AD/AL 250/89 - Gas Producer Rotor Tie Bolt (Cth)

AIRWORTHINESS DIRECTIVE For the reasons set out in the background section, the CASA delegate whose signature appears below issues the following Airworthiness Directive (AD) under subregulation 39.001(1) of CASR 1998. The AD requires that the action set out in the requirement section (being action that the delegate considers necessary to correct the unsafe condition) be taken in relation to the aircraft or aeronautical product mentioned in the applicability section: (a) in the circumstances mentioned in the requirement section; and (b) in accordance with the instructions set out in the requirement section; and (c) at the time mentioned in the compliance section.

Allison Turbine Engines - 250 Series AD/AL 250/89 Gas Producer Rotor Tie Bolt 9/2006

Applicability: Rolls-Royce Corporation (formerly Allison Engine Company, Allison Gas Turbine Division, and Detroit Diesel Allison) 250-B17, -B17B, -B17C, -B17D, -B17E, -B17F, -B17F/1, -B17F/ 2, 250-C18, -C20, -C20B, -C20F, -C20J, -C20R, -C20R/1, -C20R/2, -C20R/4, -C20S, and C20W series turboprop and turboshaft engines with the gas producer rotor assembly tie bolt part numbers (P/Ns) listed in Table 1 of this Airworthiness Directive installed.

Table 1. - Affected Gas Producer Rotor Assembly Tie Bolts Manufacturer Affected part numbers (P/N) EXTEX Ltd. (EXTEX) A23008020 and E23008020 Rolls-Royce Corporation (RRC) 23008020, 6843388 and 6876991 Superior Air Parts Inc. (SAP) A23008020 Pacific Sky Supply Inc 23008020P

Note 1: These engines are installed on, but not limited to, aircraft listed in Table 2 of this AD:

Table 2. - Applicable Aircraft Helicopter Models Agusta A109, A109A, A109A II, A109C. Arrow Falcon Exporters OH-58A+ and OH-58C. Bell Textron 206A, 206B, 206L. Enstrom TH-28, 480, 480B. Eurocopter France AS355E, AS355F, AS355F1, AS355F2.