AD 80-21-09 R1
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Continental Copters, Inc. | Isenberg, Wilbur M. | McCreary, Gifton | Scotts-Bell 47 Inc | Teryjon Aviation, Inc. | OH-13H | Airworthiness Directives; BELL Model 47, H-13, OH-13, and TH-13T Series Helicopters |
| aircraft | Continental Copters, Inc. | Isenberg, Wilbur M. | McCreary, Gifton | Scotts-Bell 47 Inc | Teryjon Aviation, Inc. | OH-13E | Airworthiness Directives; BELL Model 47, H-13, OH-13, and TH-13T Series Helicopters |
| aircraft | Continental Copters, Inc. | Isenberg, Wilbur M. | McCreary, Gifton | Scotts-Bell 47 Inc | Teryjon Aviation, Inc. | 47 | Airworthiness Directives; BELL Model 47, H-13, OH-13, and TH-13T Series Helicopters |
| aircraft | Continental Copters, Inc. | Isenberg, Wilbur M. | McCreary, Gifton | Scotts-Bell 47 Inc | Teryjon Aviation, Inc. | 47B | Airworthiness Directives; BELL Model 47, H-13, OH-13, and TH-13T Series Helicopters |
| aircraft | Continental Copters, Inc. | Isenberg, Wilbur M. | McCreary, Gifton | Scotts-Bell 47 Inc | Teryjon Aviation, Inc. | 47B3 | Airworthiness Directives; BELL Model 47, H-13, OH-13, and TH-13T Series Helicopters |
| aircraft | Continental Copters, Inc. | Isenberg, Wilbur M. | McCreary, Gifton | Scotts-Bell 47 Inc | Teryjon Aviation, Inc. | 47D | Airworthiness Directives; BELL Model 47, H-13, OH-13, and TH-13T Series Helicopters |
| aircraft | Continental Copters, Inc. | Isenberg, Wilbur M. | McCreary, Gifton | Scotts-Bell 47 Inc | Teryjon Aviation, Inc. | 47D1 | Airworthiness Directives; BELL Model 47, H-13, OH-13, and TH-13T Series Helicopters |
| aircraft | Continental Copters, Inc. | Isenberg, Wilbur M. | McCreary, Gifton | Scotts-Bell 47 Inc | Teryjon Aviation, Inc. | 47E | Airworthiness Directives; BELL Model 47, H-13, OH-13, and TH-13T Series Helicopters |
| aircraft | Continental Copters, Inc. | Isenberg, Wilbur M. | McCreary, Gifton | Scotts-Bell 47 Inc | Teryjon Aviation, Inc. | 47G | Airworthiness Directives; BELL Model 47, H-13, OH-13, and TH-13T Series Helicopters |
| aircraft | Continental Copters, Inc. | Isenberg, Wilbur M. | McCreary, Gifton | Scotts-Bell 47 Inc | Teryjon Aviation, Inc. | 47G-2 | Airworthiness Directives; BELL Model 47, H-13, OH-13, and TH-13T Series Helicopters |
| aircraft | Continental Copters, Inc. | Isenberg, Wilbur M. | McCreary, Gifton | Scotts-Bell 47 Inc | Teryjon Aviation, Inc. | 47G-2A | Airworthiness Directives; BELL Model 47, H-13, OH-13, and TH-13T Series Helicopters |
| aircraft | Continental Copters, Inc. | Isenberg, Wilbur M. | McCreary, Gifton | Scotts-Bell 47 Inc | Teryjon Aviation, Inc. | 47G-2A-1 | Airworthiness Directives; BELL Model 47, H-13, OH-13, and TH-13T Series Helicopters |
| aircraft | Continental Copters, Inc. | Isenberg, Wilbur M. | McCreary, Gifton | Scotts-Bell 47 Inc | Teryjon Aviation, Inc. | 47G-3 | Airworthiness Directives; BELL Model 47, H-13, OH-13, and TH-13T Series Helicopters |
| aircraft | Continental Copters, Inc. | Isenberg, Wilbur M. | McCreary, Gifton | Scotts-Bell 47 Inc | Teryjon Aviation, Inc. | 47G-3B | Airworthiness Directives; BELL Model 47, H-13, OH-13, and TH-13T Series Helicopters |
| aircraft | Continental Copters, Inc. | Isenberg, Wilbur M. | McCreary, Gifton | Scotts-Bell 47 Inc | Teryjon Aviation, Inc. | 47G-3B-1 | Airworthiness Directives; BELL Model 47, H-13, OH-13, and TH-13T Series Helicopters |
| aircraft | Continental Copters, Inc. | Isenberg, Wilbur M. | McCreary, Gifton | Scotts-Bell 47 Inc | Teryjon Aviation, Inc. | 47G-3B-2 | Airworthiness Directives; BELL Model 47, H-13, OH-13, and TH-13T Series Helicopters |
| aircraft | Continental Copters, Inc. | Isenberg, Wilbur M. | McCreary, Gifton | Scotts-Bell 47 Inc | Teryjon Aviation, Inc. | 47G-3B-2A | Airworthiness Directives; BELL Model 47, H-13, OH-13, and TH-13T Series Helicopters |
| aircraft | Continental Copters, Inc. | Isenberg, Wilbur M. | McCreary, Gifton | Scotts-Bell 47 Inc | Teryjon Aviation, Inc. | 47G-4 | Airworthiness Directives; BELL Model 47, H-13, OH-13, and TH-13T Series Helicopters |
| aircraft | Continental Copters, Inc. | Isenberg, Wilbur M. | McCreary, Gifton | Scotts-Bell 47 Inc | Teryjon Aviation, Inc. | 47G-4A | Airworthiness Directives; BELL Model 47, H-13, OH-13, and TH-13T Series Helicopters |
| aircraft | Continental Copters, Inc. | Isenberg, Wilbur M. | McCreary, Gifton | Scotts-Bell 47 Inc | Teryjon Aviation, Inc. | 47G-5 | Airworthiness Directives; BELL Model 47, H-13, OH-13, and TH-13T Series Helicopters |
