AD 74-05-02
final rule
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Bombardier Inc. | CL-44D4 | CANADAIR Models CL-44-D4 and CL-44-J Airplanes |
| aircraft | Bombardier Inc. | CL-44J | CANADAIR Models CL-44-D4 and CL-44-J Airplanes |
Unsafe Condition
Cracks in the main landing gear uplock actuator cylinder could result in inability to extend the landing gear.
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Required Actions
Modify aircraft per Canadair Service Bulletin No. CL-44-D4-381 with shimming requirements from Service Information Circular No. 317-CL-44-D4. Replace uplock cylinders before 8,000 hours in primary systems, track total service time, and inspect/reidentify cylinders reused in emergency systems.
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Compliance Time
Prior to accumulation of 3,500 hours time in service on the main landing gear uplock actuator cylinders
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Affected Aircraft
Bombardier Inc. CL-44D4 and CL-44J models, all serial numbers
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Federal Register Abstract
Main Landing Gear Uplock Cylinder
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_74-05-02.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 74-05-02 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: CANADAIR Models CL-44-D4 and CL-44-J Airplanes Subject: Main Landing Gear Uplock Cylinder Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 02/26/1974 Make: Bombardier Inc. Model: CL-44D4 | CL-44J Product Type: Aircraft Product Subtype: Large Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 74-05-02 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-1790 AD NUMBER: 74-05-02 SUBJECT HEADING: CANADAIR Models CL-44-D4 and CL-44-J Airplanes ACTION: SUMMARY: DATES: Effective February 26, 1974. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 74-05-02 CANADAIR: Amdt. 39-1790. Applies to CL-44-D4 and CL-44-J airplanes certificated in all categories. Compliance required as indicated. To prevent cracks in the main landing gear uplock actuator cylinder on the Canadair Models CL-44-D4 and CL-44-J aircraft, resulting in the inability to extend the landing gear, accomplish the following: 1. Prior to accumulation of 3,500 hours time in service on the main landing gear uplock actuator cylinders, modify the aircraft in accordance with Canadair Service Bulletin No. CL-44-D4-381, revised September 28, 1968, observing the shimming requirements of Canadair Service Information Circular No. 317-CL-44-D4, dated August 28, 1964, or in accordance with an equivalent procedure approved by the Chief, Engineering and Manufacturing Branch, FAA, Eastern Region. 2. For those aircraft modified as described in paragraph 1, the following apply: a. An uplock actuator cylinder installed in a primary uplock actuator must be replaced prior to the accumulation of 8,000 hours in service in primary uplock actuators. Service time accumulated on uplock cylinders prior to accomplishment of Canadair Service Bulletin No. CL-44-D4-381, must be counted as part of the aforementioned 8,000 hours. b. Cylinders removed from primary uplock actuators including unmodified, single cylinder uplock systems, may be used in emergency uplock actuators provided that: (a) Cylinders are subjected to a dye-penetrant inspection, and are found to be free from cracks. (b) Satisfactory dye-checked cylinders are reidentified to distinguish them from new cylinders. (c) Cylinders do not exceed 16,000 hours total combined service time in primary and emergency systems. c. A new actuator cylinder installed in an emergency uplock system has an unrestricted service life. This AD supersedes AD 65-04-04. This amendment is effective February 26, 1974. FOOTER:
Document Text
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AD Final Rules - DRS_74-05-02.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 74-05-02 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: CANADAIR Models CL-44-D4 and CL-44-J Airplanes Subject: Main Landing Gear Uplock Cylinder Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 02/26/1974 Make: Bombardier Inc. Model: CL-44D4 | CL-44J 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: 74-05-02 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-1790 AD NUMBER: 74-05-02 SUBJECT HEADING: CANADAIR Models CL-44-D4 and CL-44-J Airplanes ACTION: SUMMARY: DATES: Effective February 26, 1974. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 74-05-02 CANADAIR: Amdt. 39-1790. Applies to CL-44-D4 and CL-44-J airplanes certificated in all categories. Compliance required as indicated. To prevent cracks in the main landing gear uplock actuator cylinder on the Canadair Models CL-44-D4 and CL-44-J aircraft, resulting in the inability to extend the landing gear, accomplish the following: 1. Prior to accumulation of 3,500 hours time in service on the main landing gear uplock actuator cylinders, modify the aircraft in accordance with Canadair Service Bulletin No. CL-44-D4-381, revised September 28, 1968, observing the shimming requirements of Canadair Service Information Circular No. 317-CL-44-D4, dated August 28, 1964, or in accordance with an equivalent procedure approved by the Chief, Engineering and Manufacturing Branch, FAA, Eastern Region. 2. For those aircraft modified as described in paragraph 1, the following apply: a. An uplock actuator cylinder installed in a primary uplock actuator must be replaced prior to the accumulation of 8,000 hours in service in primary uplock actuators. Service time accumulated on uplock cylinders prior to accomplishment of Canadair Service Bulletin No. CL-44-D4-381, must be counted as part of the aforementioned 8,000 hours. b. Cylinders removed from primary uplock actuators including unmodified, single cylinder uplock systems, may be used in emergency uplock actuators provided that: (a) Cylinders are subjected to a dye-penetrant inspection, and are found to be free from cracks. (b) Satisfactory dye-checked cylinders are reidentified to distinguish them from new cylinders. (c) Cylinders do not exceed 16,000 hours total combined service time in primary and emergency systems. c. A new actuator cylinder installed in an emergency uplock system has an unrestricted service life. This AD supersedes AD 65-04-04. This amendment is effective February 26, 1974. FOOTER:
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