AD 47-21-05
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Sierra Hotel Aero, Inc. | Navion (Army L-17A) | Airworthiness Directives; Navion Serial Numbers NAV-4-11 Through 21 and 44 Through 47 |
Unsafe Condition
The original propeller control lacks a positive friction lock, which could result in unintended movement of the propeller control lever during flight.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Replace the original propeller control with one incorporating a positive friction lock as per NAA Kit Drawing 145-89011. Refer to NAA Field Service Bulletin No. 5 for guidance.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
not later than August 1, 1947
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Affected Aircraft
Sierra Hotel Aero, Inc. Navion (Army L-17A) serial numbers NAV-4-11 through 21 and 44 through 47
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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