Regulatory guidance regarding the measurement of fuel quantity before flight lacked clarity and appropriate emphasis and did not ensure that the fuel quantity measurement procedures used by operators included two totally independent methods.
On 26 September 2008, CASA advised:
The status of CASA's review of its guidance material relating to separate processes for fuel quantity measurement checks
The second edition of the Air Transport Communication (AT com)20 advised of impending amendments to Civil Aviation Advisory Publication (CAAP) 234. In amending CAAP 234, clear guidance will be given to industry regarding the two independent means of ensuring the correct amount of fuel is onboard an aircraft. The amended CAAP 234 will emphasise the responsibilities of the Pilot-in-Command and the operator in adhering to the manufacturer's guidance in determining the amount of fuel onboard an aircraft.
CASA would like to emphasise the point that crews utilise all means provided by the manufacturer to ascertain correct fuel quantity. In this instance there was a manufacturer's recommended procedure that aircraft fuel quantity is independently confirmed using a separate facility incorporated into the aircraft. Had this crew followed that guidance, the incident would not have experienced its near catastrophic outcome.
The second edition of the AT com advised industry that changes to CAAP 234 were forthcoming. The AT com is intended as an informal means of raising topical issues inclusive of alerting operators of intended changes. CASA is not reliant on it to convey the information as variations documentation is undertaken through our formal process. The process of amending CAAP 234 is currently being undertaken and this involves detailed consultation with various stakeholders.
A summary of any changes to CASA regulatory oversight activities relating to fuel management or fuel quantity cross-checking processes. Fuel quantity cross-checking processes have been added as a distinct element within operational surveillance activities. Where a deficiency in the fuel cross checking procedures is identified, it is raised with the operator. The matter remains under close scrutiny until resolved to the satisfaction of CASA
The ATSB is concerned that, at the time of publication of this report, the CAAP 234-1(1) amendment had still not been released. The ATSB will continue to monitor the progress of the CAAP review. In addition to the occurrence involving VH-XUE, the ATSB is aware of two other occurrences involving Australian-registered aircraft since January 2005 involving engine power loss due to fuel starvation in turboprop aircraft with a maximum take-off weight (MTOW) above 5,700 kg.
In each case, the practices used by the flight crew to establish fuel quantity did not detect erroneous fuel quantity indications. The operators involved subsequently amended their procedures to include dripstick checks as a mandatory part of their procedures for establishing the quantity of fuel on board the aircraft. It is possible that there are other examples among turboprop operators of aircraft with a MTOW greater than 5,700 kg where the procedures used to determine the quantity of fuel on board the aircraft do not include independent, comparative checks of fuel quantity.
On 14 September 2007, the ATSB issued AO-2007-017-Safety Advisory Notice-013, which stated: The ATSB suggests that all turboprop operators take note of the following safety issue and review their processes accordingly: The processes used by some turboprop operators for checking the fuel quantity on board prior to flight have not used two methods of sufficient independence. In particular, the practice of using a comparison of a gauge indication after refuelling with the gauge indication prior to refuelling plus the fuel added is not adequate to detect gradually developing errors in gauge indications. On 25 February 2008, the ATSB advised CASA and all Australian operators of EMB-120 aircraft of the investigation report regarding the EMB-120 engine power loss occurrence in Europe on 20 February 2008. In the meantime, the ATSB re-emphasises AO-2007-017-Safety Advisory Notice-013 (above), which was initially issued on 14 September 2007.
