AD 85-23-51 R1

final rule

Airworthiness Directives; BOEING VERTOL COMPANY Model 234 Series Helicopters

AD Number
85-23-51 R1
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 Columbia Helicopters, Inc. 234 Airworthiness Directives; BOEING VERTOL COMPANY Model 234 Series Helicopters

Unsafe Condition

Cracked main rotor head vertical hinge pins, P/N 114R2172-1, could cause possible hazards in flight.

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

Required Actions

Conduct a visual inspection using a light-assisted bore-scope for cracks on forward and aft main rotor head vertical hinge pins (P/N 114R2172-1) prior to further flight. Repeat daily inspections until replaced. Perform an eddy current inspection within 150 hours time in service from March 31, 1986, and a magnetic particle inspection within 500 hours time in service from the same date. Replace cracked pins before further flight.

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

Compliance Time

Prior to further flight, within the next 150 hours time in service from March 31, 1986, and within the next 500 hours time in service from March 31, 1986.

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

Affected Aircraft

Boeing Vertol Model 234 series helicopters certificated in any category.

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

Federal Register Abstract

Main Rotor Head Vertical Hinge Pins Inspection

Applicability Source Text

Show captured applicability text from the source AD
AD Final Rules - DRS_85-23-51_R.html
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AD Number:
85-23-51 R1
Document Type:
AD Final Rules
Docket Number:
Unknown
Subject Heading:
Airworthiness Directives; BOEING VERTOL COMPANY Model 234 Series Helicopters
Subject:
Main Rotor Head Vertical Hinge Pins Inspection
Status:
Current
Citation:
This information is not available.
Citation Publish Date:
Effective Date:
03/31/1986
Make:
Columbia Helicopters, Inc.
Model:
234
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Superseded AD: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Superseded By: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: 85-23-51 R1
CITATION:   This information is not available.

PAGE NUMBER:  

DOCKET NUMBER:   Unknown

AMENDMENT:   39-5253

AD NUMBER:   85-23-51 R1

SUBJECT HEADING:   Airworthiness Directives; BOEING VERTOL COMPANY Model 234 Series Helicopters

ACTION:  

SUMMARY:  

DATES:   Effective March 31, 1986.

ADDRESSES:  

FOR FURTHER INFORMATION CONTACT:  

SUPPLEMENTARY INFORMATION:  

REGULATORY TEXT:  
85-23-51 R1 BOEING VERTOL COMPANY: Amendment 39-5253. Applies to Boeing Vertol Model 234 series helicopters certificated in any category.

Compliance is required as indicated unless already accomplished.

To prevent possible hazards in flight associated with a cracked main rotor head vertical hinge pin, accomplish the following:

(a) Prior to further flight, conduct a visual inspection of the forward and aft main rotor head vertical hinge pins, P/N 114R2172-1, internal surface with a light assisted bore-scope for cracks.

(b) After the initial inspection of paragraph (a), repeat the inspection prior to the first flight of each day.

(c) Within the next 150 hours time in service from March 31, 1986, conduct an eddy current inspection of the internal surfaces of the forward and aft main rotor head vertical hinge pins, P/N 114R2172-1, in accordance with the instructions contained in Boeing Vertol Document D210-12089-1 titled "Eddy Current Inspection Requirements for Detection of Cracks in P/N 114R2172, Vertical Hinge Pins." Upon accomplishment of this paragraph, the daily bore-scope inspection of paragraph (b) may be eliminated.

(d) Within the next 500 hours time in service from March 31, 1986, remove from the helicopter the main rotor head vertical hinge pins and conduct a magnetic particle inspection in accordance with Boeing Airplane Company document BAC 5424 titled "Magnetic Particle Inspection" Class B.

(e) Remove from service vertical hinge pins found cracked and replace with a serviceable part prior to further flight.

(f) Any alternate method of compliance with the AD which provides an equivalent level of safety may be used when approved by the Manager, New York Aircraft Certification Office, Federal Aviation Administration, 181 South Franklin Avenue, Valley Stream, New York 11581.

