AD 71-01-02
final rule
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Vickers-Armstrongs (Aircraft Limited) | Viscount 744 | Airworthiness Directives; BRITISH AIRCRAFT CORPORATION Models 744, 745D, and 810 Series Airplanes |
| aircraft | Vickers-Armstrongs (Aircraft Limited) | Viscount 745D | Airworthiness Directives; BRITISH AIRCRAFT CORPORATION Models 744, 745D, and 810 Series Airplanes |
| aircraft | Vickers-Armstrongs (Aircraft Limited) | Viscount 810 | Airworthiness Directives; BRITISH AIRCRAFT CORPORATION Models 744, 745D, and 810 Series Airplanes |
Unsafe Condition
Failure of the flap gearbox drive motor assembly due to break-up of the steel inner clutch plate.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Replace the flap gearbox drive motor clutch assembly with a solid spline adaptor using Rotax Modification No. 4603c Part A or equivalent. Replace obsolete clutch driving shafts, clutch shafts, and brake drum assemblies with specified replacement parts. Inspect brake drum assemblies for cracks every 5,000 landings and replace cracked components. Remove AD 68-23-07 placards and temporary procedures after completing replacements.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Within the next 25 landings after January 21, 1971, or within the next 700 landings after the clutch plate was replaced under AD 68-23-07, whichever is later. Inspections must occur within 500 landings after January 21, 1971, and every 5,000 landings thereafter.
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
Vickers-Armstrongs (Aircraft Limited) Viscount Models 744, 745D, and 810 series airplanes.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Flap Drive Motor Assembly
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_71-01-02.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 71-01-02 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; BRITISH AIRCRAFT CORPORATION Models 744, 745D, and 810 Series Airplanes Subject: Flap Drive Motor Assembly Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 01/21/1971 Make: Vickers-Armstrongs (Aircraft Limited) Model: Viscount 744 | Viscount 745D | Viscount 810 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: 71-01-02 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-1133 AD NUMBER: 71-01-02 SUBJECT HEADING: Airworthiness Directives; BRITISH AIRCRAFT CORPORATION Models 744, 745D, and 810 Series Airplanes ACTION: SUMMARY: DATES: Effective January 21, 1971. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 71-01-02 BRITISH AIRCRAFT CORPORATION: Amdt. 39-1133. Applies to Viscount Models 744, 745D, and 810 series airplanes. Compliance is required as indicated. To prevent failure of the flap gearbox drive motor assembly due to break-up of the steel inner clutch plate, accomplish the following: (a) Within the next 25 landings after the effective date of this AD, or within the next 700 landings after the clutch plate was replaced in accordance with AD 68-23-07, whichever occurs later, unless already accomplished, accomplish the following: (1) Replace the flap gearbox drive motor clutch assembly with a solid spline adaptor by incorporating Rotax Modification No. 4603c Part A in accordance with Rotax Service Bulletin 24-337, Revision 2, dated November 24, 1969, or later ARB-approved issue or an FAA- approved equivalent. (2) Replace obsolete clutch driving shafts, clutch shafts, and brake drum assemblies of the flap gearbox drive motor assembly having obsolete part numbers, with serviceable replacement components having replacement part numbers, in accordance with the following table: Component Obsolete Part Numbers Replacement Part Numbers Clutch driving shaft N117500 and N145421 N149327, N187295, or N196101 Clutch shaft Brake drum assembly N98825 N117504 and N117504/1 N149328 N149329 (3) Replace clutch driving shafts P/Ns N149327 or N187295, having a total of 5,000 or more landings on the shaft with a serviceable shaft, P/N 149327, N187295, or N196101. (b) Replace clutch driving shafts P/Ns N149327 and N187295 at intervals not to exceed 5,000 landings on the shaft, and replace clutch driving shafts P/N N196101 at intervals not to exceed 10,000 landings on the shaft. (c) Within the next 500 landings after the effective date of this AD, unless already accomplished within the last 4,500 landings, and thereafter at intervals not to exceed 5,000 landings since the last inspection, visually inspect the brake drum assembly P/N 149329 for cracks in accordance with Rotax Service Bulletin No. 24-142 dated February 11, 1966, or later ARB-approved issue or an FAA-approved equivalent, and replace drums found to be