AD 88-17-09 R1

final rule

Airworthiness Directives; MCDONNELL DOUGLAS HELICOPTER COMPANY (MDHC) (HUGHES HELICOPTERS, INC.) Model 369D, E, F, and FF Helicopters

AD Number
88-17-09 R1
Status
final_rule
Effective Date
Product Category
aircraft
Docket
88-ASW-24
FR Citation
This information is not available.
Technical illustration of a helicopter rotor hub assembly
Problem area Rotor system

Applicability

TypeManufacturerModelDetails
aircraft MD Helicopters, Inc. 369D Airworthiness Directives; MCDONNELL DOUGLAS HELICOPTER COMPANY (MDHC) (HUGHES HELICOPTERS, INC.) Model 369D, E, F, and FF Helicopters
aircraft MD Helicopters, Inc. 369E Airworthiness Directives; MCDONNELL DOUGLAS HELICOPTER COMPANY (MDHC) (HUGHES HELICOPTERS, INC.) Model 369D, E, F, and FF Helicopters
aircraft MD Helicopters, Inc. 369F Airworthiness Directives; MCDONNELL DOUGLAS HELICOPTER COMPANY (MDHC) (HUGHES HELICOPTERS, INC.) Model 369D, E, F, and FF Helicopters
aircraft MD Helicopters, Inc. 369FF Airworthiness Directives; MCDONNELL DOUGLAS HELICOPTER COMPANY (MDHC) (HUGHES HELICOPTERS, INC.) Model 369D, E, F, and FF Helicopters

Unsafe Condition

Failure of the tail rotor transmission mounting studs (P/N MS51992A803-13 or -14) on MDHC Model 369 D/E helicopters or failure of the tail boom extension mounting studs (P/N MS51992A803-13 or -14) on MDHC Model 369 F/FF helicopters due to relative motion between the parts.

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

Required Actions

Conduct initial inspections prior to further flight after the effective date, followed by checks at intervals not exceeding 25 hours' time in service. Replace studs if relative motion is found and perform repetitive torque inspections every 100 hours' time in service. Follow MDHC SIN DN-151/EN-39/FN-28 procedures.

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

Compliance Time

Prior to further flight after the effective date of this AD, and within the next 25 hours' time in service after the effective date for subsequent checks.

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

Affected Aircraft

MCDONNELL DOUGLAS HELICOPTER COMPANY (MDHC) (HUGHES HELICOPTERS, INC.) Model 369D, E, F, and FF helicopters with tail rotor transmission/tail boom extension mounting studs Part Number MS51992A803-13 or -14 installed.

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

Federal Register Abstract

Tail Rotor Transmission

Applicability Source Text

Show captured applicability text from the source AD
AD Final Rules - DRS_88-17-09_R.html
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AD Number:
88-17-09 R1
Document Type:
AD Final Rules
Docket Number:
88-ASW-24
Subject Heading:
Airworthiness Directives; MCDONNELL DOUGLAS HELICOPTER COMPANY (MDHC) (HUGHES HELICOPTERS, INC.) Mo...Show more
Subject:
Tail Rotor Transmission
Status:
Current
Citation:
This information is not available.
Citation Publish Date:
Effective Date:
12/26/1989
Make:
MD Helicopters, Inc.
Model:
369D | 369E | 369F | 369FF
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:
AIRWORTHINESS DIRECTIVES FINAL RULES: 88-17-09 R1
CITATION:   This information is not available.

PAGE NUMBER:  

DOCKET NUMBER:   88-ASW-24

AMENDMENT:   39-6400

AD NUMBER:   88-17-09 R1

SUBJECT HEADING:   Airworthiness Directives; MCDONNELL DOUGLAS HELICOPTER COMPANY (MDHC) (HUGHES HELICOPTERS,
INC.) Model 369D, E, F, and FF Helicopters


ACTION:  

SUMMARY:  

DATES:   Effective December 26, 1989.

ADDRESSES:  

FOR FURTHER INFORMATION CONTACT:  

SUPPLEMENTARY INFORMATION:  

REGULATORY TEXT:  
88-17-09 R1 MCDONNELL DOUGLAS HELICOPTER COMPANY (MDHC) (HUGHES HELICOPTERS, INC.): Amendment 39-5964 as revised by Amendment 39-6400. Docket No. 88-ASW-24.

Applicability: Model 369D, E, F, and FF helicopters, certificated in any category, which have tail rotor transmission/tail boom extension mounting studs, Part Number (P/N) MS51992A803-13 or -14, installed.

Compliance: Required as indicated, unless already accomplished.

(a) To prevent failure of the tail rotor transmission mounting studs (P/N MS51992A803-13 or -14) on MDHC Model 369 D/E helicopters, accomplish the following:

(1) Prior to further flight after the effective date of this AD, conduct an initial inspection of the tail rotor transmission attachment to the tail boom casting for any indications of relative motion between the parts in accordance with MDHC Service Information Notice (SIN) DN-151/EN-39/FN-28, Part I, paragraphs a, b, c, d, and e, dated October 10, 1987.