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 Boeing Vertol Company, Boeing Center, P.O. Box 1858, Philadelphia, Pennsylvania 19142. These documents may also be examined at the Office of the Regional Counsel, FAA Southwest Region, Federal Aviation Administration, 4400 Blue Mound Road, Fort Worth, Texas 76106.

This amendment becomes effective March 31, 1986, as to all persons except those to whom it was made immediately effective by telegraphic AD T85-23-51 issued November 20, 1985, which contained part of this amendment.

FOOTER:

Document Text

Show stored source text (verify against official source)
AD Final Rules - DRS_85-23-51_R.html
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Print/Save as PDF
Document Versions
 Feedback
Details
AD Number:
85-23-51 R1
Document Type:
AD Final Rules
Docket Number:
Unknown
Subject Heading:
Airworthiness Directives; BOEING VERTOL COMPANY Model 234 Series Helicopters
Subject:
Main Rotor Head Vertical Hinge Pins Inspection
Status:
Current
Citation:
This information is not available.
Citation Publish Date:
Effective Date:
03/31/1986
Make:
Columbia Helicopters, Inc.
Model:
234
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: 85-23-51 R1
CITATION:   This information is not available.

PAGE NUMBER:  

DOCKET NUMBER:   Unknown

AMENDMENT:   39-5253

AD NUMBER:   85-23-51 R1

SUBJECT HEADING:   Airworthiness Directives; BOEING VERTOL COMPANY Model 234 Series Helicopters

ACTION:  

SUMMARY:  

DATES:   Effective March 31, 1986.

ADDRESSES:  

FOR FURTHER INFORMATION CONTACT:  

SUPPLEMENTARY INFORMATION:  

REGULATORY TEXT:  
85-23-51 R1 BOEING VERTOL COMPANY: Amendment 39-5253. Applies to Boeing Vertol Model 234 series helicopters certificated in any category.

Compliance is required as indicated unless already accomplished.

To prevent possible hazards in flight associated with a cracked main rotor head vertical hinge pin, accomplish the following:

(a) Prior to further flight, conduct a visual inspection of the forward and aft main rotor head vertical hinge pins, P/N 114R2172-1, internal surface with a light assisted bore-scope for cracks.

(b) After the initial inspection of paragraph (a), repeat the inspection prior to the first flight of each day.

(c) Within the next 150 hours time in service from March 31, 1986, conduct an eddy current inspection of the internal surfaces of the forward and aft main rotor head vertical hinge pins, P/N 114R2172-1, in accordance with the instructions contained in Boeing Vertol Document D210-12089-1 titled "Eddy Current Inspection Requirements for Detection of Cracks in P/N 114R2172, Vertical Hinge Pins." Upon accomplishment of this paragraph, the daily bore-scope inspection of paragraph (b) may be eliminated.

(d) Within the next 500 hours time in service from March 31, 1986, remove from the helicopter the main rotor head vertical hinge pins and conduct a magnetic particle inspection in accordance with Boeing Airplane Company document BAC 5424 titled "Magnetic Particle Inspection" Class B.

(e) Remove from service vertical hinge pins found cracked and replace with a serviceable part prior to further flight.

(f) Any alternate method of compliance with the AD which provides an equivalent level of safety may be used when approved by the Manager, New York Aircraft Certification Office, Federal Aviation Administration, 181 South Franklin Avenue, Valley Stream, New York 11581.

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 Boeing Vertol Company, Boeing Center, P.O. Box 1858, Philadelphia, Pennsylvania 19142. These documents may also be examined at the Office of the Regional Counsel, FAA Southwest Region, Federal Aviation Administration, 4400 Blue Mound Road, Fort Worth, Texas 76106.

This amendment becomes effective March 31, 1986, as to all persons except those to whom it was made immediately effective by telegraphic AD T85-23-51 issued November 20, 1985, which contained part of this amendment.

FOOTER:

Source: Official FAA Source ↗

Retrieved: Apr 8, 2026

Rights: U.S. Government Public Domain

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