AD 85-26-02

final rule

Airworthiness Directives; MESSERSCHMITT-BOLKOW-BLOHM Model BO-105 Series Helicopters

AD Number
85-26-02
Status
final_rule
Effective Date
Product Category
aircraft
Docket
Unknown
FR Citation
This information is not available.
Technical illustration of a helicopter rotor hub assembly
Problem area Rotor system

Applicability

TypeManufacturerModelDetails
aircraft Airbus Helicopters Deutschland GmbH BO-105A Airworthiness Directives; MESSERSCHMITT-BOLKOW-BLOHM Model BO-105 Series Helicopters
aircraft Airbus Helicopters Deutschland GmbH BO-105C Airworthiness Directives; MESSERSCHMITT-BOLKOW-BLOHM Model BO-105 Series Helicopters
aircraft Airbus Helicopters Deutschland GmbH BO-105S Airworthiness Directives; MESSERSCHMITT-BOLKOW-BLOHM Model BO-105 Series Helicopters

Unsafe Condition

Jamming of the helicopter main rotor control system due to binding of the System II hydraulic actuators.

AI-generated summary from the source AD text. Verify against the official source before acting.

Required Actions

Before the first flight of each day after the effective date, operate the System II hydraulic actuators to detect binding. Within the next 10 hours time in service, clean and seal the actuators per MBB BO-105 ASB No. 26 Part 2B or equivalent. After sealing, the daily operational check is no longer required.

AI-generated summary from the source AD text. Verify against the official source before acting.

Compliance Time

Before the first flight of each day after the effective date and within the next 10 hours time in service after the effective date.

AI-generated summary from the source AD text. Verify against the official source before acting.

Affected Aircraft

MESSERSCHMITT-BOLKOW-BLOHM Model BO-105A, BO-105C, BO-105S helicopters through serial No. 750 equipped with tandem hydraulic units having Part Numbers 105-45021, 105-45023, 105-45028, 105-83001, 105-83011, D133-3073, or DSK1-30142.

AI-generated summary from the source AD text. Verify against the official source before acting.

Federal Register Abstract

Hydraulic Actuator

Applicability Source Text

Show captured applicability text from the source AD
AD Final Rules - DRS_85-26-02.html
Copy URL
Print/Save as PDF
Document Versions
 Feedback
Details
AD Number:
85-26-02
Document Type:
AD Final Rules
Docket Number:
Unknown
Subject Heading:
Airworthiness Directives; MESSERSCHMITT-BOLKOW-BLOHM Model BO-105 Series Helicopters
Subject:
Hydraulic Actuator
Status:
Current
Citation:
This information is not available.
Citation Publish Date:
Effective Date:
02/25/1986
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: 85-26-02
CITATION:   This information is not available.

PAGE NUMBER:  

DOCKET NUMBER:   Unknown

AMENDMENT:   39-5226

AD NUMBER:   85-26-02

SUBJECT HEADING:   Airworthiness Directives; MESSERSCHMITT-BOLKOW-BLOHM Model BO-105 Series Helicopters

ACTION:  

SUMMARY:  

DATES:   Effectives February 25, 1986.

ADDRESSES:  

FOR FURTHER INFORMATION CONTACT:  

SUPPLEMENTARY INFORMATION:  

REGULATORY TEXT:  
85-26-02 MESSERSCHMITT-BOLKOW-BLOHM: Amendment 39-5226. Applies to Model BO-105 series helicopters, through serial No. 750, certificated in any category that are equipped with one of the following tandem hydraulic units: Part Numbers (P/N) 105-45021, 105- 45023, 105-45028, 105-83001, 105-83011, D133-3073, and DSK1-30142.

Compliance is required as indicated, unless previously accomplished.

To detect or prevent possible jamming of the helicopter main rotor control system, accomplish the following:

(a) Before the first flight of each day after the effective date of this AD, operate the System II hydraulic actuators to detect binding of the control. If binding is detected, clean and seal the System II hydraulic actuators in accordance with paragraph (b) of this AD.

(b) Within the next 10 hours time in service after the effective date of this AD, clean and seal the System II hydraulic actuators in accordance with MBB BO-105, ASB No. 26, Part 2B, dated December 12, 1985, or with an equivalent approved in accordance with paragraph D of this AD. After sealing, the operational check in paragraph (a) is no longer required.

(c) The operational check in paragraph (a) may be performed by the pilot.

NOTE: For the requirements regarding recording compliance and method of compliance with this AD in the aircraft's permanent maintenance records, see FAR Section 91.173.

(d) Upon request, an equivalent means of compliance with this AD may be used when approved by the Manager, Aircraft Certification Office, FAA, Europe, Africa, and Middle East Office, c/o American Embassy, Brussels, Belgium, APO NY 09667-1011.

