Ben Owen
FOAM-FILLED FUEL CELLS CAN SAVE YOUR LIFE!
Post-crash fires occur all too often, and have been occurring ever since the first years of powered airplane flight. But there is no need for fatal airplane fires to continue. Most currently installed, welded aluminum fuel tanks can be replaced by safety fuel cells that have been proven in race car applications for over 20 years. Countless lives have been saved because most racing car organizations have mandated the use of foam-filled safety fuel cells in race cars. The same could be true if airplanes would be equipped with these same fuel cells. If you watch auto racing, you will often see a race car hit the wall at 150 mph or faster, and the driver walks away unhurt. Twenty-five years ago, before fuel cells were used, he would likely have died in the post-crash fire of his race car. Wouldn't it be much better for aviation if we quit using explosionprone aluminum fuel tanks and started saving lives by using fuel cells? The cost of a fuel cell is the same as for an aluminum tank. Both versions presently cost about $250 for a 15 gallon capacity tank. The weight of a 15 gallon fuel cell is 15 pounds, versus 10 pounds for a welded aluminum tank, so you would add 5 pounds to your airplane. Safety fuel cells presently come in square and rectangular shapes, but are available in ANY shape imaginable if you pay extra for a custom-made design. In my own "Finchbird V-6" airplane I am using a 15 pound, 15 gallon $250 fuel cell in place of a 9 pound, 17 gallon, home fabricated aluminum tank. It is possible for me to custom-build a safety fuel cell myself that will fit in the same fuselage location and will hold 16.7 gallons, and if I build it myself, it will cost less than $100. The foam packing for the fuel cells costs
by Richard F. Finch, EAA 102503 Technical Counselor 1143, EAA Chapter 866 340 Birch St. Titusville, FL 32780
A plywood mock-up of the author's original design homebuilt has a 15 gallon race car fuel cell. This fuel cell costs $250 and weighs 15 Ibs. Hopefully, all private aircraft will change over to explosion proof fuel cells in the near future.
production-type fuel cells would have to be FAA approved on an individual airplane basis until such time as some forward thinking company should STC safety fuel cells for production airplanes. Composite airplanes with integral fuel tanks are not easily adaptable to safety fuel cells, but builders of these airplanes could at least pack the fuel tanks with the 2% density foam to prevent fuel splash and explosion caused by the airframe cracking during hard landings. Fuel cell construction is relatively simple. Cycloac plastic, the kind that can be hit with a sledge hammer without damage, is used for the tank itself. Inside the tank, a plastic foam that resembles a fine mesh kitchen scouring pad is used to prevent sloshing and to suspend the fuel (like water in a sponge). The filler neck is also equipped with a flapper valve that prevents fuel leakage in case the tank becomes inverted. These safety fuel cells are not affected by alcohol, auto fuel, nitromethane or av-gas. Ready-made fuel cells come in sizes from 3 to 44 gallons, and can be purchased from the following companies: ATL (custom fab tanks, foam, etc.), Spear Road, Industrial Park, Ramsey, NJ 07446, phone 1-800/5265330 or in NJ 201/825-1400; Scribner Engineering (stock sizes only), 9621 "I" Gates Dr., Unit D, Sacramento, CA 95827, phone 916/364-5151.
Note: Race car type fuel cells are about $25 per cubic foot, and displaces about 2% of its external dimensions. In a 10 gallon tank, the foam packing takes up about .2 gallons of space. Even production airplanes, such as Cessna 150s, 172s, the Piper Cherokee series, and any airplane with a removable fuel tank or tanks could easily be converted to fuel cells. Of course, these
substantially different from the existing perforated aluminum foil. The shredded aluminum foil basically prevents fuel slosh, but will not retain fuel. The foam "packing" in race car type fuel cells will actually retain fuel by molecular adhesion or capillary action. Shredded aluminum fuel tank baffling material is not approved for auto racing applications. SPORT AVIATION 59
