Airworthiness Directive · Amendment 39-11650 · Turbomeca Arrius 1A Series Turboshaft Engines
Turbomeca Arrius 1A Series Turboshaft Engines
Turbomeca Arrius 1A series turboshaft engines, installed on but not limited to Ecureuil AD355 series helicopters.
Note 1: This airworthiness directive (AD) applies to each engine identified in the preceding applicability provision, regardless of whether it has been modified, altered, or repaired in the area subject to the requirements of this AD. For engines that have been modified, altered, or repaired so that the performance of the requirements of this AD is affected, the owner/operator must request approval for an alternative method of compliance in accordance with paragraph (c) of this AD. The request should include an assessment of the effect of the modification, alteration, or repair on the unsafe condition addressed by this AD; and, if the unsafe condition has not been eliminated, the request should include specific proposed actions to address it.
This amendment adopts a new airworthiness directive (AD), applicable to Turbomeca Arrius 1A series turboshaft engines, that requires installation of module TU63, which provides a separate supply of fuel for one of the 10 main injectors of the fuel injection system. This action is prompted by reports of unexpected power loss during test flights. The actions specified by this AD are intended to prevent unexpected power loss, which could result in an uncommanded in-flight engine shutdown, autorotation, and forced landing.
(a) Install module TU63 in accordance with the Instructions for Incorporation of Turbomeca Arrius Service Bulletin (SB) No. 319 73 0016, Revision 1, dated December 22, 1997, at the earliest of the following after the effective date of this AD:
(1). The next shop visit, or
(2). Within 120 cycles-in-service, or
(3). Within 30 days.
(b) For the purpose of this AD, a shop visit is defined as whenever the engine is removed from the helicopter for maintenance.
The aircraft, engines and makers this AD names, by the model designations in its text. A model listed here may still be outside the AD's serial ranges.
Engines
