77-14-17 R1: Fuel and Oil Hose

77-14-17 R1 DORNIER GmbH: Amendment 39-2966 as amended by Amendment 39-4934. Applies to all Model Do 27 and Do 28 series (all serial numbers) airplanes certificated in any category. Compliance: Required as indicated, unless already accomplished. To detect defective DORNIER fuel and oil hoses manufactured to specification LN9226 and to prevent possible engine failure or sudden seizure of an engine, accomplish the following: (a) Within the next 10 hours time-in-service (TIS) after the effective date of this Airworthiness Directive (AD), or within the next 25 hours TIS since the last inspection in accordance with AD 77-14-17, whichever occurs first, and every 25 hours thereafter until attaining more than 50 hours TIS on each hose, visually inspect each of the DORNIER fuel and oil hoses, manufactured to specification LN9226 in the first quarter of 1970 and thereafter, for defects in accordance with paragraph 1 of DORNIER Service Bulletin No. 1059-0000, dated September 25, 1975, or an FAA equivalent method. If the specification of a particular hose or its date of manufacture is unknown, the inspections required by this paragraph must be accomplished for that hose. (b) If a defective hose is found during any inspection required by paragraph (a) of this AD, before further flight, replace the defective hose with a serviceable DORNIER or TSO-C53a, Type C hose. (c) The repetitive inspections required on each individual fuel and oil hose by paragraph (a) are not required: (1) On any installed serviceable TSO-C53a, Type C hose, or (2) On any DORNIER hose which is found serviceable after the second sequential 25 hour TIS inspection, or (3) On any DORNIER hose which has more than 50 hours TIS and remains serviceable in accordance with the inspection required by paragraph (a) of this AD. (d) Airplanes may be flown in accordance with FAR 21.197 to a location where this AD may be accomplished. (e) Equivalent means of compliance may be used, if approved, by the Manager, Aircraft Certification Staff, AEU-100, Europe, Africa, and Middle East Office, FAA, c/o American Embassy, 1000 Brussels, Belgium. Amendment 39-2966 became effective on July 28, 1977. This Amendment 39-4934 becomes effective on March 22, 1985.