"Fill it all the way up," Richard Fleck instructed Ryan Townsend when the Cardinal Air Center fuel truck pulled up to Fleck's small V-tailed airplane one morning last week.

Fleck jotted down the number of gallons Townsend pumped into the plane — about 45 gallons of 100-octane low lead. He did a few calculations and determined the plane had gotten what he called a "pretty good" 10 gallons per hour on a return trip from Bend, Ore.

Fuel efficiency aside, that fill-up cost Fleck more than $260.

Full-service fuel of that type from the fixed-base operator was going for $5.80 per gallon; self-serve was $5.19. A year earlier the same vendor was selling self-serve for $3.99 per gallon.

Just as motorists have been affected by rising gasoline prices, pilots have been affected by increases in the cost of aviation fuel. The result?

"They don't fly planes for no reason anymore," Fleck said.

Fuel vendors at Ventura County airports reported prices of 100 LL and Jet A fuel that ranged from $5 to $7 per gallon in early July. Their suppliers are the same as automotive fuel suppliers — BP, Chevron, Exxon Mobil, Shell and Phillips 66.

Steve Lee, general manager at Golden West Jet Center at the Oxnard Airport, said the $6.18 and $6.65 his fixed-base operator was charging on July 2 for 100 LL and jet fuel, respectively, was up about $2 from a year ago.

The increasing price is beginning to sink in with pilots, Lee said. He saw about a 20 percent decrease in business in June, compared to June 2007.

"Up until last month, we were doing about the same, maybe even a little more. This last month, it's definitely a noticeable decrease," he said.

Total operations at Camarillo Airport, where there are four fuel vendors, went down by 10,000 operations — takeoffs or landings — in 2007 compared to 2006, said General Manager Aaron Walsh.

Cardinal offers prepaid gas card

At Oxnard Airport, operations went down by 9,503, according to General Manager Jorge Rubio.

Santa Paula Airport does not count operations, said General Manager Rowena Mason. However, the airport itself is the sole fuel vendor, and Mason said that about 4,000 gallons more were sold in both April and May of this year than in the same months last year.

Fuel for piston-powered airplanes at Santa Paula Airport's self-serve island was $5 per gallon on Monday of last week, which according to AirNav.com, a Web site that provides airport information for pilots, was the cheapest fuel at any of the three airports that day.

"We get a lot of transient people coming in just for the fuel," Mason said.

The desire for a bargain is also evident at Cardinal Air Center, the only fixed-base operator at Camarillo Airport with a self-serve option. The self-serve — which requires customers to taxi up to an island and fuel their planes themselves, as opposed to having a fuel truck meet them and an attendant pump the fuel — was 61 cents cheaper on July 7 than full-service. Only 100 LL, not jet fuel, is offered through self-service.

Cardinal Air Center owner Larry Oyres said the self-serve option is more popular by about three to one.

"We price that aggressively, so if a guy's going to buy 50 or 70 gallons of gas, that's a chunk of change," Oyres said.

Cardinal offers a prepaid gas card, which allows the operator to avoid paying fees on credit card purchases. The price of self-service 100 LL is a dime a gallon cheaper when purchased with the card.

"I was really surprised by how many have taken advantage of it," Oyres said. About 200 people have gotten cards.

Still, business at Cardinal was off by 22 percent in June compared to the previous June. Oyres thinks fewer people are flying because of the cost.

"They're not flying as much, they're not flying as long," he said. "They're sitting around in the hangar telling hangar stories instead of going out."

One group of pilots who did go out on July 3 were Gery Moret, Jim Barton, Jay Levine and Richard Norris, all of Los Angeles. They flew from Santa Monica Airport to Camarillo Airport for what pilots refer to as the "$100 hamburger" — a day of flying with lunch in a distant town.

Instead of hamburgers, the four ordered salads at the airport's Waypoint Café. Instead of paying $100, they estimated the fuel eaten by Moret's Cessna 335 totaled $400.

"Does that come with mustard?" Levine quipped.

"We're going to brag about the $400 hamburger," Barton announced defiantly.

Moret said the effect of rising fuel prices was evident in the fact that all four were standing beside one airplane that afternoon. Pilots are reluctant to pass up the opportunity to fly themselves, he said. Moret recalled flying up to Santa Barbara once during the 1970s for lunch with some fellow pilots. The 15 people took 13 airplanes.

But now that costs have risen, "we go with the richest guy," Norris joked.

Others also are feeling the pinch.

Decreased number of air shows

The higher costs are reflected in the decreased number of air shows the Commemorative Air Force is invited to, said Jim Tierney, a historian with the organization. Air shows typically pay a fee and provide a free tank of fuel for airplanes that are invited to appear.

The Commemorative Air Force has a museum at Camarillo Airport and cares for several World War II-era aircraft, including Camarillo Commando, a Curtiss-Wright C46 cargo plane that was built in 1944, saw service in Asia and is now the city's official airplane.

It burns about 300 gallons per hour at top speed, Tierney said. Fuel has become the single biggest item in the Commemorative Air Force's budget.

This year the Commemorative Air Force may attend six to eight shows, Tierney said, down from 12 or 16 in years past.

The effect of higher fuel prices on businesses based at Ventura County's airports is mixed. Owen Barnhart, line services manager at Channel Islands Aviation, said the Camarillo Airport fixed-base operator has not had to raise prices at its flight school or charter service to the Channel Islands.

Lili Dellinger, customer service manager at Avant Air, also at Camarillo Airport, said business has steadily improved since the operator opened last year.

Prices cost pilot his plane

At Oxnard Airport, there were 42,955 total operations from Jan. 1 to May 31 this year, Rubio reported, compared to 31,029 during the same period in 2007. Rubio said all operations were down except for the airport's flight school, which accounted for the increase.

While some pilots are responding to rising costs by spending less time in the sky, Bill Richardson gave up on owning an airplane. Fuel prices were a factor in his decision to sell the Cessna 182RG he had owned for 11 years. He kept the plane at Oxnard Airport until its sale last December.

Toward the end, he used it exclusively to meet with clients of Micro Solutions, a computer consulting business for which he is vice president of sales. Facing fuel prices of up to $8 per gallon at some airports, as well as a looming engine rebuild, he realized he simply couldn't afford it.

"I'd been dragging my feet on it for about six months. I just woke up one day and said, I can't justify it,'" he said. "When it came to, Can I put gas in my car or my airplane?' I had to choose my car."

Giving up the airplane was tough, Richardson said. He recalled how one night, while flying back to Oxnard from Sacramento, he directed his airplane into a trough in the clouds while the moon shone overhead.

"This is what angels must see," he said. "It's a tremendous sense of freedom and a tremendous sense of personal expression."

For Mason, that experience isn't worth giving up, even at a time when both automotive and aviation fuels are costly.

"I stopped driving my car, but I haven't stopped flying my airplane," she said. "I ride my bike to the airport so I can fly my airplane."