Ad/Cessna 500/22 - Brake Shuttle Valve - 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/CESSNA 500/22.

Cessna 500 (Citation) Series Aeroplanes

AD/CESSNA 500/22 Brake Shuttle Valve 10/2008

Requirement:

CANCELLED.

This AD is cancelled on 25 September 2008.

Background:

This unique Australian AD, raised in 1990 against Cessna Citation Alert Service Letter (SL) No. SLA 500-32-46 and BF Goodrich Service Bulletin (SB) No. 517, required an inspection and modification after reports of leaking brake shuttle valves attributed to slow deterioration of shuttle valve o-ring material as a result of exposure to incompatible seal lubricant.

Compliance was:  inspect within 50 hours TIS after 17 May 1990 and thereafter at intervals not to exceed 50 TIS until modified.  Modification required within 200 hours TIS after 17 May 1990.

As all affected aircraft would have been inspected and modified by now, this AD is considered to be no longer required.

James Coyne
Delegate of the Civil Aviation Safety Authority

7 August 2008