There are three compelling reasons why pump and chainsaw gas should not be carried in the tailboom on Bell 204's 205's and 212's.
Operationally there are so many occasions where an Initial Attack crew is being dropped of on a beaver dam or the edge of a rock outcrop where the tailboom cargo area is just not accessible because the tail is out over a lake or beaver pond. The result is that the crew is on the ground to action a fire with everything they need to fight the fire except for the pump gas. This necessitates the helicopter leaving the scene to go and find a spot to land where the pump gas in the tail can be moved to the cabin either by the pilot or the HO if there is one and returning to the location where the crew was dropped off to give them their gas. But now there may be empty hose bags or other loose articles on the ground to get caught in the rotor system along with the firefighters themselves creating a more difficult landing. It should be mentioned that on initial attack in an effort to get the IA crew close to a fire the pilots will go into places he normally would not. Asking him to do it twice just to drop off the fuel that was in the tailboom, but inaccessible is unreasonable and ultimately hazardous.
The cargo compartment in the tailboom is a non ventilated space that is only 4 feet away from the 400 degree C exhaust of the powerplant. It takes very little leaked fuel within the cargo compartment to produce just the right proportions of air and gas to create an explosive mixture. Not only is there the hazard of the fuel/air mixture being ignited by the hot exhaust but it is very common for hand tools to be carried in the tailboom along with the jerry cans. Most hand tools are hardened carbon steel and very capable of producing a spark capable of igniting gas vapors.
A third scenario exists where the C of G of the helicopter will move out of the operable limits and create a situation where the pilot will run out of forward stick and loose control of the aircraft rolling backwards until the aircraft is inverted. If for example 2- 5 gallon jerry cans are in the tail and a hover exit is being conducted with just the pilot left in the aircraft this limit would be reached. 212's would reach the fatal 'out of C of G' condition before the 204 or 205.
None of the aforementioned examples are extreme. Any one of them could happen any time the fuel is carried in the tailboom cargo compartment. It is argued that keeping the fuel in the cargo compartment makes for a safer passenger compartment, which may be true in the case of a crash. It is also argued that the fumes from a leaky tank will nauseate folks on board. I think most pilots would choose to know that there is a leaky gas can on board and deal with it rather than flying around with a gas can filling up the cargo compartment with raw gas and a fuel-air mixture.
So let's firstly use gas cans that don't leak, put them up front where they are easily accessible and the weight of them does not adversely affect the C of G.
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