Shortly after landing at Perth and taxiing clear of the runway, the crew of the Metroliner observed smoke accumulating and increasing in intensity in the cockpit. The crew stopped the aircraft on the taxiway, shutdown the engines, notified air traffic services of the problem and commenced disembarkation of the aircraft. After the passengers had safely disembarked, the pilot in command re-entered the aircraft and observed that, with the engines stopped, the smoke had begun to dissipate from the cabin and cockpit.
The operator's maintenance investigation found that the right air cycle machine (ACM) had leaked oil into the airconditioning system, that had then entered the cabin as smoke and fumes. The ACM turbine had seized. The Chief Engineer reported that the company conducted a fleet wide analysis to see if a failure trend could be identified for the ACM units. They determined that the Metro fleet had used a total of ten ACM's since 1999, with six being used by the incident aircraft alone. The usage was evenly distributed between left and right installations of the units. The conclusion was that the air delivery system to the ACM's might have a partial blockage leading to the premature failures.
Local Safety Action
Due to the access difficulties with the ACM air delivery system, the Chief Engineer planned to program the entire fleet for in-depth inspections to verify/rectify the blockages as the opportunity arose. The exact start date of the program had not been determined at the time of publication of this report.
|Date:||20 August 2001||Investigation status:||Completed|
|Time:||1004 hours WST|
|State:||Western Australia||Occurrence type:||Air/pressurisation|
|Release date:||23 October 2001||Occurrence category:||Incident|
|Report status:||Final||Highest injury level:||None|
|Aircraft manufacturer||Fairchild Industries Inc|
|Type of operation||Charter|
|Damage to aircraft||Nil|
|Departure point||Jundee, WA|
|Departure time||0831 hours WST|
|Role||Class of licence||Hours on type||Hours total|