AD 59-06-04

Airworthiness directive · Hydraulic Actuating Cylinders · Sierra Hotel Aero Navion (Army L-17A), Navion A (Army L-17B and L-17C), Navion B and 1 more

Models
Navion (Army L-17A), Navion A (Army L-17B and L-17C), Navion B, Navion D
Data sheet
TCDSA-782
Registered aircraft
754 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.

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The airworthiness directive

59-06-04 NAVION: Tusco Corporation (Navion) Applies to All Models.

Several failures of hydraulic actuating cylinders have occurred causing the loss of the use of the flaps and the landing gear to collapse.

To prevent further difficulties of this nature, the following items must be accomplished by May 1, 1959, and at each periodic inspection thereafter.

(1) Inspect the flap and landing gear actuating cylinders for cracks. If any cracks appear, the cylinder must be replaced.

(2) Determine, by means of a hydraulic gage, that the hydraulic system pressure relief valve is adjusted to 1125+25, -0 p.s.i. Excessive pressures could cause damage to the components of the system.

(3) Hydraulic fluid restrictors are required in the nose gear lines, Serial Numbers 1271 and subsequent, main gear lines, Serial Numbers 1790 and subsequent, and flap lines, all serial numbers.

(4) Inspect the linkage adjustments of the landing gear bungee springs and the flap stops anddetermine that they have been properly adjusted in accordance with appropriate service manuals.

(Tusco Corporation Service Letter No. 79 dated December 23, 1958, covers this same subject.)

Affected TCDS · 1

The type certificate data sheets for the models this AD names, matched by model and maker.

Registered aircraft · 754

Registered aircraft whose airframe or engine model this AD names. Matched by model only, so check each against the AD’s applicability.

By aircraft maker
  • Ryan355 aircraft
  • North American253 aircraft
  • Navion146 aircraft
By year built
19461963
Registered aircraft by year built: 571 aircraft
1946105
1947135
1948144
194978
195070
195132
19521
19531
19561
19582
19591
19631

183 with no year recorded

By model

Aircraft

See all 754 aircraft