AD 66-27-04
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Bombardier Inc. | CL-44D4 | Airworthiness Directives; CANADAIR Model CL-44D4 Airplanes |
Unsafe Condition
Cracks in the main landing gear keel vertical posts and horizontal lower reinforcing angle members in the inboard nacelles could result in structural failure.
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Required Actions
Visually inspect the vertical post members and nesting angles for cracks within 50 hours' time in service after the effective date, and thereafter every 500 hours' time in service. Repairs or replacements must be done in an FAA-approved manner before further flight if cracks are found. Discontinue inspections after approved modifications as specified.
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Compliance Time
within the next 50 hours' time in service after the effective date of this AD, unless already accomplished within the last 450 hours' time in service, and thereafter at intervals not to exceed 500 hours' time in service from the last inspection
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Affected Aircraft
Bombardier Inc. Model CL-44D4 airplanes
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Federal Register Abstract
Main Landing Gear Keel Members
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_66-27-04.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 66-27-04 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; CANADAIR Model CL-44D4 Airplanes Subject: Main Landing Gear Keel Members Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 11/12/1966 Make: Bombardier Inc. Model: CL-44D4 Product Type: Aircraft Product Subtype: Large Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 66-27-04 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-299 AD NUMBER: 66-27-04 SUBJECT HEADING: Airworthiness Directives; CANADAIR Model CL-44D4 Airplanes ACTION: SUMMARY: DATES: Effective November 12, 1966. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 66-27-04 CANADAIR: Amdt. 39-299 Part 39 Federal Register November 2, 1966. Applies to Model CL-44D4 airplanes. Compliance required as indicated. To detect cracks in the main landing gear keel vertical posts and horizontal lower reinforcing angle members in the inboard nacelles, accomplish the following: (a) For airplanes incorporating the modification specified in Canadair Service Information Circular No. 247-CL44D4, dated April 9, 1963, within the next 50 hours' time in service after the effective date of this AD, unless already accomplished within the last 450 hours' time in service, and thereafter at intervals not to exceed 500 hours' time in service from the last inspection, visually inspect the vertical post members and nesting angles for cracks. (b) For airplanes other than those specified in (a), within the next 50 hours' time in service after the effective date of this AD, unless already accomplished within the last 450 hours' time in service, and thereafter at intervals not to exceed 500 hours' time in service from the last inspection, visually inspect the vertical post members and lower reinforcing angles for cracks, in accordance with paragraphs (a), (b), (c) and (d) of "Inspection Procedure" of Canadair Service Information Circular, Issue No. 2, No. 247-CL44D4, dated May 17, 1966, or later FAA-approved revision or an FAA-approved equivalent. (c) If a crack is found during an inspection required by (a) or (b), repair the crack in an FAA-approved manner, or replace the part with a part of the same part number that has been inspected in accordance with this AD and found free of cracks or with an equivalent part approved by the Chief, Engineering and Manufacturing Branch, FAA Eastern Region, before further flight, except that the airplane may be flown in accordance with FAR 21.197 to a base where the repair can be performed. (d) The repetitive inspection of the vertical post members required by (a) and (b) may be discontinued when the vertical post members are modified with a modification approved by the Chief, Engineering and Manufacturing Branch, FAA Eastern Region. (e) The repetitive inspection of the nesting angles required by (a) may be discontinued when the modification specified in Canadair Service Information Circular No. 247- CL44D4, dated April 9, 1963, is disassembled, the lower reinforcing angles and nesting angles are visually inspected for cracks and repaired or replaced as necessary in accordance with (c), and reinstalled in accordance with Canadair Service Bulletin CL44-452, dated July 8, 1966, or later FAA-approved revision, or an equivalent approved by the Chief, Engineering and Manufacturing Branch, FAA Eastern Region. (f) The repetitive inspection of the lower reinforcing angle members required by (b) may be discontinued when the lower reinforcing angles are modified in accordance with Canadair Service Bulletin CL44-452, dated July 8, 1966, or later FAA-approved revision, or an equivalent approved by the Chief, Engineering and Manufacturing Branch, FAA Eastern Region. (g) Upon request of the operator, an FAA maintenance inspector, subject to prior approval of the Chief, Engineering and Manufacturing Branch, FAA Eastern Region, may adjust the repetitive inspection intervals specified in this AD to permit compliance at an established inspection period of the operator if the request contains substantiating data to justify the increase for that operator. This directive effective November 12, 1966. FOOTER:
