AD 75-12-09 R2
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Twin Commander Aircraft LLC | 500 | Airworthiness Directives; Rockwell Model 500, 500A, 500B, 500S, 500U, 520, 560, 560A, 560E, 560F, 680, 680E, 680F, 680F(P), and 720 Airplanes |
| aircraft | Twin Commander Aircraft LLC | 500-A | Airworthiness Directives; Rockwell Model 500, 500A, 500B, 500S, 500U, 520, 560, 560A, 560E, 560F, 680, 680E, 680F, 680F(P), and 720 Airplanes |
| aircraft | Twin Commander Aircraft LLC | 500-B | Airworthiness Directives; Rockwell Model 500, 500A, 500B, 500S, 500U, 520, 560, 560A, 560E, 560F, 680, 680E, 680F, 680F(P), and 720 Airplanes |
| aircraft | Twin Commander Aircraft LLC | 500-S | Airworthiness Directives; Rockwell Model 500, 500A, 500B, 500S, 500U, 520, 560, 560A, 560E, 560F, 680, 680E, 680F, 680F(P), and 720 Airplanes |
| aircraft | Twin Commander Aircraft LLC | 500-U | Airworthiness Directives; Rockwell Model 500, 500A, 500B, 500S, 500U, 520, 560, 560A, 560E, 560F, 680, 680E, 680F, 680F(P), and 720 Airplanes |
| aircraft | Twin Commander Aircraft LLC | 520 | Airworthiness Directives; Rockwell Model 500, 500A, 500B, 500S, 500U, 520, 560, 560A, 560E, 560F, 680, 680E, 680F, 680F(P), and 720 Airplanes |
| aircraft | Twin Commander Aircraft LLC | 560 | Airworthiness Directives; Rockwell Model 500, 500A, 500B, 500S, 500U, 520, 560, 560A, 560E, 560F, 680, 680E, 680F, 680F(P), and 720 Airplanes |
| aircraft | Twin Commander Aircraft LLC | 560-A | Airworthiness Directives; Rockwell Model 500, 500A, 500B, 500S, 500U, 520, 560, 560A, 560E, 560F, 680, 680E, 680F, 680F(P), and 720 Airplanes |
| aircraft | Twin Commander Aircraft LLC | 560-E | Airworthiness Directives; Rockwell Model 500, 500A, 500B, 500S, 500U, 520, 560, 560A, 560E, 560F, 680, 680E, 680F, 680F(P), and 720 Airplanes |
| aircraft | Twin Commander Aircraft LLC | 560-F | Airworthiness Directives; Rockwell Model 500, 500A, 500B, 500S, 500U, 520, 560, 560A, 560E, 560F, 680, 680E, 680F, 680F(P), and 720 Airplanes |
| aircraft | Twin Commander Aircraft LLC | 680 | Airworthiness Directives; Rockwell Model 500, 500A, 500B, 500S, 500U, 520, 560, 560A, 560E, 560F, 680, 680E, 680F, 680F(P), and 720 Airplanes |
| aircraft | Twin Commander Aircraft LLC | 680-E | Airworthiness Directives; Rockwell Model 500, 500A, 500B, 500S, 500U, 520, 560, 560A, 560E, 560F, 680, 680E, 680F, 680F(P), and 720 Airplanes |
| aircraft | Twin Commander Aircraft LLC | 680-F | Airworthiness Directives; Rockwell Model 500, 500A, 500B, 500S, 500U, 520, 560, 560A, 560E, 560F, 680, 680E, 680F, 680F(P), and 720 Airplanes |
| aircraft | Twin Commander Aircraft LLC | 680-F(P) | Airworthiness Directives; Rockwell Model 500, 500A, 500B, 500S, 500U, 520, 560, 560A, 560E, 560F, 680, 680E, 680F, 680F(P), and 720 Airplanes |
| aircraft | Twin Commander Aircraft LLC | 720 | Airworthiness Directives; Rockwell Model 500, 500A, 500B, 500S, 500U, 520, 560, 560A, 560E, 560F, 680, 680E, 680F, 680F(P), and 720 Airplanes |
Unsafe Condition
Inadvertent pilot induced structural failure
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Install 'bob weights' in accordance with specified service bulletins or equivalent procedures approved by the FAA. Aircraft previously complying with earlier service bulletins must also comply with Service Bulletin No. 152 or 179 as applicable, including inspections and repairs per the bulletins.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Within 300 hours' time in service after the effective date of this AD (November 28, 1981) for initial installations. Subsequent inspections for some aircraft must be completed within 25 hours' time in service after specific dates (e.g., August 9, 1981 for certain models).
