The U.S. Department of Defense is the single-largest consumer of fuel in the world. Despite rising fuel costs and a limited supply of oil, the military’s fuel consumption has been growing in recent years. In World War II, the armed forces used about one gallon of fuel per soldier every day. In Desert Storm, fuel usage was about four gallons. By 2007, with operations in Iraq and Afghanistan, usage was up to 16 gallons, or $3 million worth of fuel a day.
So where does it all go? To the Air Force, mostly. Jet fuel accounts for 71% of the entire military’s petroleum consumption, in part because flyboys move around the majority of men and a lot of heavy equipment. When it’s time for an Army battalion to deploy, they hitch a ride on a cargo plane through the U.S. Transportation Command (TransCom).
“TransCom is like a very large airline,” says Army Col. Vern Beatty. “When the time is right, a C-17 will land and pick you up and take you where you need to go.”
In Pictures: Fuel-Sucking Military Vehicles
The C-17 Globemaster cargo plane has a payload 170,900 pounds. Even bigger, the C-5 Galaxy has a payload 270,000 pounds; fully loaded, it gets just .07 mpg. For air attacks and ground support, the F-22 Raptor is available. Capable of sustaining supersonic speed without afterburners, the fighter jet gets an estimated .4 mpg, depending on conditions and speed, which tops out at Mach 2.
Like many military aircraft, these planes are capable of midair refueling, but that gets even more expensive. At current oil prices, it takes more than $30 worth of fuel to deliver one gallon of jet fuel to a plane in flight.
Army vehicles get better mileage, but Beetle Bailey isn’t exactly riding around in a Prius. An armored division of the Army can use as much as 600,000 gallons of fuel a day. A tank like the M1 Abrams gets about .6 mpg, and a cargo vehicle like the M-1070 semi-trailer (designed to haul tanks) gets approximately 1.2 mpg.
An Army Humvee gets between 10 and 14 mpg, about the same as the commercially available Hummer. Fuel economy drops, however, when it’s off the freeway and navigating rocky Afghan terrain.
The Navy could be considered the most efficient of the three large military branches. As Beatty points out, it’s cheaper to send equipment by sea than by air because of marine engine technology.
In 1951, Congress authorized the Navy to build a nuclear-powered submarine. Until then, submarines had been powered by gasoline engines and played only a small role in naval affairs. Nuclear subs proliferated throughout the Cold War, and today all naval submarines are propelled by nuclear reactors.
Gasoline engines still power most of the Navy’s surface vessels, such as the Arleigh Burke class of destroyers, which have 108,000 horsepower and sail at over 30 knots. But there are also some nuclear-powered ships. In 1961, the USS Enterprise became the first nuclear-powered aircraft carrier, housing eight reactors that propel the 1,123-foot ship as fast as 30 knots.
Today, the Nimitz-class aircraft carriers also run on nuclear power. Such super-carriers are essential for transporting Air Force planes economically and, when time allows, moving troops and equipment.
http://www.forbes.com/2008/06/05/mileage-military-vehicles-tech-logistics08-cz_ph_0605fuel.html
