Fuel crunch: Air Force energy-saving plans face technical, financial hurdles.

The Air Force is proposing new measures to cut aviation fuel consumption by 10 percent within the next six years. Among the initiatives is to substitute up to 50 percent of the fleet's conventional fuel with synthetic alternatives by 2016, officials said.

The plan, which would affect the service's 5,700 aircraft, is intended to help the United States becomes less dependent on imported oil, Air Force Secretary Michael Wynne said at a recent conference. Wynne cited tensions with oil-producing countries such as Iran and Venezuela as a reason why the United States should reduce its consumption of fossil fuels. "The leaders of both countries have serious issues with the United States," Wynne said.

Besides political ramifications, the cost of foreign oil has had a notable financial impact on the service.

The Air Force in 2006 exceeded its budget for aviation fuel by $1.6 billion, and by $1.4 billion in 2005. These overruns were mostly the result of a "dramatic spike in the price of fuel," said William Anderson, assistant secretary of the Air Force for installations, environment and logistics. There was also an increase in energy use, he said.

When the price of a barrel of oil increases by $10, it costs the Air Force about $600 million annually; Wynne said.

In 2005, for example, the Pentagon purchased 133 million barrels of oil, for the entire year. By comparison, the United States consumes 21 million barrels of oil per day, 14 million of which are imported. The Defense Department is the largest single consumer of fuel in the United States, even though it expends only 1.8 percent of the country's total transportation fuel.

Aviation operations account for 95 percent of fuel use by the Air Force; the service uses 2.6 billion gallons of aviation fuel every year, Anderson said in an interview. To conserve 10 percent--or 260 million gallons annually--the Air Force has created several fuel saving initiatives under its policy.

The policy recommends increasing the use of flight simulators as a substitute for live flying. "Quality simulation can often provide higher quality training than training routinely available in aircraft," the policy said. It directs Air Force major commands to track total hours of simulator use per month and to identify training "that can reasonably be accomplished in the simulator."

Modifications to flight routes and efficient cargo loading also are recommended as fuel-conservation techniques. Anderson said the Air Force will try to ensure that cargo airplanes are loaded to capacity before they take off. This means an aircraft may wait a day or two to transport cargo rather than waste several half empty flights.

Yet this rule will never apply when injured soldiers or critical supplies must be sent immediately, Anderson added. The Air Force is also eyeing more en route fuel stops to replace in-flight refueling, which is "an order of magnitude more expensive" than ground fueling, the policy said.

When possible, airplanes will seek to fly more direct routes, Anderson explained, although it may at times require permission from foreign countries.

On the technology side, the Air Force is moving ahead with engine modernization programs to increase their efficiency. All KC-135R refueling tankers have upgraded engines. The C-5 heavy lift transports were expected to get new engines, but the effort has been plagued by delays and management problems. The Government Accountability Office said that the C-5 re-engining program "did not demonstrate design stability before entering the system demonstration phase." GAO estimated that design issues will increase costs and delay the program by two years.

A simpler way to cut fuel use is to fit some airplane wing tips with "winglets," Anderson said. Winglets--developed by NASA--are small airfoil wing attachments that reduce drag as an airplane moves through the air. They can also increase cruising speeds and help the airplane fly higher. Winglets can increase fuel efficiency by about 3 percent, Anderson noted. The Air Force may consider adding winglets to many of its aircraft, he said. "We have to weigh costs versus efficiency."

The Air Force also has high hopes for the blended wing body aircraft that is being developed by NASA, Boeing Phantom Works, and the Air Force Research Lab at Wright Patterson Air Force Base, Ohio. Dubbed the X-48B, the airplane is triangular shaped and made mostly of lightweight composite materials. It will get up to 30 percent better fuel mileage, the Air Force said, because of its center body shape that creates more lift than a traditional airplane.

The aircraft finished wind tunnel tests in May 2006. It was scheduled to start flying at NASA Dryden--NASA's flight research center in California--in April 2007, said George Muellner, president of advanced systems at Boeing. Although still in the early phases, the wing body design could be used for tanker, transport, bomber and surveillance needs, the research lab said.

In a separate effort to reduce reliance on foreign fuel, the Air Force will seek within the next decade to substitute 50 percent of its aviation fuel consumption with a synthetic blend produced domestically, Wynne said.

"To provide an assured source of fuel ... we are particularly interested in making synthetic aviation fuel," he added. Right now the market for these fuels is relatively immature. There are no commercial companies in the nation working on synthetic fuels, Anderson said. "Companies such as Syntroleum, Rentech and Baard Energy are all in the alternative energy business, but none of them has an operating commercial synthetic fuel plant in the United States," said Paul Bollinger, an Air Force spokesman.

"We are watching the market, listening to commercial producers" who come up with new technology, Anderson said.

To date, the Air Force has completed two much-publicized B-52 bomber flight tests using synthetic fuel developed by Syntroleum, based in Tulsa, Okla. The company has since closed its Tulsa plant, Bollinger said. The first flight--in September 2006--used a 50/50 blend of JP-8 jet fuel and synthetic fuel in two of the bomber's eight engines. The fuel was derived from natural gas using a conversion method called Fishcher-Tropsch. The most recent test in December 2006 used the 50/50 blend in all eight engines.

Since the bomber test, Air Force Combat Command has shown interest in a similar test with a fighter jet. Before it attempts such a test, Anderson said, the Air Force will try to fly a C-17 Globemaster transport powered by synthetic fuel. Testing will start "a few months from now," Anderson said. "We will definitely test a fighter aircraft, but they have after burners; it's a different issue."

The C-17 was chosen because the engine is similar to that of a commercial airplane, Anderson said. The Air Force is working with the Federal Aviation Administration to find synthetic fuel to fulfill both military and commercial needs. The Air Force, Defense Department and Department of Energy are all contributing to the FAA's commercial aviation alternative fuels initiative.

Two studies will be released in September, said Marion Blakey, FAA administrator. The studies will examine the feasibility, cost, technical issues, barriers, and environmental issues associated with synthetic fuels.

The partnership between the Air Force and the FAA goes beyond the alternative fuels studies. The FAA's buying power represents 85 percent of the market, Wynne said, so the agency is an essential component of a successful synthetic fuel industry.

The Air Force is seeking industry bids, through the Defense Logistics Agency, to buy 206,000 gallons of synthetic fuel this year for testing, said Anderson. NASA also issued a bid for 9,000 gallons of the fuel for its own testing program.

Wynne is exploring a range of other potential fuel sources, including coal and biomass. He noted that power companies are planning to build 150 U.S. coal plants to meet growing electricity demand. But the biggest obstacle to coal production is carbon dioxide emissions. The Air Force is working with the Energy Department to develop carbon capture technology, or carbon sequestration.

The Air Force is considering mixing biomass and coal to reduce carbon dioxide emissions. But the energy content of biomass is relatively low for jet fuel use. The Department of Energy is looking for a high-energy mix of the two substances, Wynne said.

Many of the Air Force's conservation plans are dependent upon technology development and commercial programs that are still immature. Yet officials stress that they intend to remain committed to the energy-saving goals. "This is not the flavor of the month ... this is something the Air Force has gotten its head around," Anderson said.

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