Robinson Helicopters has been installing bladder-style fuel tanks in its R44 helicopters since 2009. But much of the fleet manufactured before then is still flying with the old-style aluminum tanks that tend to rupture in otherwise minor accidents.
Last year, following a string of needless post-crash R44 fires, the Australian civil aviation authorities grounded all R44 helicopters until their owners retrofitted them with the new bladder-style tanks. Not a bad idea.
The FAA refused to follow the Aussies' lead, saying that "R44 fuel system crashworthiness does not appear inconsistent with other similar helicopters." Because most other helicopters do not tend to explode in otherwise survivable accidents, no one was sure what the FAA was talking about. Now the NTSB is asking the FAA to reconsider and to ground Robinson R44 helicopters that aren't retrofitted with the safer bladder tanks. According to the NTSB, requiring owners to retrofit their helicopters will "prevent accidents and save lives."
It's hard to understand why the FAA is so reluctant to mandate the retrofits.