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
Rockwell Models 500, 500A, 500B, 500S, 500U, 520, 560, 560A, 560E, 560F, 680, 680E, 680F, 680F(P), and 720 through Serial Number 3323, certificated in all categories.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Inadvertent Structural Failure
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_75-12-09_R.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 75-12-09 R2 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Rockwell Model 500, 500A, 500B, 500S, 500U, 520, 560, 560A, 560E, 560F, 6...Show more Subject: Inadvertent Structural Failure Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 11/28/1981 Make: Twin Commander Aircraft LLC Model: 500 | 500-A | 500-B | 500-S | 500-U | 520 | 560 | 560-A | 560-E | 560-F | 680 | 680-E | 680-F | 680-...Show more Product Type: Aircraft Product Subtype: Small Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 75-12-09 R2 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-4246 AD NUMBER: 75-12-09 R2 SUBJECT HEADING: Airworthiness Directives; Rockwell Model 500, 500A, 500B, 500S, 500U, 520, 560, 560A, 560E, 560F, 680, 680E, 680F, 680F(P), and 720 Airplanes ACTION: SUMMARY: DATES: Effective November 28, 1981. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 75-12-09 R2 ROCKWELL: Amendment 39-2223 as amended by Amendment 39-4166 is further amended by Amendment 39-4246. Applies to Models 500, 500A, 500B, 500S, 500U, 520, 560, 560A, 560E, 560F, 680, 680E, 680F, 680F(P), and 720, through Serial Number 3323 airplanes certificated in all categories. Compliance is required as indicated. Within the next 300 hours' time in service after the effective date of this AD, to prevent inadvertent pilot induced structural failure, install "bob weights" in accordance with Rockwell International Service Bulletin No. 128, Revision 1, dated April 24, 1975, or No. 129, Revision 2, dated May 9, 1975, or No. 136, Revision 1, dated May 9, 1975 (or later FAA approved revision), or an equivalent procedure approved by the Chief, Engineering and Manufacturing Branch, Southwest Region, Federal Aviation Administration, Fort Worth, Texas, unless already accomplished in accordance with the above revised service bulletins. Aircraft that have complied with Service Bulletin No. 129 prior to Revision 2 or Service Bulletin No. 136 prior to Revision 1, must comply with Rockwell Service Bulletin No. 152 dated May 9, 1975, or an equivalent approved by the Chief, Engineering and Manufacturing Branch, Southwest Region, Federal Aviation Administration, Fort Worth, Texas, unless already accomplished. Compliance with Service Bulletin No. 152 is required within 300 hours' time in service after the effective date of this AD. Aircraft that have complied with the bob-weight installation in accordance with Service Bulletin No. 129, prior to Revision 4 dated January 26, 1981, or Service Bulletin No. 136 prior to Revision 3 dated January 26, 1981, must comply with Service Bulletin No. 179 dated January 26, 1981, or an equivalent approved by the Chief, Engineering and Manufacturing Branch, Southwest Region, Federal Aviation Administration, Fort Worth, Texas, unless already accomplished. Compliance with the inspection specified in Service Bulletin No. 179 is required as follows: a. Models 500, 500A, 500B, 500U, 520, 560, 560A, 560E, 560F, 680, 680E, 680F, 680F(P), 720, and 500S, through Serial Number 3246 aircraft certificated in all categories which have had the provisions of Service Bulletin No. 129 prior to Revision 4 dated January 26, 1981, or Service Bulletin No. 136 prior to Revision 3 dated January 26, 1981, and Service Bulletin No. 152 dated May 9, 1975, which required the bob-weight installation or an equivalent approved by the Chief, Engineering and Manufacturing Branch, Southwest Region, Federal Aviation Administration, Fort Worth, Texas, accomplished; within 25 hours' time in service after August 9, 1981. When compliance with the repair or strengthening of the supports in accordance with Service Bulletin No. 129, Revision 4, or Service Bulletin No. 136, Revision 3, has been accomplished, the repetitive 25-hour inspection of Service Bulletin No. 179 may be discontinued. b. Model 500S, Serial Numbers 3247 through 3323, aircraft certificated in all categories; within 25 hours' time in service after the effective inspection of Service Bulletin No. 179. This repetitive 25-hour inspection may be discontinued when the repair or strengthening of the supports is accomplished in accordance with Part II of Service Bulletin No. 179. In accordance with FAR 21.197, a ferry flight is permitted to a base where the inspection, repair or modification required by this AD may be accomplished. Copies of these bulletins may be obtained by contacting the Service Manager, Gulfstream American Corporation, 5001 North Rockwell Avenue, Bethany, Oklahoma 73008. Amendment 39-2223 became effective July 2, 1975. Amendment 39-4166 became effective August 9, 1981. This amendment 39-4246 becomes effective November 28, 1981. FOOTER:
