Occurrence Briefs are concise reports that detail the facts surrounding a transport safety occurrence, as received in the initial notification and any follow-up enquiries. They provide an opportunity to share safety messages in the absence of an investigation. Because occurrence briefs are not investigations under the Transport Safety Investigation Act 2003, the information in them is de-identified. |
What happened
On 8 March 2024, at about 1304 local time, the pilot of a Beech Super King Air 200 departed King Island Airport, Tasmania, on a private ferry return flight to Moorabbin Airport, Victoria. The pilot was the only person on board.
Passing FL160[1] on climb, the left fuel pressure and left oil pressure warning lights illuminated, and the left engine stopped shortly after. The pilot levelled off and conducted initial actions for an engine failure, secured the left engine and advised air traffic control of the engine failure. Due to the unknown fuel state onboard, the pilot conducted a return to King Island.
On descent, the pilot began to troubleshoot and identified that the engine failure was due to fuel starvation and cross-fed fuel from the right fuel system to the left engine nacelle tank, and successfully restarted the left engine. The pilot reported only using low power settings for the left engine due to concern that there would be insufficient fuel for a go-around if a higher power setting was used. The pilot conducted a normal visual approach and landing at King Island. Upon landing, the pilot checked the fuel quantity and confirmed the fuel reserves were intact.
Fuelling history
The pilot received a late roster change the previous evening which prevented them from ordering fuel for the next day. This resulted in the pilot using a company bowser in the morning which did not contain enough fuel for the planned flying that day. The pilot planned to use the remaining 700 litres of fuel in the bowser to add 350 litres to each wing. However, due to a higher than expected fill rate from the bowser, 450 litres was inadvertently added to the right fuel tanks leaving only 250 litres to add to the left fuel tanks. This resulted in a difference of 200 litres between the left and right tanks, which was within the permitted fuel discrepancy published in the pilot operating handbook. When refuelling later in the day, the pilot added 150 litres of fuel per side, however, did not correct the fuel imbalance of 200 litres.
During the flight from Moorabbin to King Island prior to the occurrence flight, the pilot detected an issue with the left fuel gauge which displayed erroneous figures. An MEL[2] was applied for the unserviceable gauge with the use of right fuel gauge only for the return sector to Moorabbin. The pilot made the decision to rely on mirroring the right fuel gauge for flight planning and inflight fuel calculations, omitting the 200 litre fuel difference.
Beech Super King Air 200 fuel system
The Super King Air 200 fuel system comprises two separate systems (one in each wing) connected by a valve-controlled cross-feed line. Within each fuel system, fuel is automatically transferred from the main and auxiliary tanks into a collector nacelle tank located directly behind the engine. In the event that one of the fuel systems is empty, fuel can be cross-fed directly to the engine from the nacelle tank in the opposite wing’s fuel system.
Safety message
Fuel starvation occurs when the fuel supply to the engine(s) is interrupted although there is usable fuel on board.
This incident reinforces the need to:
- verify pre-flight fuel quantity to determine usable fuel available
- use a fuel log during flight to provide a record of fuel consumption from each tank and assess remaining fuel on board when refuelling
- be fully familiar with the fuel system’s operation.
More information on fuel management can be found in the ATSB research report, Starved and Exhausted: Fuel management aviation accidents (AR-2011-112).
Methods for cross-checking fuel on board before flight are published by the Civil Aviation Safety Authority in Advisory Circular AC 91-15 Guidelines for aircraft fuel requirements.
About this report
Decisions regarding whether to conduct an investigation, and the scope of an investigation, are based on many factors, including the level of safety benefit likely to be obtained from an investigation. For this occurrence, no investigation has been conducted and the ATSB did not verify the accuracy of the information. A brief description has been written using information supplied in the notification and any follow-up information in order to produce a short summary report, and allow for greater industry awareness of potential safety issues and possible safety actions.