AD 75-12-09 R2

final rule
Data completeness: 70%

Airworthiness Directives; Rockwell Model 500, 500A, 500B, 500S, 500U, 520, 560, 560A, 560E, 560F, 680, 680E, 680F, 680F(P), and 720 Airplanes

AD Number
75-12-09 R2
Status
final_rule
Effective Date
Product Category
aircraft
Docket
Unknown
FR Citation
This information is not available.

Applicability

TypeManufacturerModelDetails
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

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.

Source: Official FAA Source ↗

Retrieved: Apr 8, 2026

Rights: U.S. Government Public Domain

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