MANDATORY MANDATORY MANDATORY

MANDATORY MANDATORY MANDATORY

SERVICE BULLETIN

Copyright 1999-2010 by MD Helicopters Inc.

This document may be reproduced and distributed provided no fee is charged,

the text is not modified, and this copyright notice is included.

TAIL ROTOR BLADE ASSEMBLY INSPECTION

1. PLANNING INFORMATION

A. Aircraft Affected:

All MD Helicopters, Inc. (MDHI) Model 369A (Army OH-6A), 369H, 369HE, 369HS,

369HM, 369D, 369E, 369F, and 369FF, and tail rotor blade assemblies in spares inventory.

B. Assembly/Components Affected By This Notice:

Tail Rotor Blade Assembly MDHI P/N 369D21640-501 and -503

Helicopter Technology Co. (HTC) HTC P/N 500P3100-101 to include “M”, “MT”, “I” and “IT”

Tail Rotor Blade Assembly MDHI P/N 369D21641-501 and -503

Helicopter Technology Co. (HTC) HTC P/N 500P3100-301 to include “M”, “MT”, “I” and “IT”

Tail Rotor Blade Assembly MDHI P/N 369D21643-501 and -503

Helicopter Technology Co. (HTC) HTC P/N 500P3300-501 to include “M”, “MT”, “I” and “IT”

Tail Rotor Blade Assembly MDHI P/N 369D21642-501 and -503

Helicopter Technology Co. (HTC) HTC P/N 500P3500-701 to include “M”, “MT”, “I” and “IT”

C. Reason:

Failure to comply with this bulletin can result in the pitch control arm separating from the

tail rotor blade. This will lead to an unbalanced condition, vibration, partial loss of tail

rotor pitch control and possible loss of directional control of the helicopter.

D. Description:

Procedures in this Bulletin give owners and operators information that pertains to an

inspection of the tail rotor blade assembly pitch control arm for any evidence of corrosion,

corrosion pitting or cracks.

E. Time of Compliance:

Perform this Bulletin within five (5) flight hours of receiving this Bulletin. Remove Tail

Rotor Blade Assembly, strip paint and inspect each pitch control arm (all four sides and the

pocket) for corrosion, corrosion pitting or cracks in the hatched areas shown in Figure 1 of

this Bulletin.

F. FAA Approval:

The technical design aspects of this Bulletin are FAA Approved.

G. Manpower:

Corrosion Inspection: Five and one-half (5.5) man-hours.

H. Interchangeability:

None.

I. Points of Contact:

For further assistance, contact the Field Service Department at MDHI, Mesa, Arizona.

Telephone 1-800-388-3378 or 480-346-6387. DATAFAX: 480-346-6813.

SB369D-210 SB369E-105

SB369F-091 SB369H-252

DATE: 21 NOVEMBER 2011

PAGE 1 OF 6
MANDATORY MANDATORY MANDATORY

MANDATORY MANDATORY MANDATORY

SERVICE BULLETIN

Copyright 1999-2010 by MD Helicopters Inc.

This document may be reproduced and distributed provided no fee is charged,

the text is not modified, and this copyright notice is included.

J. Material/Part Availability:

Contact MDHI Field Service Department.

REPLACEMENT PARTS/SUPPLIES 

Nomenclature Part No. Qty. Source

Tail Rotor Blade Assembly 369D21640−507 AR MDHI

Tail Rotor Blade Assembly 369D21641−507 AR MDHI

Tail Rotor Blade Assembly 369D21642−507 AR MDHI

Tail Rotor Blade Assembly 369D21643−507 AR MDHI

Tail Rotor Blade Assembly 500P3100−305 AR HTC

Tail Rotor Blade Assembly 500P3300−505 AR HTC

Tail Rotor Blade Assembly 500P3500−705 AR HTC

Paint Stripper Turco #5351 1 Henkel

Aluminum Tape 

(0.005 thick 2.0 width)

MIL-T-23399 1 3M

Alodine Alodine 1201 1 Henkel

K. Warranty Policy:

N/A

L. Tooling:

Magnifying Glass, 10X minimum - commercial

Bright Light Source - commercial

TOOLS AND EQUIPMENT 

Nomenclature Source

Magnifying Glass 10X Commercial

Bright Light Source Commercial

SB369D-210 SB369E-105

SB369F-091 SB369H-252

DATE: 21 NOVEMBER 2011

PAGE 2 OF 6
MANDATORY MANDATORY MANDATORY

MANDATORY MANDATORY MANDATORY

SERVICE BULLETIN

Copyright 1999-2010 by MD Helicopters Inc.

This document may be reproduced and distributed provided no fee is charged,

the text is not modified, and this copyright notice is included.

M. Weight and Balance:

N/A

N. Electrical Load Data:

N/A

O. Other Publications Affected:

CSP-HMI-2 Basic Handbook of Maintenance Instructions - Servicing and Maintenance

CSP-H-2 Basic Handbook of Maintenance Instructions

CSP-H-4, Appendix B - Airworthiness Limitations Overhaul and Replacement Schedules

Periodic Inspections Weight and Balance Procedures

P. Reference Publications:

Refer to the latest revision of these publications for procedures and additional information:

CSP-HMI-2 Basic Handbook of Maintenance Instructions - Servicing and Maintenance

CSP-H-2 Basic Handbook of Maintenance Instructions

AD 2003-08-51 issued April 15, 2003

AMOC June 13, 2003 for AD 2003-08-51

HTC Service Bulletin 3100-5 - Tail Rotor Blade Pitch Control Arm Corrosion Inspection

2. ACCOMPLISHMENT INSTRUCTIONS

(Ref. Figure 1)

A. Corrosion Inspection

(1). Remove tail rotor blade assembly (Ref. CSP-HMI-2, Section 64-10-00, or 

CSP-H-2, Section 8).

