Some Valley service members are hiding in plain sight.
Just south of the runways of your flight at Sky Harbor, you'll find the 161st Air Refueling Wing with the Air National Guard.
The unit is made up of 850 members and eight KC 135 planes, and it has a global mission.
But this group is Arizona proud.
"We're here to protect our state and our nation," said Master Sargeant Bobby Steele, Crew Chief on the KC 135.
"Our objective is to provide in-flight air refueling anywhere in the world," said Colonel Patrick Donaldson, Commander of the 161st Operations Group.
For 70 years, the 161st Air Refueling Wing, based in the heart of Phoenix, has engaged in just about every major aerial combat situation involving the United States.
"From Korea, Berlin airlift, Vietnam, and for many years now, activities and operations in the Middle East," said Col. Donaldson.
The 161st serves as a gas station in the sky, providing fuel to other aircraft mid-air.
"Just the same as you would stop at a gas station on a road trip and keep pushing through, that's what we're able to do in the sky," said Caleb Mischung, Aircraft Maintenance Officer.
The 161st transfers fuels up other aircraft midflight so they can continue their missions.
For the members of this wing, it's just another day at the office.
"You're up in the middle of the sky," describes Master Sergeant Steele. "The windows open up. The boom drops. And you have aircraft coming up from underneath you waiting for gas."
The 161st's mission of supporting operations here at home and across the world is one most civilians never get to see.
"Planes in the sky means less boots on the ground," said Steele.
The wing's mission may be global.
But, as an Air National Guard Unit, each of its members is rooted strongly in Arizona.
"We live here," said Col. Donaldson. "We work here. We have neighbors and we don't typically move. And that gives us great strength."
The 161st is proud to represent Arizona.
"It was my opportunity to give back to my community and the nation," said Mischung.
"I wanted to dedicate my life to something bigger than myself," said Noemi Sanchez, KC 135 Aircraft Mechanic.
Even though you might not see their work every day, this is your guard unit.
"Next time you fly out of Sky Harbor or fly into Sky Harbor, just look south of the runway and see those big gray airplanes across on the other side of the ramp," said Steele. "That's us."