AD 84-18-04

final rule

Airworthiness Directives; ROBINSON HELICOPTER COMPANY Model R-22 Series Helicopters

AD Number
84-18-04
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 Robinson Helicopter Company R22 Airworthiness Directives; ROBINSON HELICOPTER COMPANY Model R-22 Series Helicopters
aircraft Robinson Helicopter Company R22 ALPHA Airworthiness Directives; ROBINSON HELICOPTER COMPANY Model R-22 Series Helicopters

Unsafe Condition

Main rotor gearbox failure due to bolt failure (including head separation) on the underside of the ring gear.

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

Required Actions

Within 15 hours time in service after the effective date, inspect all 12 bolt heads on the underside of the ring gear. If bolt failure is observed, replace the gearbox before further flight. If no failure is found, reinstall the sight glass. Additionally, within 200 hours time in service, modify the gearbox with Robinson Kit No. KI-37 to discontinue inspections. If the oil chip detector illuminates, perform the inspection before further flight.

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

Compliance Time

Within the next 15 hours time in service after the effective date of this AD, unless already accomplished within the last 35 hours time in service, and thereafter at intervals not to exceed 50 hours time in service from the last inspection. The modification must be done within the next 200 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

Robinson Helicopter Company Model R-22 series helicopters with main rotor gearbox Part Number A006-1, Revision A through V.

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

Federal Register Abstract

Main Rotor Gearbox

Applicability Source Text

Show captured applicability text from the source AD
AD Final Rules - DRS_84-18-04.html
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AD Number:
84-18-04
Document Type:
AD Final Rules
Docket Number:
Unknown
Subject Heading:
Airworthiness Directives; ROBINSON HELICOPTER COMPANY Model R-22 Series Helicopters
Subject:
Main Rotor Gearbox
Status:
Current
Citation:
This information is not available.
Citation Publish Date:
Effective Date:
11/08/1986
Make:
Robinson Helicopter Company
Model:
R22 | R22 ALPHA
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: 84-18-04
CITATION:   This information is not available.

PAGE NUMBER:  

DOCKET NUMBER:   Unknown

AMENDMENT:   39-4948

AD NUMBER:   84-18-04

SUBJECT HEADING:   Airworthiness Directives; ROBINSON HELICOPTER COMPANY Model R-22 Series Helicopters

ACTION:  

SUMMARY:  

DATES:   Effective November 8, 1986.

ADDRESSES:  

FOR FURTHER INFORMATION CONTACT:  

SUPPLEMENTARY INFORMATION:  

REGULATORY TEXT:  
84-18-04 ROBINSON HELICOPTER COMPANY: Amendment 39-4948. Applies to Model R-22 series helicopters certificated in all categories having main rotor gearbox Part Number A006-1, Revision A through V, installed.

Compliance required as indicated unless already accomplished.

To prevent main rotor gearbox failure, accomplish the following:

(a) Within the next 15 hours time in service after the effective date of this AD, unless already accomplished within the last 35 hours time in service, and thereafter at intervals not to exceed 50 hours time in service from the last inspection:

(1) Remove the oil level sight glass from the main rotor gearbox.

NOTE: To prevent oil loss the right skid may be elevated.

(2) Manually rotate the drive system and visually inspect all 12 bolt heads located on underside of ring gear using suitable illumination.

(3) If any bolt failure is observed (including head separation), replace the gearbox with a serviceable gearbox before further flight.

(4) If no indication of bolt failure is observed, reinstall sight glass in accordance with normal maintenance instructions.

(b) If the main rotor gearbox oil chip detector illuminates during ground or flight operation, in addition to normal maintenance procedures, comply with paragraph (a) before further flight.

(c) Within the next 200 hours time in service after the effective date of this AD, modify the main rotor gearbox to include Robinson Kit No. KI-37 in accordance with Instructions No. KI-37 dated August 24, 1984. When this modification has been accomplished, the inspections required by Paragraph (a) may be discontinued.

NOTE: Robinson Service Bulletin No. 43, dated August 24, 1984, pertains to this subject.

