63-16-06 UNIVERSAL: Amdt. 590 Part 507 Federal Register
service after the effective date of this AD, and at each periodic inspection thereafter.
The landing gear selector valve end fitting P/N 145-58145-3 (heat- treated and nonheat-treated) has a service history of failure during attempts to extend the gear. To preclude further difficulties:
Inspect the gear actuating system in accordance with Navion Service Letter No. 81 dated March 31, 1961. Any defective parts found as a result of this inspection must be replaced before further flight.
This directive effective August 23, 1963.