AD 88-15-08

88-15-08 DE HAVILLAND: Amendment 39-5978. Applies to Model DHC-3 (all serial numbers) airplanes certificated in any category.

Compliance: Required as indicated, unless already accomplished in accordance with AD 85-11-01, Amendment 39-5071.

To prevent disengagement of the folding utility seat forward leg from the floor mounting rail, which could result in hazards to seat occupants from an inadequately restrained seat during a crash, accomplish the following:

(a) Within 50 hours time-in-service (TIS) after the effective date of this AD, and at subsequent intervals of 50 hours TIS, attempt to move the lower end of each leg sideways into the open part of the keyhole slot using as much force as can be exerted by hand. If the leg can be released from the keyhole slot, remove the seat from service until DeHavilland Modification No. 3/932 is incorporated. (This modification is contained in DeHavilland Service Bulletin No. 3/42, Revision A, dated September 18, 1987).(b) Repeat the check in Paragraph (a) of this AD each time the seats are moved from the stowed to deployed position.

(c) The check required by Paragraph (b) of this AD may be accomplished by a flightcrew member, certificated under FAR 61 or FAR 63 rules, briefed on the procedure.

NOTE: When the checks required by Paragraph (b) of this AD are accomplished by a flightcrew member pursuant to the restrictions specified in Paragraph (c) of this AD, maintenance records must be made as required by FAR 43.9 and those records must be maintained as required by FAR 91.173, 121.380, or 135.439 as applicable.

(d) When Modification No. 3/932 is installed in accordance with the "ACCOMPLISHMENT INSTRUCTIONS" of DeHavilland S/B No. 3/42, Revision A, on each seat, subsequent checks required by this AD are no longer required.

(e) An equivalent means of compliance may be used when approved by the Manager, New York Aircraft Certification Office, Federal Aviation Administration, FAA, New England Region, 181 South Franklin Avenue, Valley Stream, New York 11581.

All persons affected by this directive may obtain copies of the documents referred to herein upon request to the DeHavilland Aircraft Company of Canada, a Division of Boeing of Canada, Ltd, Garratt Boulevard, Downsview, Ontario, Canada M3K 1Y5; Telephone (416) 633- 7310, or these documents may be examined at the FAA, Office of the Regional Counsel, Room 1558, 601 East 12th Street, Kansas City, Missouri 64106.

This AD supersedes AD 85-11-01, Amendment 39-5071.

This amendment, 39-5978, becomes effective on August 27, 1988.