| aircraft | Continental Copters, Inc. | Isenberg, Wilbur M. | McCreary, Gifton | Scotts-Bell 47 Inc | Teryjon Aviation, Inc. | 47G-5A | Airworthiness Directives; BELL Model 47, H-13, OH-13, and TH-13T Series Helicopters |
| aircraft | Continental Copters, Inc. | Isenberg, Wilbur M. | McCreary, Gifton | Scotts-Bell 47 Inc | Teryjon Aviation, Inc. | 47H-1 | Airworthiness Directives; BELL Model 47, H-13, OH-13, and TH-13T Series Helicopters |
| aircraft | Continental Copters, Inc. | Isenberg, Wilbur M. | McCreary, Gifton | Scotts-Bell 47 Inc | Teryjon Aviation, Inc. | 47J | Airworthiness Directives; BELL Model 47, H-13, OH-13, and TH-13T Series Helicopters |
| aircraft | Continental Copters, Inc. | Isenberg, Wilbur M. | McCreary, Gifton | Scotts-Bell 47 Inc | Teryjon Aviation, Inc. | 47J-2 | Airworthiness Directives; BELL Model 47, H-13, OH-13, and TH-13T Series Helicopters |
| aircraft | Continental Copters, Inc. | Isenberg, Wilbur M. | McCreary, Gifton | Scotts-Bell 47 Inc | Teryjon Aviation, Inc. | 47J-2A | Airworthiness Directives; BELL Model 47, H-13, OH-13, and TH-13T Series Helicopters |
| aircraft | Continental Copters, Inc. | Isenberg, Wilbur M. | McCreary, Gifton | Scotts-Bell 47 Inc | Teryjon Aviation, Inc. | 47K | Airworthiness Directives; BELL Model 47, H-13, OH-13, and TH-13T Series Helicopters |
| aircraft | Continental Copters, Inc. | Isenberg, Wilbur M. | McCreary, Gifton | Scotts-Bell 47 Inc | Teryjon Aviation, Inc. | Fast Kat I (U.S. Army OH-13S) | Airworthiness Directives; BELL Model 47, H-13, OH-13, and TH-13T Series Helicopters |
Unsafe Condition
Tail rotor pitch link failure could result in loss of directional control.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Remove the tail rotor pitch link from each blade pitch horn, inspect bearings for play, replace bearings with .015 inch or more of play, install specified bolts and washers with torque and cotter pins, and verify no binding in controls and track blades if bearings or links are replaced.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
within 100 hours' time in service after November 17, 1980
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
BELL Model 47 series helicopters and military Model H-13, OH-13, and TH-13T series helicopters equipped with 47-641-170 series tail rotor hub and blade assemblies
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Tail Rotor Pitch Link
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_80-21-09_R.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 80-21-09 R1 Document Type: AD Final Rules Docket Number: 80-ASW-29 Subject Heading: Airworthiness Directives; BELL Model 47, H-13, OH-13, and TH-13T Series Helicopters Subject: Tail Rotor Pitch Link Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 11/24/1980 Make: Continental Copters, Inc. | Isenberg, Wilbur M. | McCreary, Gifton | Scotts-Bell 47 Inc | Teryjon Av...Show more Model: OH-13H | OH-13E | 47 | 47B | 47B3 | 47D | 47D1 | 47E | 47G | 47G-2 | 47G-2A | 47G-2A-1 | 47G-3 | 47G...Show more 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: 80-21-09 R1 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: 80-ASW-29 AMENDMENT: 39-3976 AD NUMBER: 80-21-09 R1 SUBJECT HEADING: Airworthiness Directives; BELL Model 47, H-13, OH-13, and TH-13T Series Helicopters ACTION: SUMMARY: DATES: DATE: Effective November 24, 1980. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 80-21-09 R1 BELL: Amendment 39-3942 as amended by amendment 39-3976. Applies to all Model 47 series helicopters and military Model H-13, OH-13, and TH-13T series helicopters, including modified versions, certificated in all categories, that are equipped with the 47-641-170 series tail rotor hub and blade assemblies (Airworthiness Docket No. 80-ASW-29). Compliance required within 100 hours' time in service after November 17, 1980. To prevent loss of directional control as a result of possible tail rotor pitch link failure, accomplish the following, unless already accomplished in accordance with Bell Helicopter Textron Alert Service Bulletin No. 47-80-5, Rev. A, dated April 29, 1980. (a) Remove the tail rotor pitch link from each blade pitch horn. (b) Inspect the pitch link bearings for axial and radial play. Remove bearings having .015 inch or more of play or looseness, and