AD 91-03-05 ACTIVE

91-03-05 AIRSHIP INDUSTRIES: Amendment No. 39-6871; Docket No. 90-CE-50-AD.

Applicability: Skyship Model 600 airships (all serial numbers), certificated in any category.

Compliance: Required within the next 250 hours time-in-service after the effective date of this AD, unless already accomplished.

To prevent ignition control unit failure and subsequent total loss of engine power, accomplish the following:

(a) Remove all ignition control units, Part Number (P/N) ASI/L/80 Issue D, MOD 1 or 2, and replace with P/N ASI/L/80 Issue E, MOD 3 ignition control units, as described in Airship Industries Service Bulletin (SB) REF 600-74-314, Revision 1, dated June 5, 1990.

(b) Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate airplanes to a base in order to comply with the requirements of this AD.

(c) An alternate method of compliance or adjustment of the compliance time that provides an equivalent level of safety may be approved by the Manager, Aircraft Certification Staff, Europe, Africa and Middle East Office, FAA, c/o American Embassy, B-1000 Brussels, Belgium. The request should be forwarded through an appropriate FAA Maintenance Inspector, who may add comments and then send it to the Manager, Brussels Aircraft Certification Staff.

(d) All persons affected by this directive may obtain copies of the document referred to herein upon request to Airship Industries Limited, Manager, Technical Publications, Shortstown, Bedford, MK42 OTF, England; or Airship Industries USA, Inc., Engineering Manager, Route 4, Box 109, Elizabeth City, North Carolina 27909; or may examine this document at the FAA, Central Region, Office of the Assistant Chief Counsel, Room 1558, 601 E. 12th Street, Kansas City, Missouri 64106.

This amendment (39-6871, AD 91-03-05) becomes effective on February 28, 1991.