(d) The helicopter may be flown under the provisions of FAR Sections 21.197 and 21.199 to a base where the inspections and modification of paragraphs (a) and (c) may be accomplished, provided the gearbox oil chip detector has not illuminated.

(e) Alternative means of compliance providing an equivalent level of safety with this AD may be used when approved by the Manager, Western Aircraft Certification Office, FAA, Northwest Mountain Region.

This amendment becomes effective November 8, 1984, as to all persons except those persons to whom it was made immediately effective by priority letter AD 84-18-04 issued September 6, 1984, which contained this amendment.

FOOTER:

Document Text

Show stored source text (verify against official source)
AD Final Rules - DRS_84-18-04.html
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Print/Save as PDF
Document Versions
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Details
AD Number:
84-18-04
Document Type:
AD Final Rules
Docket Number:
Unknown
Subject Heading:
Airworthiness Directives; ROBINSON HELICOPTER COMPANY Model R-22 Series Helicopters
Subject:
Main Rotor Gearbox
Status:
Current
Citation:
This information is not available.
Citation Publish Date:
Effective Date:
11/08/1986
Make:
Robinson Helicopter Company
Model:
R22 | R22 ALPHA
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: 84-18-04
CITATION:   This information is not available.

PAGE NUMBER:  

DOCKET NUMBER:   Unknown

AMENDMENT:   39-4948

AD NUMBER:   84-18-04

SUBJECT HEADING:   Airworthiness Directives; ROBINSON HELICOPTER COMPANY Model R-22 Series Helicopters

ACTION:  

SUMMARY:  

DATES:   Effective November 8, 1986.

ADDRESSES:  

FOR FURTHER INFORMATION CONTACT:  

SUPPLEMENTARY INFORMATION:  

REGULATORY TEXT:  
84-18-04 ROBINSON HELICOPTER COMPANY: Amendment 39-4948. Applies to Model R-22 series helicopters certificated in all categories having main rotor gearbox Part Number A006-1, Revision A through V, installed.

Compliance required as indicated unless already accomplished.

To prevent main rotor gearbox failure, accomplish the following:

(a) Within the next 15 hours time in service after the effective date of this AD, unless already accomplished within the last 35 hours time in service, and thereafter at intervals not to exceed 50 hours time in service from the last inspection:

(1) Remove the oil level sight glass from the main rotor gearbox.

NOTE: To prevent oil loss the right skid may be elevated.

(2) Manually rotate the drive system and visually inspect all 12 bolt heads located on underside of ring gear using suitable illumination.

(3) If any bolt failure is observed (including head separation), replace the gearbox with a serviceable gearbox before further flight.

(4) If no indication of bolt failure is observed, reinstall sight glass in accordance with normal maintenance instructions.

(b) If the main rotor gearbox oil chip detector illuminates during ground or flight operation, in addition to normal maintenance procedures, comply with paragraph (a) before further flight.

(c) Within the next 200 hours time in service after the effective date of this AD, modify the main rotor gearbox to include Robinson Kit No. KI-37 in accordance with Instructions No. KI-37 dated August 24, 1984. When this modification has been accomplished, the inspections required by Paragraph (a) may be discontinued.

NOTE: Robinson Service Bulletin No. 43, dated August 24, 1984, pertains to this subject.

(d) The helicopter may be flown under the provisions of FAR Sections 21.197 and 21.199 to a base where the inspections and modification of paragraphs (a) and (c) may be accomplished, provided the gearbox oil chip detector has not illuminated.

(e) Alternative means of compliance providing an equivalent level of safety with this AD may be used when approved by the Manager, Western Aircraft Certification Office, FAA, Northwest Mountain Region.

This amendment becomes effective November 8, 1984, as to all persons except those persons to whom it was made immediately effective by priority letter AD 84-18-04 issued September 6, 1984, which contained this amendment.

FOOTER:

Source: Official FAA Source ↗

Retrieved: Apr 8, 2026

Rights: U.S. Government Public Domain

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