UTAH TEST AND TRAINING RANGE — Cruising at 21,000 feet isn't as peaceful as you might think.

After all, this isn't a commercial airliner. This is the military, where things are big and loud.

But big is part of the job description when you're a flying gas station.

Actually, the KC-135 Stratotanker's crew hates when you call it that.

The tanker is easily one of the U.S. Air Force's most popular planes. It's not flashy like the F-16. And it's not the biggest plane, like heavy-cargo aircraft.

It's a workhorse, and it gets really popular when thirsty jets line up for much-needed fuel.

Sometimes fighter pilots are screaming for fuel, said Tech. Sgt. Derek Larson, with the Utah Air National Guard's 151st Air Refueling Wing. And that's when the KC-135 becomes an airborne command, deciding who gets fuel and when they get it.

Flying over the Utah Test and Training Range — the largest block of supersonic airspace in the United States — things were more serene Wednesday, though still so loud that earplugs were needed and crew and passengers had to shout to be heard.

Outside the tanker, F-16 pilots from Hill Air Force Base maneuvered their planes in orderly fashion to suck the nectar of life from the big bird in the sky.

Larson, laying on his stomach and looking out a window in the bottom of the KC-135, used a joystick to align a boom with the fuel intake on each F-16.

For just a minute, the two planes were connected as the KC-135 pumped fuel at a rate of 2,000 pounds per minute while flying at 362 mph.

Larson said it's possible for a tanker to continuously pump fuel to a wounded plane, essentially towing it to safety.

That's not a problem when you carry 200,000 pounds of fuel and have only a few planes to service — like Wednesday, when Mace, Badger, Thud and Whiskey each got their fill and went back to training.

But for the heavies — cargo planes such as the C-17 or C-130 — it can take two tankers to fill each one.

That's why the pilots — Capt. Zac Love and Maj. Brandon Taylor — need Larson. He's their eyes at the back of the plane.

Never mind if some people say Larson lies on his belly and passes gas all day. It's true. He's on his stomach while planes get their fuel. But he jokes that the pilots are just the bus drivers who take him to work every day.

Jokes aside, the KC-135's crew members say they have a hard time calling what they do a sacrifice for their country because they love it so much.

In their combat support for wars in Iraq and Afghanistan, the men experience relatively little danger, because there's no air force opposing them. So their tours, such as their recent two-month deployment to Turkey, give them plenty of flying time.

"I love to fly," Love said. "I love the mission. I love serving my country."

And being in the National Guard allows the men to stay at home in Utah between deployments without worrying about transfers around Air Force bases worldwide.

"It's the epitome of citizen soldier," Larson said, adding that he'll keep flying the boom at the back of the KC-135 "for as long as they'll let me."

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