AD 87-26-02 R1

final rule

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

AD Number
87-26-02 R1
Status
final_rule
Effective Date
Product Category
aircraft
Docket
87-SW-39-AD
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 (MBB) Model BO-105 Series Helicopters
aircraft Airbus Helicopters Deutschland GmbH BO-105C Airworthiness Directives; MESSERSCHMITT-BOLKOW-BLOHM (MBB) Model BO-105 Series Helicopters
aircraft Airbus Helicopters Deutschland GmbH BO-105LS A-1 Airworthiness Directives; MESSERSCHMITT-BOLKOW-BLOHM (MBB) Model BO-105 Series Helicopters
aircraft Airbus Helicopters Deutschland GmbH BO-105LS A-3 Airworthiness Directives; MESSERSCHMITT-BOLKOW-BLOHM (MBB) Model BO-105 Series Helicopters
aircraft Airbus Helicopters Deutschland GmbH BO-105S Airworthiness Directives; MESSERSCHMITT-BOLKOW-BLOHM (MBB) Model BO-105 Series Helicopters

Unsafe Condition

Fatigue cracks in the threads of the main rotor pitch links rod ends, P/N's 105-13141.01 and 105-13142.01, could result in failure of the main rotor control system.

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

Required Actions

Check main rotor control rods for binding of spherical bearings before first flight daily. Within 50 hours' time in service after the effective date, inspect rod ends for cracks and corrosion via fluorescent magnetic particle or dye penetrant methods. Replace cracked or corroded rod ends before further flight. Repeat inspections after each bearing replacement.

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

Compliance Time

Before further flight for cracked or corroded rod ends. Initial inspection required within 50 hours' time in service after the effective date of this AD.

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

Affected Aircraft

Messerschmitt-Bolkow-Blohm (MBB) Model BO-105A, BO-105C, BO-105LS A-1, BO-105LS A-3, BO-105S helicopters equipped with main rotor blade rotating control rod ends, P/N's 105-13141.01 and 105-13142.01.

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

Federal Register Abstract

Main Rotor Control Rods

Applicability Source Text

Show captured applicability text from the source AD
AD Final Rules - DRS_87-26-02_R.html
Copy URL
Print/Save as PDF
Document Versions
 Feedback
Details
AD Number:
87-26-02 R1
Document Type:
AD Final Rules
Docket Number:
87-SW-39-AD
Subject Heading:
Airworthiness Directives; MESSERSCHMITT-BOLKOW-BLOHM (MBB) Model BO-105 Series Helicopters
Subject:
Main Rotor Control Rods
Status:
Current
Citation:
This information is not available.
Citation Publish Date:
Effective Date:
09/26/1989
Make:
Airbus Helicopters Deutschland GmbH
Model:
BO-105A | BO-105C | BO-105LS A-1 | BO-105LS A-3 | 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: 87-26-02 R1
CITATION:   This information is not available.

PAGE NUMBER:  

DOCKET NUMBER:   87-SW-39-AD

AMENDMENT:   39-6313

AD NUMBER:   87-26-02 R1

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

ACTION:  

SUMMARY:  

DATES:   Effective September 26, 1989.

ADDRESSES:  

FOR FURTHER INFORMATION CONTACT:  

SUPPLEMENTARY INFORMATION:  

REGULATORY TEXT:  
87-26-02 R1 MESSERSCHMITT-BOLKOW-BLOHM (MBB): Amendment 39-5795 as revised by Amendment 39-6313. (Docket No. 87-SW-39-AD)

Applicability: Model BO-105 series helicopters, certificated in any category, equipped with main rotor blade rotating control rod ends, P/N's 105-13141.01 and 105-13142.01.

Compliance: Required as indicated unless already accomplished.

To detect and prevent fatigue cracks in the threads of the main rotor pitch links rod ends, accomplish the following:

(a) Before the first flight of each day after the effective date of this AD, check the main rotor control rods for binding of the spherical bearings as follows:

(1) Check the bearings on each control rod by rotating the rod about its longitudinal axis by hand. This check may be conducted by the pilot and must be recorded in accordance with Section 43.9.

NOTE: The pilot, when complying, must make appropriate entries and the record must be maintained per Section 91.173 or Section 135.439.

(2) Inspect and rework control rods containing a binding bearing in accordance with paragraphs (b)(1) through (b)(7) before further use.

(b) Within the next 50 hours' time in service after the effective date of this AD, conduct the following main rotor control rod inspection for cracks and spherical bearing torque determination:

(1) Remove the control rods from the helicopter.

(2) Remove the rod ends from the control rods.

(3) Measure the force required to rotate the inner race of the rod end bearings in the circumferential direction around a bolt centerline (ref. figure No.1).

