Document ID: chunk:federal_register_of_legislation:F2006B02291:body:0:p1
Version: federal_register_of_legislation:F2006B02291
Segment Type: other
Provision Reference: 
Character Range: 20–3893

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 39.1 (1) of CAR 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 250/81 Third Stage Turbine Wheels 6/2002

            Applicability:  Allison 250 - C28 Engines with third stage turbine wheels Part Number (P/N) 6899383 and with Serial Numbers (S/N) listed in Table 1 of this Directive.

            Requirement: Remove from service all turbine wheels P/N 6899383 listed by S/N in Table 1 of this Directive.

            Note: FAA AD 2002-06-08 refers.

 Compliance: Effective 13 June 2002; as per Table 2 of this Directive.

            This Airworthiness Directive becomes effective on 13 June 2002.

            Background: Fractures of the third stage turbine blade tips and shrouds could cause uncommanded shutdowns. New lower life limits have been established to address this problem.
            This Directive requires the removal from service of certain turbine wheels that exceed the new lower life limits.

                    Table 1. S/N's of Affected Third Stage Turbine Wheels

HX91428R       HX91489R       HX91707R
HX91456R       HX91490R       HX91708R
HX91457R       HX91492R       HX91709R
HX91428R       HX91489R       HX91707R
HX91456R       HX91490R       HX91708R
HX91457R       HX91492R       HX91709R
HX91458R       HX91493R       HX91710R
HX91459R       HX91494R       HX91711R

     HX91461R   HX91500R       HX91712R
     HX91462R   HX91501R       HX91713R
     HX91464R   HX91503R       HX91714R
      HX914659  HX91504R       HX91715R
     HX91465R   HX91506R       HX91721R
     HX91466R   HX91507R       HX91722R
     HX91467R   HX91508R       HX91726R
     HX91468R   HX91510R       HX91733R
     HX91469R   HX91511R       HX91735R
     HX91471R   HX91512R       HX91736R
     HX91472R   HX91513R       HX91738R
     HX91473R   HX91519R       HX91742R
     HX91474R   HX91520R       HX91744R
     HX91475R   HX91522R       HX91748R
     HX91477R   HX91523R       HX91749R
     HX91478R   HX91524R       HX91750R
     HX91480R   HX91525R       HX91754R
     HX91482R   HX91526R       HX91764R
     HX91483R   HX91527R       HX91765R
     HX91485R   HX91528R       HX91766R
     HX91486R   HX91529R       HX91767R
     HX91487R   HX91530R       HX91768R
     HX91488R   HX91706R       HX91769R

                             Table 2. Removal Schedule

   As of the effective date of this AD                                                                           Remove by
 (1) With fewer than 2,800 cycles-since- new (CSN), and fewer than 1,400 hours' time-since-new (TSN).   3,000 CSN or 1,500 hours TSN,
                                                                                                        whichever occurs earlier.
 (2) With between 2,800 and 3,000 CSN (inclusive), and fewer than 1,500 hours TSN.                      200 additional cycles or 100 additional hours, after the effective date of this AD, whichever occurs earlier.
 (3) With fewer than 3,000 CSN, and between 1,500 and 3,000 hours TSN.                                  100 additional hours, after the effective date of this AD.
 (4) With between 3,000 and 6,000 CSN (inclusive), and fewer than 1,500 hours TSN.                      200 additional cycles, after the effective date of this AD.
 (5) With