Use care when handling pitch bearings. Teflon reinforced linings are easily damaged

if mishandled or exposed to contaminants. If lining is damaged or contaminated,

bearing service life will be shortened or bearing replacement may be required.

(2). (Ref. Figure 1, Note 2). Carefully tape around bearing, bushing and blade areas to

prevent contamination from debris and paint stripper. Use aluminum tape that is

resistant to paint stripper.

Extreme care shall be taken to prevent debris or paint stripper contamination in

bearing and bushing areas and tail rotor blade bond surfaces and cavities.

(3). Remove paint from tail rotor blade pitch control arm (all four sides and the pocket) as

shown in Figure 1 with paint stripper. (Ref. CSP-HMI-2, Section 20-30-00 or 

CSP-H-2, Section 2).

SB369D-210 SB369E-105

SB369F-091 SB369H-252

DATE: 21 NOVEMBER 2011

PAGE 3 OF 6

CAUTION

CAUTION
MANDATORY MANDATORY MANDATORY

MANDATORY MANDATORY MANDATORY

SERVICE BULLETIN

Copyright 1999-2010 by MD Helicopters Inc.

This document may be reproduced and distributed provided no fee is charged,

the text is not modified, and this copyright notice is included.

The pitch control arm area is shot peened and has a protective chemical coating. No

abrasive cleaning, sanding or blending is allowed.

(4). (Ref. Figure 1 hatched area). Use a bright light and 10X magnifying glass to inspect the

tail rotor blade pitch control arm (all four sides and the pocket) for corrosion, corrosion

pitting or cracks. No corrosion, corrosion pitting or cracks are allowed. If corrosion,

corrosion pitting or cracks are present, replace blade assembly before next flight. (Ref.

CSP-HMI-2, Section 64-10-00 or CSP-H-2, Section 8). Mark the defective tail rotor

blade assembly as scrap and destroy.

(5). Make sure the inspection area has a “dimpled” shot peen surface texture. If the inspection area surface is not shot peened or there is evidence of blending or material removal

that affected the shot peened surface, replace blade assembly before next flight. (Ref.

CSP-HMI-2, Section 64-10-00 or CSP-H-2, Section 8). In addition, check rotorcraft

maintenance records to make sure no rework was done in this area. Mark the defective

tail rotor blade assembly as scrap and destroy.

(6). If no corrosion, corrosion pitting or cracks exist and the inspection area has an acceptable shot peen surface texture, refinish stripped pitch control arm as follows:

(a). Apply alodine per instructions contained in the CSP-HMI-2, Section 20-40-00 or

CSP-H-2, Section 2).

(b). Apply primer and paint to match original as required (Ref. CSP-HMI-2, Section

20-30-00 or CSP-H-2, Section 2).

(7). Install tail rotor blade assembly (Ref CSP-HMI-2, Section 64-10-00 or 

CSP-H-2, Section 8).

B. Compliance Record

(1). Record compliance to this Service Bulletin in the Compliance Record section of the

Rotorcraft Log Book and the tail rotor blade assembly component card.

(2). Complete Bulletin Completed Record form (attached) and FAX or e-mail to MDHI Field

Service Department.

C. Periodic Inspection

Upon completion of this Bulletin, perform yearly inspections of pitch control arm per

CSP-HMI-2, Section 05-20-15 or CSP-H-4, Section 05-20-15.

SB369D-210 SB369E-105

SB369F-091 SB369H-252

DATE: 21 NOVEMBER 2011

PAGE 4 OF 6

CAUTION
MANDATORY MANDATORY MANDATORY

MANDATORY MANDATORY MANDATORY

SERVICE BULLETIN

Copyright 1999-2010 by MD Helicopters Inc.

This document may be reproduced and distributed provided no fee is charged,

the text is not modified, and this copyright notice is included.

ROTATED

A

A

SECTION A-A

64-001

NOTE 1

NOTE 1

PITCH CONTROL ARM

NOTE 2

NOTE 2

NOTES:

1. REMOVE PAINT FROM ALL FOUR (4) SIDES OF PITCH CONTROL ARM.

2. PROTECT AREAS FROM PAINT STRIPPER, ALODINE AND PAINT.

Figure 1. Tail Rotor Pitch Control Arm

SB369D-210 SB369E-105

SB369F-091 SB369H-252

DATE: 21 NOVEMBER 2011

PAGE 5 OF 6
MANDATORY MANDATORY MANDATORY

MANDATORY MANDATORY MANDATORY

SERVICE BULLETIN

Copyright 1999-2010 by MD Helicopters Inc.

This document may be reproduced and distributed provided no fee is charged,

the text is not modified, and this copyright notice is included.

Bulletin Completed Record

TAIL ROTOR BLADE ASSEMBLY INSPECTION

MD Helicopters, Inc.

Field Service Department

4555 E. McDowell Road

Mesa, AZ 85215−9734

800−388−3378 Phone (U.S. and Canada)

480−346−6387 Phone (International)

480−346−6813 Fax

FAX this form to MDHI (480) 346−6813 or E−mail to ServiceEngineering@mdhelicopters.com

Owner

/Operator:

Helicopter

Serial No:

Address:

Helicopter

Total Time:

Tail Rotor Blade

P/N:

S/N:

Date Complete:

Phone: Location:

E−mail:

This bulletin is complete:

(Signature)

(Print Name)

(Title)

Comments: 

SB369D-210 SB369E-105

SB369F-091 SB369H-252

DATE: 21 NOVEMBER 2011

PAGE 6 OF 6