cracked with serviceable drums of the same part number. (d) Upon completion of the replacements required by paragraph (a), remove the placard and the temporary in flight procedures in the Airplane Flight Manual required by AD 68- 23-07. (e) For the purpose of complying with this AD, subject to acceptance by the assigned maintenance inspector the number of landings may be determined by dividing each airplane's hours' time in service by the operator's fleet average time from take-off to landing for the BAC Viscount airplane. (British Aircraft Corporation Preliminary Technical Leaflets No. 148 and No. 283 cover this same subject.) This supersedes Amendment 39-263 (31 F.R. 10022), AD 66-19-05, and Amendment 39- 695 (33 F.R. 16493), AD 68-23-07. This amendment becomes effective January 21, 1971. FOOTER:
Document Text
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AD Final Rules - DRS_71-01-02.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 71-01-02 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; BRITISH AIRCRAFT CORPORATION Models 744, 745D, and 810 Series Airplanes Subject: Flap Drive Motor Assembly Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 01/21/1971 Make: Vickers-Armstrongs (Aircraft Limited) Model: Viscount 744 | Viscount 745D | Viscount 810 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: 71-01-02 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-1133 AD NUMBER: 71-01-02 SUBJECT HEADING: Airworthiness Directives; BRITISH AIRCRAFT CORPORATION Models 744, 745D, and 810 Series Airplanes ACTION: SUMMARY: DATES: Effective January 21, 1971. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 71-01-02 BRITISH AIRCRAFT CORPORATION: Amdt. 39-1133. Applies to Viscount Models 744, 745D, and 810 series airplanes. Compliance is required as indicated. To prevent failure of the flap gearbox drive motor assembly due to break-up of the steel inner clutch plate, accomplish the following: (a) Within the next 25 landings after the effective date of this AD, or within the next 700 landings after the clutch plate was replaced in accordance with AD 68-23-07, whichever occurs later, unless already accomplished, accomplish the following: (1) Replace the flap gearbox drive motor clutch assembly with a solid spline adaptor by incorporating Rotax Modification No. 4603c Part A in accordance with Rotax Service Bulletin 24-337, Revision 2, dated November 24, 1969, or later ARB-approved issue or an FAA- approved equivalent. (2) Replace obsolete clutch driving shafts, clutch shafts, and brake drum assemblies of the flap gearbox drive motor assembly having obsolete part numbers, with serviceable replacement components having replacement part numbers, in accordance with the following table: Component Obsolete Part Numbers Replacement Part Numbers Clutch driving shaft N117500 and N145421 N149327, N187295, or N196101 Clutch shaft Brake drum assembly N98825 N117504 and N117504/1 N149328 N149329 (3) Replace clutch driving shafts P/Ns N149327 or N187295, having a total of 5,000 or more landings on the shaft with a serviceable shaft, P/N 149327, N187295, or N196101. (b) Replace clutch driving shafts P/Ns N149327 and N187295 at intervals not to exceed 5,000 landings on the shaft, and replace clutch driving shafts P/N N196101 at intervals not to exceed 10,000 landings on the shaft. (c) Within the next 500 landings after the effective date of this AD, unless already accomplished within the last 4,500 landings, and thereafter at intervals not to exceed 5,000 landings since the last inspection, visually inspect the brake drum assembly P/N 149329 for cracks in accordance with Rotax Service Bulletin No. 24-142 dated February 11, 1966, or later ARB-approved issue or an FAA-approved equivalent, and replace drums found to be cracked with serviceable drums of the same part number. (d) Upon completion of the replacements required by paragraph (a), remove the placard and the temporary in flight procedures in the Airplane Flight Manual required by AD 68- 23-07. (e) For the purpose of complying with this AD, subject to acceptance by the assigned maintenance inspector the number of landings may be determined by dividing each airplane's hours' time in service by the operator's fleet average time from take-off to landing for the BAC Viscount airplane. (British Aircraft Corporation Preliminary Technical Leaflets No. 148 and No. 283 cover this same subject.) This supersedes Amendment 39-263 (31 F.R. 10022), AD 66-19-05, and Amendment 39- 695 (33 F.R. 16493), AD 68-23-07. This amendment becomes effective January 21, 1971. FOOTER:
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