AD 75-14-02
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Airbus Helicopters Deutschland GmbH | BO-105A | Airworthiness Directives; Messerschmitt Boelkow Blohm (MBB) Model BO-105 Helicopters |
| aircraft | Airbus Helicopters Deutschland GmbH | BO-105C | Airworthiness Directives; Messerschmitt Boelkow Blohm (MBB) Model BO-105 Helicopters |
Unsafe Condition
Failure in service of main rotor hub quadruple nuts due to cracks resulting from manufacturing defects.
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Required Actions
Determine the production lot number of the installed main rotor hub quadruple nuts (P/N 105-14101.19 and .20) within twenty hours time in service after the effective date. If the lot number is 06, 07, or cannot be determined, remove and replace the quadruple nuts with serviceable parts of the same part number before further flight.
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Compliance Time
within twenty hours time in service after the effective date
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Affected Aircraft
Messerschmitt Boelkow Blohm (MBB) Model BO-105A and BO-105C helicopters certificated in all categories.
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Federal Register Abstract
Rotor Hub Quadruple Nuts
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_75-14-02.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 75-14-02 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Messerschmitt Boelkow Blohm (MBB) Model BO-105 Helicopters Subject: Rotor Hub Quadruple Nuts Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: Make: Airbus Helicopters Deutschland GmbH Model: BO-105A | BO-105C Product Type: Aircraft Product Subtype: Rotorcraft Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: Updated RGL applicability to match AD applicability; CAR C-11-185 AIRWORTHINESS DIRECTIVES FINAL RULES: 75-14-02 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-2246 AD NUMBER: 75-14-02 SUBJECT HEADING: Airworthiness Directives; Messerschmitt Boelkow Blohm (MBB) Model BO-105 Helicopters ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 75-14-02 MESSERSCHMITT BOELKOW BLOHM GMBH: Amendment 39-2246. Applies to Messerschmitt Boelkow Blohm (MBB) Model BO-105 Helicopters certificated in all categories. Compliance is required as indicated. To prevent failure in service of certain main rotor hub quadruple nuts due to cracks resulting from manufacturing defects, accomplish the following: (a) Within the next twenty hours time in service after the effective date of this AD, determine the production lot number of the two installed main rotor hub quadruple nuts, P/N 105- 14101.19 and .20. NOTE: Quadruple nuts are identified "VIERFACHNUSS" on P/N drawings. Production lot number of nuts is set forth as first two digits of serial number recorded in MBB individual aircraft historical record document, under the heading of Main Rotor Head Assembly No. 105-14101. (b) If the lot number determined in accordance with paragraph (a) of this AD is 06 or 07, or if the lot number cannot be determined, before further flight, except that the aircraft may be flown in accordance with FAR Section 21.197 and 21.199 to a base where the work can be performed, remove the two quadruple nuts and replace with serviceable parts of the same part number. (Messerschmitt Boelkow Blohn BO-105 Alert Service Bulletin No. 9 covers this same subject). This amendment is effective upon publication in the Federal Register as to all persons except those persons to whom it was made immediately effective by the telegram dated May 14, 1975, which contained this amendment. FOOTER:
Document Text
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AD Final Rules - DRS_75-14-02.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 75-14-02 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Messerschmitt Boelkow Blohm (MBB) Model BO-105 Helicopters Subject: Rotor Hub Quadruple Nuts Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: Make: Airbus Helicopters Deutschland GmbH Model: BO-105A | BO-105C 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: Updated RGL applicability to match AD applicability; CAR C-11-185 AIRWORTHINESS DIRECTIVES FINAL RULES: 75-14-02 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-2246 AD NUMBER: 75-14-02 SUBJECT HEADING: Airworthiness Directives; Messerschmitt Boelkow Blohm (MBB) Model BO-105 Helicopters ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 75-14-02 MESSERSCHMITT BOELKOW BLOHM GMBH: Amendment 39-2246. Applies to Messerschmitt Boelkow Blohm (MBB) Model BO-105 Helicopters certificated in all categories. Compliance is required as indicated. To prevent failure in service of certain main rotor hub quadruple nuts due to cracks resulting from manufacturing defects, accomplish the following: (a) Within the next twenty hours time in service after the effective date of this AD, determine the production lot number of the two installed main rotor hub quadruple nuts, P/N 105- 14101.19 and .20. NOTE: Quadruple nuts are identified "VIERFACHNUSS" on P/N drawings. Production lot number of nuts is set forth as first two digits of serial number recorded in MBB individual aircraft historical record document, under the heading of Main Rotor Head Assembly No. 105-14101. (b) If the lot number determined in accordance with paragraph (a) of this AD is 06 or 07, or if the lot number cannot be determined, before further flight, except that the aircraft may be flown in accordance with FAR Section 21.197 and 21.199 to a base where the work can be performed, remove the two quadruple nuts and replace with serviceable parts of the same part number. (Messerschmitt Boelkow Blohn BO-105 Alert Service Bulletin No. 9 covers this same subject). This amendment is effective upon publication in the Federal Register as to all persons except those persons to whom it was made immediately effective by the telegram dated May 14, 1975, which contained this amendment. FOOTER:
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