(4) If the bearing torque (force X moment arm) required to rotate the bearing inner race is more than 1.5 NM (13.3 in-lbs), accomplish either of the following--

(i) Replace the affected bearing and repeat the step in paragraph (b)(3); or

(ii) Reduce the bearing friction by installing a bolt through the bearing inner race and tighten with a nut. Then, using a drill, spin the bearing at 60 to 100 RPM for 1- or 2-minute periods until friction torque is reduced to 1.5 NM (13.3 in-lbs) or below. Monitor temperature constantly to avoid overheating. (Bearing axial and radial play is not allowed.)

(5) Inspect the rod end threads as follows:

(i) Wrap the spherical bearing and rod in suitable adhesive tape to prevent cleaning solvent and wet developer from entering the bearing (ref. figure No.2).

(ii) Remove residual sealing compound, grease, and dirt from the threaded area of the rod ends.

(iii) Visually inspect the threaded area of the rod ends for corrosion.

(iv) Inspect the threaded area of the rod ends for cracks by fluorescent magnetic particle or fluorescent dye penetrant inspection methods.

(6) Replace before further flight any rod ends found to be cracked or corroded. Install serviceable parts.

NOTE: Operators are asked to submit rod ends removed as a result of this AD to MBB, Department LV52, together with the helicopter serial number, flight hours, and service time, if known.

(7) Install serviceable main rotor control rods in accordance with the applicable maintenance manual instructions.

NOTE: MBB ASB No. BO-105-10-103 dated October 28, 1987, pertains to this inspection and rework.

(c) Repeat the inspections of paragraphs (b)(3) through (b)(6) after each rod end bearing replacement.

(d) Report pitch link cracks by the inspections of paragraph (b) of this AD to the Manager, Aircraft Certification Division, Federal Aviation Administration, Fort Worth, Texas 76193-0100 within 10 days of the inspection. Provide aircraft serial number, total time, and time since the last pitch link rework, if any. [Reporting is approved by the Office of Management and Budget under OMB No. 2120-1156.]

(e) Upon request of the operator, an FAA Maintenance Inspector, subject to prior approval of the Manager, Aircraft Certification Division, Federal Aviation Administration, Southwest Region, may adjust the repetitive inspection intervals specified in this AD to permit compliance at an established inspection period if the request contains substantiating data to justify the increase for that operator.

(f) An alternate method of compliance which provides an equivalent level of safety with the requirements of this AD may be used when approved by the Manager, Aircraft Certification Division, Federal Aviation Administration, Fort Worth, Texas 76193-0100 or by the Manager, Aircraft Certification Staff, AEU-100, Federal Aviation Administration, Europe, Africa, and Middle East Office, c/o American Embassy, Brussels, Belgium, APO NY 09667.

(g) In accordance with FAR Section 21.197 and 21.199, flight is permitted to a base where the inspections required by this AD may be accomplished.

This amendment (39-6313) revises Amendment 39-5795 (52 FR 46991; December 11, 1987), AD 87-26-02, which became effective on December 31, 1987.

This amendment (39-6313, AD 87-26-02 R1) becomes effective on September 26, 1989.



BEARING FRICTION MEASUREMENT
FIGURE NO. 1
AD 87-26-02 R1




ROD END WITH BEARING TAPED

FIGURE NO. 2
AD 87-26-02 R1


FOOTER:

Document Text

Show stored source text (verify against official source)
AD Final Rules - DRS_87-26-02_R.html
Copy URL
Print/Save as PDF
Document Versions
 Feedback
Details
AD Number:
87-26-02 R1
Document Type:
AD Final Rules
Docket Number:
87-SW-39-AD
Subject Heading:
Airworthiness Directives; MESSERSCHMITT-BOLKOW-BLOHM (MBB) Model BO-105 Series Helicopters
Subject:
Main Rotor Control Rods
Status:
Current
Citation:
This information is not available.
Citation Publish Date:
Effective Date:
09/26/1989
Make:
Airbus Helicopters Deutschland GmbH
Model:
BO-105A | BO-105C | BO-105LS A-1 | BO-105LS A-3 | 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: 87-26-02 R1
CITATION:   This information is not available.

PAGE NUMBER:  

DOCKET NUMBER:   87-SW-39-AD

AMENDMENT:   39-6313

AD NUMBER:   87-26-02 R1

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

ACTION:  

SUMMARY:  

DATES:   Effective September 26, 1989.