Document Text
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AD Final Rules - DRS_66-27-04.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 66-27-04 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; CANADAIR Model CL-44D4 Airplanes Subject: Main Landing Gear Keel Members Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 11/12/1966 Make: Bombardier Inc. Model: CL-44D4 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: 66-27-04 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-299 AD NUMBER: 66-27-04 SUBJECT HEADING: Airworthiness Directives; CANADAIR Model CL-44D4 Airplanes ACTION: SUMMARY: DATES: Effective November 12, 1966. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 66-27-04 CANADAIR: Amdt. 39-299 Part 39 Federal Register November 2, 1966. Applies to Model CL-44D4 airplanes. Compliance required as indicated. To detect cracks in the main landing gear keel vertical posts and horizontal lower reinforcing angle members in the inboard nacelles, accomplish the following: (a) For airplanes incorporating the modification specified in Canadair Service Information Circular No. 247-CL44D4, dated April 9, 1963, within the next 50 hours' time in service after the effective date of this AD, unless already accomplished within the last 450 hours' time in service, and thereafter at intervals not to exceed 500 hours' time in service from the last inspection, visually inspect the vertical post members and nesting angles for cracks. (b) For airplanes other than those specified in (a), within the next 50 hours' time in service after the effective date of this AD, unless already accomplished within the last 450 hours' time in service, and thereafter at intervals not to exceed 500 hours' time in service from the last inspection, visually inspect the vertical post members and lower reinforcing angles for cracks, in accordance with paragraphs (a), (b), (c) and (d) of "Inspection Procedure" of Canadair Service Information Circular, Issue No. 2, No. 247-CL44D4, dated May 17, 1966, or later FAA-approved revision or an FAA-approved equivalent. (c) If a crack is found during an inspection required by (a) or (b), repair the crack in an FAA-approved manner, or replace the part with a part of the same part number that has been inspected in accordance with this AD and found free of cracks or with an equivalent part approved by the Chief, Engineering and Manufacturing Branch, FAA Eastern Region, before further flight, except that the airplane may be flown in accordance with FAR 21.197 to a base where the repair can be performed. (d) The repetitive inspection of the vertical post members required by (a) and (b) may be discontinued when the vertical post members are modified with a modification approved by the Chief, Engineering and Manufacturing Branch, FAA Eastern Region. (e) The repetitive inspection of the nesting angles required by (a) may be discontinued when the modification specified in Canadair Service Information Circular No. 247- CL44D4, dated April 9, 1963, is disassembled, the lower reinforcing angles and nesting angles are visually inspected for cracks and repaired or replaced as necessary in accordance with (c), and reinstalled in accordance with Canadair Service Bulletin CL44-452, dated July 8, 1966, or later FAA-approved revision, or an equivalent approved by the Chief, Engineering and Manufacturing Branch, FAA Eastern Region. (f) The repetitive inspection of the lower reinforcing angle members required by (b) may be discontinued when the lower reinforcing angles are modified in accordance with Canadair Service Bulletin CL44-452, dated July 8, 1966, or later FAA-approved revision, or an equivalent approved by the Chief, Engineering and Manufacturing Branch, FAA Eastern Region. (g) Upon request of the operator, an FAA maintenance inspector, subject to prior approval of the Chief, Engineering and Manufacturing Branch, FAA Eastern Region, may adjust the repetitive inspection intervals specified in this AD to permit compliance at an established inspection period of the operator if the request contains substantiating data to justify the increase for that operator. This directive effective November 12, 1966. FOOTER:
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Retrieved: Apr 8, 2026
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