install serviceable bearings. (c) Install bolts P/N NAS1304-32D or 20-057-4-32D (used with pitch horn, P/N 47-641-187-1, -3, or -5), or P/N NAS1304-30D, or 20-057-4-30D (used with pitch horn, P/N 47-641-187-7) as appropriate, with washer, P/N 47-641-189-1 or -3 under the bolt head or nut, and washer P/N 47-641-189-3 between the link bearing and pitch horn with bevel towards the bearing. Torque nuts 80 to 100 inch-pounds and install cotter pins. (d) Determine that no binding or interference occurs in the blade controls when the tail rotor controls are full left and right, and the tail rotor hub is flapped to each stop. Track the tail rotor blades in accordance with the appropriate Model 47 maintenance manual if a rod end bearing or a link is replaced in accordance with paragraph (b) of this AD. (e) Equivalent means of compliance with this AD may be approved by the Chief, Engineering and Manufacturing Branch, Flight Standards Division, FAA, Southwest Region. (Bell Helicopter Textron Operations Safety Notice OSN 47-79-1 dated October 19, 1979, also pertains to this subject.) Amendment 39-3942 became effective November 17, 1980. This amendment 39-3976 becomes effective November 24, 1980. FOOTER:
Document Text
Show stored source text (verify against official source)
AD Final Rules - DRS_80-21-09_R.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 80-21-09 R1 Document Type: AD Final Rules Docket Number: 80-ASW-29 Subject Heading: Airworthiness Directives; BELL Model 47, H-13, OH-13, and TH-13T Series Helicopters Subject: Tail Rotor Pitch Link Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 11/24/1980 Make: Continental Copters, Inc. | Isenberg, Wilbur M. | McCreary, Gifton | Scotts-Bell 47 Inc | Teryjon Av...Show more Model: OH-13H | OH-13E | 47 | 47B | 47B3 | 47D | 47D1 | 47E | 47G | 47G-2 | 47G-2A | 47G-2A-1 | 47G-3 | 47G...Show more 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: 80-21-09 R1 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: 80-ASW-29 AMENDMENT: 39-3976 AD NUMBER: 80-21-09 R1 SUBJECT HEADING: Airworthiness Directives; BELL Model 47, H-13, OH-13, and TH-13T Series Helicopters ACTION: SUMMARY: DATES: DATE: Effective November 24, 1980. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 80-21-09 R1 BELL: Amendment 39-3942 as amended by amendment 39-3976. Applies to all Model 47 series helicopters and military Model H-13, OH-13, and TH-13T series helicopters, including modified versions, certificated in all categories, that are equipped with the 47-641-170 series tail rotor hub and blade assemblies (Airworthiness Docket No. 80-ASW-29). Compliance required within 100 hours' time in service after November 17, 1980. To prevent loss of directional control as a result of possible tail rotor pitch link failure, accomplish the following, unless already accomplished in accordance with Bell Helicopter Textron Alert Service Bulletin No. 47-80-5, Rev. A, dated April 29, 1980. (a) Remove the tail rotor pitch link from each blade pitch horn. (b) Inspect the pitch link bearings for axial and radial play. Remove bearings having .015 inch or more of play or looseness, and install serviceable bearings. (c) Install bolts P/N NAS1304-32D or 20-057-4-32D (used with pitch horn, P/N 47-641-187-1, -3, or -5), or P/N NAS1304-30D, or 20-057-4-30D (used with pitch horn, P/N 47-641-187-7) as appropriate, with washer, P/N 47-641-189-1 or -3 under the bolt head or nut, and washer P/N 47-641-189-3 between the link bearing and pitch horn with bevel towards the bearing. Torque nuts 80 to 100 inch-pounds and install cotter pins. (d) Determine that no binding or interference occurs in the blade controls when the tail rotor controls are full left and right, and the tail rotor hub is flapped to each stop. Track the tail rotor blades in accordance with the appropriate Model 47 maintenance manual if a rod end bearing or a link is replaced in accordance with paragraph (b) of this AD. (e) Equivalent means of compliance with this AD may be approved by the Chief, Engineering and Manufacturing Branch, Flight Standards Division, FAA, Southwest Region. (Bell Helicopter Textron Operations Safety Notice OSN 47-79-1 dated October 19, 1979, also pertains to this subject.) Amendment 39-3942 became effective November 17, 1980. This amendment 39-3976 becomes effective November 24, 1980. FOOTER:
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