- Model
- Navion (Army L-17A)
- Data sheet
- TCDSA-782
- Registered aircraft
- 373 matched by model
- Product
- Aircraft · Small airplane
Unofficial copy of the text in the FAA’s Dynamic Regulatory System. The FAA’s own copy is the authoritative one. DRS record last changed May 30, 2024.
Copies of the files this page was built from, with their SHA-256. Retrieved October 18, 2026.
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| FAA DRS HTML | 20 KB | 9d75348c…7d76da0 | FAA DRS (API key needed) |
On this page
The airworthiness directive
47-11-02 NAVION: (Was Mandatory note 2 of AD-782-3.) Applies to All Models Equipped With Hartzell HC12x20-1 Propeller Hubs and 8628 Blades.
To be accomplished not later than May 1, 1947.
Vibration tests of the Hartzell HC12x20-1 propeller with these airplanes indicate that the propeller diameter should be reduced from 86 inches to 84 inches. This is accomplished by cutting 1 inch from the tip of each 8628 blade, and making the shortened blade 18428R. This blade rework must be performed either by the Hartzell factory or by a certified propeller repair agency.
(Par. B of North American Field Service Bulletin No. 20 dated January 28, 1947, covers this rework.)
Upon compliance with this AD, the presently required placard against engine operation between 1,950 and 2,150 r.p.m. and over 2,250 r.p.m. may be removed.
Affected TCDS · 1
The type certificate data sheets for the models this AD names, matched by model and maker.
Registered aircraft · 373
Registered aircraft whose airframe or engine model this AD names. Matched by model only, so check each against the AD’s applicability.
| 1946 | 78 |
|---|---|
| 1947 | 98 |
| 1948 | 88 |
| 1949 | 23 |
| 1950 | 2 |
| 1951 | 1 |
| 1956 | 1 |
| 1958 | 1 |
| 1959 | 1 |
80 with no year recorded