Steps are being taken to correct conditions that allowed water to get in the fuel tanks of several Los Angeles City Fire Department helicopters at Van Nuys Airport, grounding most of the fleet for several hours, department investigators said Thursday.
Assistant Fire Chief Jerry Schnitker said the 4 p.m. Tuesday incident, in which four of seven helicopters were grounded, was "clearly mechanical error. The whole things sounds bad, and it is bad, but we've made the necessary corrections."
Water mixed with fuel could cause the engine of a helicopter to sputter and possibly die, endangering the lives of firefighters and anyone on the ground below, Schnitker said.
Although the problem was discovered shortly after a 100-acre brush fire broke out in the La Canada Flintridge area, fire officials said it did not hamper their efforts.
"We were maxed out on helicopters, didn't need any more," Glendale Fire Department Assistant Chief Richard Hinz said.
Problem in Storage Tanks
Schnitker said the problem was traced to condensation that occurs naturally within four 2,000-gallon fuel storage tanks. There was a three-inch layer of water on the bottom of the tank, he said.
A pipe that normally draws fuel from the top of the tank had probably slipped so that it was pumping fuel from the bottom, where the water had formed, Schnitker said.
Schnitker said that pipe and others will be shortened so that, even if they do slip, they cannot reach the bottom of the supply tanks. Officials also will try to devise a way for firefighters to check the accumulation of water, he said.
Filters that normally signal when water is mixed with fuel apparently malfunctioned, Schnitker said. Those filters have been replaced, and the old ones are being examined, he said.
The water in the fuel tanks was discovered during a routine maintenance check of the helicopters. The tanks were then drained and refilled, a process that took more than two hours.
The other helicopters were not affected because they did not need to be refueled.
While the four helicopters were grounded, two others helped drop water on the La Canada Flintridge fire, and a third handled two other fire calls in Los Angeles, Schnitker said.
"There could have been trouble if it had been a big fire day," he said. "As it was, everything turned out well."
The helicopter unit at Van Nuys Airport serves the entire city.