AD 83-16-51

83-16-51 BOEING VERTOL COMPANY: Amendment 39-4741. Applies to Boeing Vertol Model 234 series helicopters certificated in all categories.

Compliance is required as indicated (unless already accomplished).

To prevent possible hazards in flight associated with damage or loss of main rotor blade tip cap and weights, accomplish the following:

(a) Prior to further flight on helicopters equipped with main rotor blades with less than 100 hours time in service, conduct a borescope inspection of the inside root end of the spar for excessive potting material. It will be necessary to remove the tip cap to conduct this inspection. Remove any cracked potting material or any potting material in excess of one cubic inch. Remove any excess potting material in accordance with Boeing Vertol Service Bulletin No. 234621004 dated July 27, 1983, or FAA approved equivalent. less than 500 hours time in service, conduct the inspection and removal of material as stated in paragraph (a) within the next 30 hours time in service.

(c) For main rotor blades with 500 or more hours time in service conduct the inspection and removal of material as stated in paragraph (a) within the next 75 hours time in service.

(d) An equivalent method of compliance with this AD may be used when approved by the Manager, New York Aircraft Certification Office, 181 South Franklin Avenue, Valley Stream, New York 11581.

This amendment becomes effective October 26, 1983, as to all persons except those persons to whom it was made immediately effective by telegraphic AD No. T83-16-51 issued August 4, 1983, which contained the amendment.