Aviation safety investigations & reports

Boeing Co 737-33A, VH-CZW

Investigation number:
200003034
Status: Completed
Investigation completed

Summary

During completion of routine fuel sampling, before the first flight of the day, maintenance personnel reported finding a red/ brown liquid present in the fuel sample removed from the Boeing 737 aircraft. An inspection of the aircraft's fuel system was carried out with no blockage of filters or other safety of flight issues related to the contamination found.

Testing of the fuel recovered indicated no fungal (cladisporium resinae) species. However, there was a heavy load of bacteria (pseudomonas) present in the water layer, with a related film between the water and fuel layers. The contamination was not believed to be aircraft created but fuel source related. Operators held meetings with fuel company representatives, CASA, and the ATSB attempting to determine the origin of the contamination. Fuel company representatives contacted their refineries but none reported abnormal water drains. Mapping of the fuel supplied to the aircraft reported as contaminated was completed by the operator with no common fuel upload origin point defined.

Research identified several past similar events in Australia. One such event in 1962 was experienced on Boeing 707 aircraft and was believed related to sulphonates in the fuel combining with trace levels of transition metals (including iron). Similar events, reported in 1996 and 1997, were believed to have been caused by the reaction of a complex of naphthenic/ sulphonic acids with transition metals (including iron).

Despite intensive investigation of this event, the source of the contamination could not be established and sporadic reports of contaminated fuel samples persist. This contamination was not related to the aviation gasoline (AVGAS) contamination reported in December 1999, as analysis confirmed no presence of Ethylene Diamine.

General details
Date: 21 July 2000   Investigation status: Completed  
Time: 0500 hours CST    
Location   (show map): Adelaide, Aero.    
State: South Australia   Occurrence type: Fuel contamination  
Release date: 22 January 2001   Occurrence category: Incident  
Report status: Final   Highest injury level: None  

Aircraft 1 details

Aircraft 1 details
Aircraft manufacturer The Boeing Company  
Aircraft model 737  
Aircraft registration VH-CZW  
Serial number 23832  
Type of operation Air Transport High Capacity  
Damage to aircraft Nil  
Departure point Adelaide, SA  
Destination Melbourne, VIC  

Aircraft 2 details

Aircraft 2 details
Aircraft manufacturer The Boeing Company  
Aircraft model 737  
Aircraft registration VH-CZW  
Serial number 23832  
Type of operation Air Transport High Capacity  
Damage to aircraft Nil  
Departure point Adelaide, SA  
Destination Melbourne, VIC  
Last update 13 May 2014