AD 79-24-06
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Airbus Helicopters Deutschland GmbH | BO-105A | Airworthiness Directives; Messerschmitt-Bolkow-Blohm Model BO-105 Helicopters |
| aircraft | Airbus Helicopters Deutschland GmbH | BO-105C | Airworthiness Directives; Messerschmitt-Bolkow-Blohm Model BO-105 Helicopters |
| aircraft | Airbus Helicopters Deutschland GmbH | BO-105S | Airworthiness Directives; Messerschmitt-Bolkow-Blohm Model BO-105 Helicopters |
Unsafe Condition
In-flight loss of tail rotor balance trim weights and consequent imbalance of the tail rotor blades.
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Required Actions
Inspect tail rotor blades within 10 hours time in service after the effective date, and daily thereafter until modifications are done. If cracks or bonding separation found, replace affected blade or both blades with improved designs. Modify balance provisions of blades per Service Bulletin or approved equivalent.
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Compliance Time
Within the next 10 hours time in service after the effective date of this AD, and thereafter following the last flight of each day upon which the accumulated time in service since the preceding inspection reaches 10 hours, until the modifications required by paragraph (c) of this AD are accomplished.
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Affected Aircraft
Messerschmitt-Bolkow-Blohm Model BO-105A, BO-105C, BO-105S helicopters with tail rotor blades P/N 105-31742 or P/N 105-87161 not modified per Alert Service Bulletin No. AB-16, Revision 1.
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Federal Register Abstract
Tail Rotor Blades
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_79-24-06.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 79-24-06 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Messerschmitt-Bolkow-Blohm Model BO-105 Helicopters Subject: Tail Rotor Blades Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 12/10/1979 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Deutschland GmbH Model: BO-105A | BO-105C | BO-105S Product Type: Aircraft Product Subtype: Rotorcraft Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: Updated RGL applicability to match AD applicability; CAR C-11-185 AIRWORTHINESS DIRECTIVES FINAL RULES: 79-24-06 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-3622 AD NUMBER: 79-24-06 SUBJECT HEADING: Airworthiness Directives; Messerschmitt-Bolkow-Blohm Model BO-105 Helicopters ACTION: SUMMARY: DATES: Effective December 10, 1979. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 79-24-06 MESSERSCHMITT-BOLKOW-BLOHM GmbH: Amendment 39-3622. Applies to all Model BO-105 helicopters, certificated in any category, incorporating tail rotor blades P/N 105-31742 or P/N 105-87161 that have not been modified in accordance with the Accomplishment Instructions, paragraph 2.B., of Messerschmitt-Bolkow-Blohm Alert Service Bulletin No. AB-16, Revision 1, dated December 22, 1978, hereinafter referred to as the Service Bulletin, or an FAA-approved equivalent. Compliance required as indicated. To prevent in-flight loss of tail rotor balance trim weights, and consequent imbalance of the tail rotor blades, accomplished the following: (a) Within the next 10 hours time in service after the effective date of this AD, and thereafter following the last flight of each day upon which the accumulated time in service since the preceding inspection reaches 10 hours, until the modifications required by paragraph (c) of this AD are accomplished, inspect the tail rotor blades for condition in accordance with paragraph 2.A. of the Accomplishment Instructions of the Service Bulletin, or an FAA-approved equivalent. (b) If the inspection required by paragraph (a) of this AD reveals any cracks, or bonding separation that is unacceptable in accordance with the inspection criteria contained in paragraph 2.A. of the Service Bulletin, or an FAA-approved equivalent, before further flight, except that the helicopter may be flown in accordance with FAR 21.197 to a place where the required work can be performed - (1) Replace the affected blade with a serviceable blade of the same part number and continue to comply with the repetitive inspection and modification requirements of paragraph (a) and (c) of this AD; or (2) Replace both blades with blades of improved design, P/N 105-31743 or P/N 105-31744 after which paragraphs (a) and (c) of this AD do not apply. (See paragraph (d) of this AD.) (c) Within the next 100 hours time in service after the effective date of this AD, inspect the tail rotor blades in accordance with paragraph 2.A. of the Service Bulletin or an FAA-approved equivalent and before further flight - (1) If the inspection reveals any cracks, or bonding separation that is not acceptable in accordance with the inspection criteria contained in paragraph 2.A. of the Service Bulletin or an FAA-approved equivalent - (i) Replace the affected blade with a serviceable blade of the same part number and modify the tail rotor blade balance provisions of both blades in accordance with paragraph 2.B. of Accomplishment Instructions of the Service Bulletin or an FAA-approved equivalent; or (ii) Replace both blades with blades of improved design, P/N 105-31743 or P/N 105- 31744. (See paragraph (d) of this AD.) (2) If the inspection does not reveal any cracks or bonding separation that is not acceptable in accordance with the inspection criteria contained in paragraph 2.A. of the Service Bulletin or an FAA-approved equivalent, modify the tail rotor blade balance provisions of both blades in accordance with paragraph 2.B. of the Service Bulletin or an FAA-approved equivalent. (d) If tail rotor blades are to be changed in compliance with this AD, both blades must be of the same part number. (e) For the purpose of this AD, an FAA-approved equivalent must be approved by the Chief, Aircraft Certification Staff, AEU-100, FAA, Europe, Africa, and Middle East Region, c/o American Embassy, Brussels, Belgium. This amendment becomes effective December 10, 1979. FOOTER:
Document Text
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AD Final Rules - DRS_79-24-06.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 79-24-06 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Messerschmitt-Bolkow-Blohm Model BO-105 Helicopters Subject: Tail Rotor Blades Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 12/10/1979 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: Updated RGL applicability to match AD applicability; CAR C-11-185 AIRWORTHINESS DIRECTIVES FINAL RULES: 79-24-06 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-3622 AD NUMBER: 79-24-06 SUBJECT HEADING: Airworthiness Directives; Messerschmitt-Bolkow-Blohm Model BO-105 Helicopters ACTION: SUMMARY: DATES: Effective December 10, 1979. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 79-24-06 MESSERSCHMITT-BOLKOW-BLOHM GmbH: Amendment 39-3622. Applies to all Model BO-105 helicopters, certificated in any category, incorporating tail rotor blades P/N 105-31742 or P/N 105-87161 that have not been modified in accordance with the Accomplishment Instructions, paragraph 2.B., of Messerschmitt-Bolkow-Blohm Alert Service Bulletin No. AB-16, Revision 1, dated December 22, 1978, hereinafter referred to as the Service Bulletin, or an FAA-approved equivalent. Compliance required as indicated. To prevent in-flight loss of tail rotor balance trim weights, and consequent imbalance of the tail rotor blades, accomplished the following: (a) Within the next 10 hours time in service after the effective date of this AD, and thereafter following the last flight of each day upon which the accumulated time in service since the preceding inspection reaches 10 hours, until the modifications required by paragraph (c) of this AD are accomplished, inspect the tail rotor blades for condition in accordance with paragraph 2.A. of the Accomplishment Instructions of the Service Bulletin, or an FAA-approved equivalent. (b) If the inspection required by paragraph (a) of this AD reveals any cracks, or bonding separation that is unacceptable in accordance with the inspection criteria contained in paragraph 2.A. of the Service Bulletin, or an FAA-approved equivalent, before further flight, except that the helicopter may be flown in accordance with FAR 21.197 to a place where the required work can be performed - (1) Replace the affected blade with a serviceable blade of the same part number and continue to comply with the repetitive inspection and modification requirements of paragraph (a) and (c) of this AD; or (2) Replace both blades with blades of improved design, P/N 105-31743 or P/N 105-31744 after which paragraphs (a) and (c) of this AD do not apply. (See paragraph (d) of this AD.) (c) Within the next 100 hours time in service after the effective date of this AD, inspect the tail rotor blades in accordance with paragraph 2.A. of the Service Bulletin or an FAA-approved equivalent and before further flight - (1) If the inspection reveals any cracks, or bonding separation that is not acceptable in accordance with the inspection criteria contained in paragraph 2.A. of the Service Bulletin or an FAA-approved equivalent - (i) Replace the affected blade with a serviceable blade of the same part number and modify the tail rotor blade balance provisions of both blades in accordance with paragraph 2.B. of Accomplishment Instructions of the Service Bulletin or an FAA-approved equivalent; or (ii) Replace both blades with blades of improved design, P/N 105-31743 or P/N 105- 31744. (See paragraph (d) of this AD.) (2) If the inspection does not reveal any cracks or bonding separation that is not acceptable in accordance with the inspection criteria contained in paragraph 2.A. of the Service Bulletin or an FAA-approved equivalent, modify the tail rotor blade balance provisions of both blades in accordance with paragraph 2.B. of the Service Bulletin or an FAA-approved equivalent. (d) If tail rotor blades are to be changed in compliance with this AD, both blades must be of the same part number. (e) For the purpose of this AD, an FAA-approved equivalent must be approved by the Chief, Aircraft Certification Staff, AEU-100, FAA, Europe, Africa, and Middle East Region, c/o American Embassy, Brussels, Belgium. This amendment becomes effective December 10, 1979. FOOTER:
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