospace Service Bulletin ATP-34-40, dated October 20, 1990. NOTE: The British Aerospace service bulletin references Smiths Industries Service Bulletin 1205AM-34-756 for additional instructions. B. 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, Standardization Branch, ANM-113, 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, 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. D. The modification requirement shall be done in accordance with British Aerospace Service Bulletin ATP-34-40, dated October 20, 1990. This incorporation by reference was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR Part 51. Copies may be obtained from British Aerospace, PLC, Librarian for Service Bulletins, P.O. Box 17414, Dulles International Airport, Washington, D.C. 20041. Copies may be inspected at the FAA, Transport Airplane Directorate, Renton, Washington; or at the Office of the Federal Register, 1100 L Street N.W., Room 8401, Washington, D.C. This amendment (39-7097, AD 91-16-07) becomes effective on September 11, 1991. FOOTER:
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