AD 58-11-02

58-11-02 LOCKHEED: Applies to All Model 18 Aircraft.

Compliance required as indicated.

A number of reports has been received relative to cracks in the welds of the drag strut yoke (P/N XY450-2L-1) on the main landing gear. These cracks, as they progress, result in continuing reduction in the strength of the landing gear and hence render the landing gear unairworthy. It is, therefore, necessary to inspect the main landing gear for cracks in the area indicated as follows:

1. Not later than July 1, 1958, and at each 500 hours of operation thereafter inspect the main landing gear by means of dye penetrant, magnetic particle or equivalent.

2. At each 100 hours of operation conduct a visual inspection using an 8-power magnifying glass or equivalent.

In the event cracks are found, the oleo strut must be replaced.

If the oleo strut is replaced by a new part the above inspections need not be resumed until after 3,000 hours of service.

For the purpose of compliancewith this airworthiness directive, X-ray inspection is not considered an equivalent of dye penetrant or magnetic particle inspection.

This supersedes AD 58-07-02.