AD/AL 250/70 No. 8 Bearing Scavenge Line Air/Oil Separator Cancelled (Cth)

AIRWORTHINESS DIRECTIVE

On the effective date specified below, and for the reasons set out in the background section, the CASA delegate whose signature appears below revokes Airworthiness Directive AD/AL 250/70.

Allison Turbine Engines - 250 Series

AD/AL 250/70 No. 8 Bearing Scavenge Line Air/Oil Separator 6/2009

Requirement:

CANCELLED.

This AD is cancelled on 4 June 2009.

Background:

This unique Australian AD raised in 1986 against Allison Commercial Engine Bulletin (CEB) 250 CEB-A-72-1238 required a modification by installation of an air/oil separator in the No.8 bearing scavenge line to improve venting of bearing oil sump due to possibility of excess pressure causing internal oil fire and subsequent No.1 turbine wheel failure.

Compliance was:  Within 100 hours of engine operation after 31 August 1986 but no later than 31 January 1987.

This AD has been sufficiently promulgated for the affected engine to have been modified by now; therefore this AD is considered to be no longer required.

James Coyne
Delegate of the Civil Aviation Safety Authority

24 April 2009