AD 77-11-02
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Airbus Helicopters Deutschland GmbH | BO-105A | Airworthiness Directives; Messerschmitt-Bolkow-Blohm GmbH Model BO-105 Helicopters |
| aircraft | Airbus Helicopters Deutschland GmbH | BO-105C | Airworthiness Directives; Messerschmitt-Bolkow-Blohm GmbH Model BO-105 Helicopters |
| aircraft | Airbus Helicopters Deutschland GmbH | BO-105S | Airworthiness Directives; Messerschmitt-Bolkow-Blohm GmbH Model BO-105 Helicopters |
Unsafe Condition
Failure of the main rotor hub quadruple nuts and associated bolts could result in loss of the main rotor.
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Required Actions
Inspect main rotor hub quadruple nuts (P/N 105-14101.19, 105-14101.20) and bolts (P/N 105-14101.22, 105-14101.23) with over 1,400 hours time in service using magnaflux or FAA-approved equivalent. Replace cracked parts before flight. Replace nuts/bolts before 2,400 hours total time in service.
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Compliance Time
Within the next 100 hours time in service after the effective date (June 14, 1977), unless already accomplished within the last 200 hours time in service. Thereafter at intervals not to exceed 300 hours time in service from the last inspection.
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Affected Aircraft
Messerschmitt-Bolkow-Blohm GmbH Model BO-105A, BO-105C, BO-105S helicopters certificated in all categories.
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Federal Register Abstract
Main Rotor
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_77-11-02.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 77-11-02 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Messerschmitt-Bolkow-Blohm GmbH Model BO-105 Helicopters Subject: Main Rotor Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 06/14/1977 Make: Airbus Helicopters Deutschland GmbH Model: BO-105A | BO-105C | BO-105S Product Type: Aircraft Product Subtype: Rotorcraft Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 77-11-02 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-2912 AD NUMBER: 77-11-02 SUBJECT HEADING: Airworthiness Directives; Messerschmitt-Bolkow-Blohm GmbH Model BO-105 Helicopters ACTION: SUMMARY: DATES: Effective June 14, 1977. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 77-11-02 MESSERSCHMITT-BOLKOW-BLOHM GmbH: Amendment 39-2912. Applies to Model BO-105 helicopters, certificated in all categories. Compliance is required as indicated. To prevent the possible failure of the main rotor hub quadruple nuts and the consequent loss of the main rotor, accomplish the following: (a) For main rotor hub quadruple nuts, P/N's 105-14101.19 and 105-14101.20 and associated bolts, P/N's 105-14101.22 and 105-14101.23, with more than 1,400 hours total time in service, within the next 100 hours time in service after the effective date of this AD, unless already accomplished within the last 200 hours time in service, and thereafter at intervals not to exceed 300 hours time in service from the last inspection, remove the quadruple nuts and associated bolts and inspect them for cracks using a magnaflux process, or an FAA-approved equivalent. (b) If a crack is found in a nut or bolt during any of the inspections required by this AD, before further flight, replace the cracked part with a serviceable part of the same part number. For parts installed as replacements, before the accumulation of 1,500 hours total time in service on the replacement parts and thereafter at intervals not to exceed 300 hours time in service from the last inspection, remove the replacement quadruple nuts and associated bolts and inspect them for cracks using a magnaflux process or an FAA-approved equivalent. (c) Before the accumulation of 2,400 hours total time in service on a quadruple nut or bolt specified in paragraph (a) of this AD, replace the quadruple nuts and associated bolts with serviceable nuts and bolts of the same part numbers and comply with paragraphs (a) and (b) of this AD for the replacement parts. (MBB Service Bulletin No. 10-18 dated July 18, 1975, covers this same subject.) This amendment becomes effective June 14, 1977. FOOTER:
Document Text
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AD Final Rules - DRS_77-11-02.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 77-11-02 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Messerschmitt-Bolkow-Blohm GmbH Model BO-105 Helicopters Subject: Main Rotor Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 06/14/1977 Make: Airbus Helicopters Deutschland GmbH Model: BO-105A | BO-105C | BO-105S Product Type: Aircraft Product Subtype: Rotorcraft Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 77-11-02 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-2912 AD NUMBER: 77-11-02 SUBJECT HEADING: Airworthiness Directives; Messerschmitt-Bolkow-Blohm GmbH Model BO-105 Helicopters ACTION: SUMMARY: DATES: Effective June 14, 1977. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 77-11-02 MESSERSCHMITT-BOLKOW-BLOHM GmbH: Amendment 39-2912. Applies to Model BO-105 helicopters, certificated in all categories. Compliance is required as indicated. To prevent the possible failure of the main rotor hub quadruple nuts and the consequent loss of the main rotor, accomplish the following: (a) For main rotor hub quadruple nuts, P/N's 105-14101.19 and 105-14101.20 and associated bolts, P/N's 105-14101.22 and 105-14101.23, with more than 1,400 hours total time in service, within the next 100 hours time in service after the effective date of this AD, unless already accomplished within the last 200 hours time in service, and thereafter at intervals not to exceed 300 hours time in service from the last inspection, remove the quadruple nuts and associated bolts and inspect them for cracks using a magnaflux process, or an FAA-approved equivalent. (b) If a crack is found in a nut or bolt during any of the inspections required by this AD, before further flight, replace the cracked part with a serviceable part of the same part number. For parts installed as replacements, before the accumulation of 1,500 hours total time in service on the replacement parts and thereafter at intervals not to exceed 300 hours time in service from the last inspection, remove the replacement quadruple nuts and associated bolts and inspect them for cracks using a magnaflux process or an FAA-approved equivalent. (c) Before the accumulation of 2,400 hours total time in service on a quadruple nut or bolt specified in paragraph (a) of this AD, replace the quadruple nuts and associated bolts with serviceable nuts and bolts of the same part numbers and comply with paragraphs (a) and (b) of this AD for the replacement parts. (MBB Service Bulletin No. 10-18 dated July 18, 1975, covers this same subject.) This amendment becomes effective June 14, 1977. FOOTER:
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