(e) The aircraft may be flown in accordance with FAR Sections 21.197 and 21.199 to a base where the actuators may be sealed in accordance with paragraph (b) of this AD.

The manufacturer's specifications and procedures identified and described in this directive are incorporated herein and made a part hereof pursuant to 5 U.S.C. 552(a)(1). All persons affected by this directive who have not already received these documents from the manufacturer may obtain copies upon request to MBB Helicopter Corp., P.O. Box 2349, West Chester, Pennsylvania 19380. These documents may also be examined at the Office of the Regional Counsel, Federal Aviation Administration, Southwest Region, Room 158, Building 3B, 4400 Blue Mound Road, Fort Worth, Texas 76106.

This amendment becomes effective February 25, 1986, as to all persons except those persons to whom it was made immediately effective by priority letter AD 85-26-02, issued December 23, 1985, which contained this amendment.

FOOTER:

Document Text

Show stored source text (verify against official source)
AD Final Rules - DRS_85-26-02.html
Copy URL
Print/Save as PDF
Document Versions
 Feedback
Details
AD Number:
85-26-02
Document Type:
AD Final Rules
Docket Number:
Unknown
Subject Heading:
Airworthiness Directives; MESSERSCHMITT-BOLKOW-BLOHM Model BO-105 Series Helicopters
Subject:
Hydraulic Actuator
Status:
Current
Citation:
This information is not available.
Citation Publish Date:
Effective Date:
02/25/1986
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: 85-26-02
CITATION:   This information is not available.

PAGE NUMBER:  

DOCKET NUMBER:   Unknown

AMENDMENT:   39-5226

AD NUMBER:   85-26-02

SUBJECT HEADING:   Airworthiness Directives; MESSERSCHMITT-BOLKOW-BLOHM Model BO-105 Series Helicopters

ACTION:  

SUMMARY:  

DATES:   Effectives February 25, 1986.

ADDRESSES:  

FOR FURTHER INFORMATION CONTACT:  

SUPPLEMENTARY INFORMATION:  

REGULATORY TEXT:  
85-26-02 MESSERSCHMITT-BOLKOW-BLOHM: Amendment 39-5226. Applies to Model BO-105 series helicopters, through serial No. 750, certificated in any category that are equipped with one of the following tandem hydraulic units: Part Numbers (P/N) 105-45021, 105- 45023, 105-45028, 105-83001, 105-83011, D133-3073, and DSK1-30142.

Compliance is required as indicated, unless previously accomplished.

To detect or prevent possible jamming of the helicopter main rotor control system, accomplish the following:

(a) Before the first flight of each day after the effective date of this AD, operate the System II hydraulic actuators to detect binding of the control. If binding is detected, clean and seal the System II hydraulic actuators in accordance with paragraph (b) of this AD.

(b) Within the next 10 hours time in service after the effective date of this AD, clean and seal the System II hydraulic actuators in accordance with MBB BO-105, ASB No. 26, Part 2B, dated December 12, 1985, or with an equivalent approved in accordance with paragraph D of this AD. After sealing, the operational check in paragraph (a) is no longer required.

(c) The operational check in paragraph (a) may be performed by the pilot.

NOTE: For the requirements regarding recording compliance and method of compliance with this AD in the aircraft's permanent maintenance records, see FAR Section 91.173.

(d) Upon request, an equivalent means of compliance with this AD may be used when approved by the Manager, Aircraft Certification Office, FAA, Europe, Africa, and Middle East Office, c/o American Embassy, Brussels, Belgium, APO NY 09667-1011.

(e) The aircraft may be flown in accordance with FAR Sections 21.197 and 21.199 to a base where the actuators may be sealed in accordance with paragraph (b) of this AD.

The manufacturer's specifications and procedures identified and described in this directive are incorporated herein and made a part hereof pursuant to 5 U.S.C. 552(a)(1). All persons affected by this directive who have not already received these documents from the manufacturer may obtain copies upon request to MBB Helicopter Corp., P.O. Box 2349, West Chester, Pennsylvania 19380. These documents may also be examined at the Office of the Regional Counsel, Federal Aviation Administration, Southwest Region, Room 158, Building 3B, 4400 Blue Mound Road, Fort Worth, Texas 76106.

This amendment becomes effective February 25, 1986, as to all persons except those persons to whom it was made immediately effective by priority letter AD 85-26-02, issued December 23, 1985, which contained this amendment.

FOOTER:

Source: Official FAA Source ↗

Retrieved: Apr 8, 2026

Rights: U.S. Government Public Domain

This site is not affiliated with or endorsed by the FAA. Always verify with official sources.