ADDRESSES:  

FOR FURTHER INFORMATION CONTACT:  

SUPPLEMENTARY INFORMATION:  

REGULATORY TEXT:  
87-26-02 R1 MESSERSCHMITT-BOLKOW-BLOHM (MBB): Amendment 39-5795 as revised by Amendment 39-6313. (Docket No. 87-SW-39-AD)

Applicability: Model BO-105 series helicopters, certificated in any category, equipped with main rotor blade rotating control rod ends, P/N's 105-13141.01 and 105-13142.01.

Compliance: Required as indicated unless already accomplished.

To detect and prevent fatigue cracks in the threads of the main rotor pitch links rod ends, accomplish the following:

(a) Before the first flight of each day after the effective date of this AD, check the main rotor control rods for binding of the spherical bearings as follows:

(1) Check the bearings on each control rod by rotating the rod about its longitudinal axis by hand. This check may be conducted by the pilot and must be recorded in accordance with Section 43.9.

NOTE: The pilot, when complying, must make appropriate entries and the record must be maintained per Section 91.173 or Section 135.439.

(2) Inspect and rework control rods containing a binding bearing in accordance with paragraphs (b)(1) through (b)(7) before further use.

(b) Within the next 50 hours' time in service after the effective date of this AD, conduct the following main rotor control rod inspection for cracks and spherical bearing torque determination:

(1) Remove the control rods from the helicopter.

(2) Remove the rod ends from the control rods.

(3) Measure the force required to rotate the inner race of the rod end bearings in the circumferential direction around a bolt centerline (ref. figure No.1).

(4) If the bearing torque (force X moment arm) required to rotate the bearing inner race is more than 1.5 NM (13.3 in-lbs), accomplish either of the following--

(i) Replace the affected bearing and repeat the step in paragraph (b)(3); or

(ii) Reduce the bearing friction by installing a bolt through the bearing inner race and tighten with a nut. Then, using a drill, spin the bearing at 60 to 100 RPM for 1- or 2-minute periods until friction torque is reduced to 1.5 NM (13.3 in-lbs) or below. Monitor temperature constantly to avoid overheating. (Bearing axial and radial play is not allowed.)

(5) Inspect the rod end threads as follows:

(i) Wrap the spherical bearing and rod in suitable adhesive tape to prevent cleaning solvent and wet developer from entering the bearing (ref. figure No.2).

(ii) Remove residual sealing compound, grease, and dirt from the threaded area of the rod ends.

(iii) Visually inspect the threaded area of the rod ends for corrosion.

(iv) Inspect the threaded area of the rod ends for cracks by fluorescent magnetic particle or fluorescent dye penetrant inspection methods.

(6) Replace before further flight any rod ends found to be cracked or corroded. Install serviceable parts.

NOTE: Operators are asked to submit rod ends removed as a result of this AD to MBB, Department LV52, together with the helicopter serial number, flight hours, and service time, if known.

(7) Install serviceable main rotor control rods in accordance with the applicable maintenance manual instructions.

NOTE: MBB ASB No. BO-105-10-103 dated October 28, 1987, pertains to this inspection and rework.

(c) Repeat the inspections of paragraphs (b)(3) through (b)(6) after each rod end bearing replacement.

(d) Report pitch link cracks by the inspections of paragraph (b) of this AD to the Manager, Aircraft Certification Division, Federal Aviation Administration, Fort Worth, Texas 76193-0100 within 10 days of the inspection. Provide aircraft serial number, total time, and time since the last pitch link rework, if any. [Reporting is approved by the Office of Management and Budget under OMB No. 2120-1156.]

(e) Upon request of the operator, an FAA Maintenance Inspector, subject to prior approval of the Manager, Aircraft Certification Division, Federal Aviation Administration, Southwest Region, may adjust the repetitive inspection intervals specified in this AD to permit compliance at an established inspection period if the request contains substantiating data to justify the increase for that operator.

(f) An alternate method of compliance which provides an equivalent level of safety with the requirements of this AD may be used when approved by the Manager, Aircraft Certification Division, Federal Aviation Administration, Fort Worth, Texas 76193-0100 or by the Manager, Aircraft Certification Staff, AEU-100, Federal Aviation Administration, Europe, Africa, and Middle East Office, c/o American Embassy, Brussels, Belgium, APO NY 09667.

(g) In accordance with FAR Section 21.197 and 21.199, flight is permitted to a base where the inspections required by this AD may be accomplished.

This amendment (39-6313) revises Amendment 39-5795 (52 FR 46991; December 11, 1987), AD 87-26-02, which became effective on December 31, 1987.

This amendment (39-6313, AD 87-26-02 R1) becomes effective on September 26, 1989.



BEARING FRICTION MEASUREMENT
FIGURE NO. 1
AD 87-26-02 R1




ROD END WITH BEARING TAPED

FIGURE NO. 2
AD 87-26-02 R1


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.