(2) Within the next 25 hours' time in service after the effective date of this amended AD, and at intervals not to exceed 25 hours' time in service from the last check, conduct a check for security in accordance with MDHC SIN DN-151/EN-39/FN-28, Part II, paragraph a, dated October 10, 1987. The checks required by this paragraph may be performed by the pilot and must be recorded in accordance with FAR Section 43.9.

(3) If there are indications of relative motion between the tail rotor transmission and the tail boom casting found by the inspection and check of paragraphs (a)(1) and (a)(2), prior to further flight, remove the tail rotor transmission and replace all four mounting studs in accordance with MDHC SIN DN-151/EN-39/FN-28, Part III, paragraphs a thru j, dated October 10, 1987.

(4) At intervals not to exceed 100 hours' time in service from the last inspection after the effective date of this AD, conduct repetitive inspections of the torque of each mounting nut and reapply torque stripe paint in accordance with MDHC SIN DN-151/EN-39/FN- 28, Part IV, paragraphs a and b, dated October 10, 1987.

(b) To prevent failure of the tail boom extension mounting studs (P/N MS51992A803-13 or -14) on MDHC Model 369 F/FF helicopters, accomplish the following:

(1) Prior to further flight after the effective date of this AD, conduct an initial inspection of the tail boom extension attachment to the tail boom casting for any indications of relative motion between the parts in accordance with MDHC SIN DN-151/EN- 39/FN-28, Part I, paragraphs a, b, c, d, and e, dated October 10, 1987.

(2) Within the next 25 hours' time in service after the effective date of this amended AD, and at intervals not to exceed 25 hours' time in service from the last check, conduct a check of the tail boom extension installation for security in accordance with MDHC SIN DN- 151/EN-39/FN-28, Part II, paragraph a, dated October 10, 1987. The checks required by this paragraph may be performed by the pilot and must be recorded in accordance with FAR Section 43.9.

(3) If there are indications of relative motion of fretting products between the tail boom casting and the tail boom extension found by the above inspections or checks, prior to further flight, remove tail boom extension and replace all four studs in accordance with MDHC SIN DN-151/EN-39/FN-28, Part III, paragraphs b thru j, dated October 10, 1987.

(4) At intervals not to exceed 100 hours' time in service from the last inspection after the effective date of this AD, conduct repetitive inspections of the torque of each mounting nut and reapply torque stripe paint in accordance with MDHC SIN DN-151/EN-39/FN- 28, Part IV, paragraphs a and b, dated October 10, 1987.

(c) An alternate means of compliance which provides an equivalent level of safety may be used when approved by the Manager, Western Aircraft Certification Office, P.O. Box 92007, Worldway Postal Center, Los Angeles, CA 90009-2007.

(d) In accordance with Sections 21.197 and 21.199, the helicopters may be flown to a base where compliance may be accomplished.

These inspections and check procedures shall be done in accordance with MDHC Mandatory SIN DN-151/EN-39/FN-28, dated October 10, 1987. This incorporation by reference was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR Part 51. Copies may be obtained from MDHC Technical Publications, Building 543/D214, McDonnell Douglas Helicopter Company, 5000 E. McDowell Road, Mesa, Arizona 85205-9797, telephone (602) 891-6484. A copy may also be inspected at the Office of the Assistant Chief Counsel, Federal Aviation Administration, 4400 Blue Mound Road, Room 158, Building 3B, Fort Worth, Texas, or at the Office of the Federal Register, 1100 L Street NW, Room 8401, Washington, D.C.

This AD revises Amendment 39-5964 (53 FR 30023; August 10, 1988), AD 88-17-09, which became effective on August 24, 1988.

This amendment (39-6400, AD 88-17-09 R1) becomes effective on December 26, 1989.

FOOTER:

Document Text

Show stored source text (verify against official source)
AD Final Rules - DRS_88-17-09_R.html
Copy URL
Print/Save as PDF
Document Versions
 Feedback
Details
AD Number:
88-17-09 R1
Document Type:
AD Final Rules
Docket Number:
88-ASW-24
Subject Heading:
Airworthiness Directives; MCDONNELL DOUGLAS HELICOPTER COMPANY (MDHC) (HUGHES HELICOPTERS, INC.) Mo...Show more
Subject:
Tail Rotor Transmission
Status:
Current
Citation:
This information is not available.
Citation Publish Date:
Effective Date:
12/26/1989
Make:
MD Helicopters, Inc.
Model:
369D | 369E | 369F | 369FF
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:
AIRWORTHINESS DIRECTIVES FINAL RULES: 88-17-09 R1
CITATION:   This information is not available.

PAGE NUMBER:  

DOCKET NUMBER:   88-ASW-24

AMENDMENT:   39-6400

AD NUMBER:   88-17-09 R1

SUBJECT HEADING:   Airworthiness Directives; MCDONNELL DOUGLAS HELICOPTER COMPANY (MDHC) (HUGHES HELICOPTERS,
INC.) Model 369D, E, F, and FF Helicopters


ACTION:  

SUMMARY:  

DATES:   Effective December 26, 1989.

