Robinson Helicopter Company and CASA have issued an Airworthiness Bulletin encouraging owners of R22 helicopters to replace their metal fuel tanks with bladder-type tanks.
Issued today, CASA AWB 28-017 reflects the latest service bulletin (SB) from Robinson, which states all R22 aircraft need to complete the modification to increase the aircraft's resistance to post-impact fire in the event of a crash.
Several accidents in Australia involving the larger Robinson R44 have led to fatalities caused by fire after an impact that was initially thought to be survivable. Metal fuel tanks were found to have split on impact, spilling fuel onto hot engine components.
The Robinson SB calls for the tanks to be replaced in R22s as soon as practical, but no later than the next 2200-hour overhaul, 12-year inspection or 15 January 2020, which ever occurs first.
CASA is encouraging owners to adopt the " as soon as practical" approach to compliance.
"The design features introduced by Service Bulletin SB-109A increase the level of safety in the event of a survivable crash by either decreasing the likelihood or delaying the onset of post-crash fire," the AWB states.
"The features minimize crash-induced fuel leaks and their contact with potential fuel ignition sources both during and after the crash, and increase the time occupants have available to egress before a post-crash fire could become critical.
"CASA strongly recommends that all operators of RHC R22 helicopters incorporate the ... modification ... at their earliest convenience."
There are around 600 R22s on the Australian Civil Register, operated mostly in training and on pastoral properties for cattle mustering.