Document Text
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AD Final Rules - DRS_75-12-09_R.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 75-12-09 R2 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Rockwell Model 500, 500A, 500B, 500S, 500U, 520, 560, 560A, 560E, 560F, 6...Show more Subject: Inadvertent Structural Failure Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 11/28/1981 Make: Twin Commander Aircraft LLC Model: 500 | 500-A | 500-B | 500-S | 500-U | 520 | 560 | 560-A | 560-E | 560-F | 680 | 680-E | 680-F | 680-...Show more Product Type: Aircraft Product Subtype: Small Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 75-12-09 R2 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-4246 AD NUMBER: 75-12-09 R2 SUBJECT HEADING: Airworthiness Directives; Rockwell Model 500, 500A, 500B, 500S, 500U, 520, 560, 560A, 560E, 560F, 680, 680E, 680F, 680F(P), and 720 Airplanes ACTION: SUMMARY: DATES: Effective November 28, 1981. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 75-12-09 R2 ROCKWELL: Amendment 39-2223 as amended by Amendment 39-4166 is further amended by Amendment 39-4246. Applies to Models 500, 500A, 500B, 500S, 500U, 520, 560, 560A, 560E, 560F, 680, 680E, 680F, 680F(P), and 720, through Serial Number 3323 airplanes certificated in all categories. Compliance is required as indicated. Within the next 300 hours' time in service after the effective date of this AD, to prevent inadvertent pilot induced structural failure, install "bob weights" in accordance with Rockwell International Service Bulletin No. 128, Revision 1, dated April 24, 1975, or No. 129, Revision 2, dated May 9, 1975, or No. 136, Revision 1, dated May 9, 1975 (or later FAA approved revision), or an equivalent procedure approved by the Chief, Engineering and Manufacturing Branch, Southwest Region, Federal Aviation Administration, Fort Worth, Texas, unless already accomplished in accordance with the above revised service bulletins. Aircraft that have complied with Service Bulletin No. 129 prior to Revision 2 or Service Bulletin No. 136 prior to Revision 1, must comply with Rockwell Service Bulletin No. 152 dated May 9, 1975, or an equivalent approved by the Chief, Engineering and Manufacturing Branch, Southwest Region, Federal Aviation Administration, Fort Worth, Texas, unless already accomplished. Compliance with Service Bulletin No. 152 is required within 300 hours' time in service after the effective date of this AD. Aircraft that have complied with the bob-weight installation in accordance with Service Bulletin No. 129, prior to Revision 4 dated January 26, 1981, or Service Bulletin No. 136 prior to Revision 3 dated January 26, 1981, must comply with Service Bulletin No. 179 dated January 26, 1981, or an equivalent approved by the Chief, Engineering and Manufacturing Branch, Southwest Region, Federal Aviation Administration, Fort Worth, Texas, unless already accomplished. Compliance with the inspection specified in Service Bulletin No. 179 is required as follows: a. Models 500, 500A, 500B, 500U, 520, 560, 560A, 560E, 560F, 680, 680E, 680F, 680F(P), 720, and 500S, through Serial Number 3246 aircraft certificated in all categories which have had the provisions of Service Bulletin No. 129 prior to Revision 4 dated January 26, 1981, or Service Bulletin No. 136 prior to Revision 3 dated January 26, 1981, and Service Bulletin No. 152 dated May 9, 1975, which required the bob-weight installation or an equivalent approved by the Chief, Engineering and Manufacturing Branch, Southwest Region, Federal Aviation Administration, Fort Worth, Texas, accomplished; within 25 hours' time in service after August 9, 1981. When compliance with the repair or strengthening of the supports in accordance with Service Bulletin No. 129, Revision 4, or Service Bulletin No. 136, Revision 3, has been accomplished, the repetitive 25-hour inspection of Service Bulletin No. 179 may be discontinued. b. Model 500S, Serial Numbers 3247 through 3323, aircraft certificated in all categories; within 25 hours' time in service after the effective inspection of Service Bulletin No. 179. This repetitive 25-hour inspection may be discontinued when the repair or strengthening of the supports is accomplished in accordance with Part II of Service Bulletin No. 179. In accordance with FAR 21.197, a ferry flight is permitted to a base where the inspection, repair or modification required by this AD may be accomplished. Copies of these bulletins may be obtained by contacting the Service Manager, Gulfstream American Corporation, 5001 North Rockwell Avenue, Bethany, Oklahoma 73008. Amendment 39-2223 became effective July 2, 1975. Amendment 39-4166 became effective August 9, 1981. This amendment 39-4246 becomes effective November 28, 1981. FOOTER:
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Retrieved: Apr 8, 2026
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