The Forest Service team in San Dimas studied the airship plans and found that the artificial rain dropped from a blimp might dissipate before it hit the ground, Bambarger said. And because blimps move so slowly, 20 blimps would be needed in the Los Angeles region alone to make sure one was within range of a fire.
At an estimated $60 million a pop, Bambarger said, "It doesn't make economic sense to have a watering can that does the same thing as the aircraft we already have."
Other well-intended inventors have submitted what they hoped were cutting-edge proposals, such as using halon gas instead of flame retardant foam because the gas leaves no residue. Good idea, Bambarger said, except that halon has been outlawed because it can be 10 times more damaging to the ozone than chlorofluorocarbons, a better known ozone destroyer.
When it comes to innovative firefighting, said Forest Service Specialist Ralph Taylor, the ideas more likely to reach production are subtle.
Fire trucks throughout the West now use 60 to 100 "collapsible Whiffle balls" in their water tanks to prevent the entire rig from tipping over on hills. The balls, submitted as a prototype last year, keep water from sloshing around and cost about $2 each.
Last year also brought the $3.50 hose sock, a mesh filter that protects small animals and fish eggs from being sucked into a tank when a truck is refilling from a stream.
But some high-tech gadgets do make the cut now and then.
In 2001, the Forest Service and Encinitas-based Space Instruments Inc. began testing an infrared system for determining quickly the hottest spot of a fire after a lightning strike.
Two such systems are now mounted on fire patrol planes and more are planned for next year. The National Weather Service could already pinpoint a lightning strike, but the new equipment gives firefighters more accurate readings. And it doesn't require a blimp.