AD 60-20-02 ACTIVE

60-20-02 HAMILTON STANDARD: Amdt. 201 Part 507 Federal Register September 23, 1960. Applies to All 34E60 Propellers.

Compliance required as indicated.

As a result of two recent dome cap fractures one resulting in propeller overspeed and inability to feather the following must be accomplished:

(a) All dome caps must be examined in the threaded area for crack indications in the inside diameter and outside diameter by means of visual or dye penetrant or magnetic particle inspection within the next 50 hours' time in service unless already accomplished within the last 50 hours.

(b) Dome caps inspected visually only must be reexamined by means of dye penetrant or magnetic particle inspection within the next 200 hours' time in service.

(c) Caps with indications of cracks must be replaced with caps which have also been inspected in accordance with the foregoing inspection provisions and found to have no crack indications.

(d) Upon reinstallation caps mustbe tightened to 350-450 foot-pounds.

(e) Dome caps must be reexamined by means of dye penetrant or magnetic particle inspection within the next 350 hours' time in service after the last dye penetrant or magnetic particle inspection made in accordance with paragraphs (a) or (b). This inspection must be repeated at intervals not to exceed 350 hours' time in service until new design-strengthened dome caps, P/N 565334, have been installed. (Hamilton Standard telegram to all operators dated September 16, 1960, covers this same subject.)

NOTE: The replaced caps should be returned to Hamilton Standard.

(Hamilton Standard telegram dated August 29, 1960, covers this subject.)

This airworthiness directive sent by telegram to all known operators of Douglas DC-7 Series and Boeing B-377 aircraft equipped with Hamilton Standard 34E60 propellers on September 2, 1960. Effective on date of publication in the Federal Register to all persons not receiving telegram of September 2, 1960.

Revised October 15, 1960.