The Australian Transport Safety Bureau encourages all operators and owners of R44 helicopters that are fitted with all-aluminium fuel tanks to note the circumstances of this accident as detailed in this preliminary report. It is suggested that those operators and owners actively consider replacing these tanks with bladder-type fuel tanks as detailed in the manufacturer's Service Bulletin (SB) 78A as soon as possible.
In addition, the ATSB highlights the existence and content of SB 82 that aims to reduce the chance of the rotor brake switch as a possible ignition source in the event of a fuel leak.
On 21 February 2012, the helicopter manufacturer released Service Bulletin (SB) 78A that brought forward the date of compliance as stated in SB 78 from 31 December 2014 to 31 December 2013.6
In conjunction with the United States Federal Aviation Administration, the manufacturer is also examining other methods to ensure greater compliance with that upgrade while taking into account the rate at which the bladder-type fuel tanks, and the other associated components, are able to be manufactured. The issue of an Airworthiness Directive is being considered.
On 21 February 2012, the manufacturer also released SB 82 that required the replacement of the rotor brake switch to reduce the chance of a possible ignition source in the event of a fuel leak.7 The stated time of compliance was 'within the next 150 flight hours or by 31 May 2012, whichever occurs first'.
The Australian Transport Safety Bureau (ATSB) generally proposes corrective or precautionary action in response to an occurrence only where it is justifiable on the basis of established or probable facts. Although work remains to be done to establish the facts of this accident fully, the circumstances are consistent with the consequences of the accident being significantly exacerbated by the fuel-fed fire.
The ATSB therefore draws the attention of all R44 operators to the following advisory notice, on the basis of prudence, until such time that the mechanism(s) contributing to the accident are fully established and understood. All R44 operators will receive a copy of this report and advisory notice.