ADDRESSES:  

FOR FURTHER INFORMATION CONTACT:  

SUPPLEMENTARY INFORMATION:  

REGULATORY TEXT:  
88-17-09 R1 MCDONNELL DOUGLAS HELICOPTER COMPANY (MDHC) (HUGHES HELICOPTERS, INC.): Amendment 39-5964 as revised by Amendment 39-6400. Docket No. 88-ASW-24.

Applicability: Model 369D, E, F, and FF helicopters, certificated in any category, which have tail rotor transmission/tail boom extension mounting studs, Part Number (P/N) MS51992A803-13 or -14, installed.

Compliance: Required as indicated, unless already accomplished.

(a) To prevent failure of the tail rotor transmission mounting studs (P/N MS51992A803-13 or -14) on MDHC Model 369 D/E helicopters, accomplish the following:

(1) Prior to further flight after the effective date of this AD, conduct an initial inspection of the tail rotor transmission attachment to the tail boom casting for any indications of relative motion between the parts in accordance with MDHC Service Information Notice (SIN) DN-151/EN-39/FN-28, Part I, paragraphs a, b, c, d, and e, dated October 10, 1987.

(2) Within the next 25 hours' time in service after the effective date of this amended AD, and at intervals not to exceed 25 hours' time in service from the last check, conduct a check for security in accordance with MDHC SIN DN-151/EN-39/FN-28, Part II, paragraph a, dated October 10, 1987. The checks required by this paragraph may be performed by the pilot and must be recorded in accordance with FAR Section 43.9.

(3) If there are indications of relative motion between the tail rotor transmission and the tail boom casting found by the inspection and check of paragraphs (a)(1) and (a)(2), prior to further flight, remove the tail rotor transmission and replace all four mounting studs in accordance with MDHC SIN DN-151/EN-39/FN-28, Part III, paragraphs a thru j, dated October 10, 1987.

(4) At intervals not to exceed 100 hours' time in service from the last inspection after the effective date of this AD, conduct repetitive inspections of the torque of each mounting nut and reapply torque stripe paint in accordance with MDHC SIN DN-151/EN-39/FN- 28, Part IV, paragraphs a and b, dated October 10, 1987.

(b) To prevent failure of the tail boom extension mounting studs (P/N MS51992A803-13 or -14) on MDHC Model 369 F/FF helicopters, accomplish the following:

(1) Prior to further flight after the effective date of this AD, conduct an initial inspection of the tail boom extension attachment to the tail boom casting for any indications of relative motion between the parts in accordance with MDHC SIN DN-151/EN- 39/FN-28, Part I, paragraphs a, b, c, d, and e, dated October 10, 1987.

(2) Within the next 25 hours' time in service after the effective date of this amended AD, and at intervals not to exceed 25 hours' time in service from the last check, conduct a check of the tail boom extension installation for security in accordance with MDHC SIN DN- 151/EN-39/FN-28, Part II, paragraph a, dated October 10, 1987. The checks required by this paragraph may be performed by the pilot and must be recorded in accordance with FAR Section 43.9.

(3) If there are indications of relative motion of fretting products between the tail boom casting and the tail boom extension found by the above inspections or checks, prior to further flight, remove tail boom extension and replace all four studs in accordance with MDHC SIN DN-151/EN-39/FN-28, Part III, paragraphs b thru j, dated October 10, 1987.

(4) At intervals not to exceed 100 hours' time in service from the last inspection after the effective date of this AD, conduct repetitive inspections of the torque of each mounting nut and reapply torque stripe paint in accordance with MDHC SIN DN-151/EN-39/FN- 28, Part IV, paragraphs a and b, dated October 10, 1987.

(c) An alternate means of compliance which provides an equivalent level of safety may be used when approved by the Manager, Western Aircraft Certification Office, P.O. Box 92007, Worldway Postal Center, Los Angeles, CA 90009-2007.

(d) In accordance with Sections 21.197 and 21.199, the helicopters may be flown to a base where compliance may be accomplished.

These inspections and check procedures shall be done in accordance with MDHC Mandatory SIN DN-151/EN-39/FN-28, dated October 10, 1987. This incorporation by reference was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR Part 51. Copies may be obtained from MDHC Technical Publications, Building 543/D214, McDonnell Douglas Helicopter Company, 5000 E. McDowell Road, Mesa, Arizona 85205-9797, telephone (602) 891-6484. A copy may also be inspected at the Office of the Assistant Chief Counsel, Federal Aviation Administration, 4400 Blue Mound Road, Room 158, Building 3B, Fort Worth, Texas, or at the Office of the Federal Register, 1100 L Street NW, Room 8401, Washington, D.C.

This AD revises Amendment 39-5964 (53 FR 30023; August 10, 1988), AD 88-17-09, which became effective on August 24, 1988.

This amendment (39-6400, AD 88-17-09 R1) becomes effective on December 26, 1989.

FOOTER:

Source: Official FAA Source ↗

Retrieved: Apr 8, 2026

Rights: U.S. Government Public Domain

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