"It's tough to explain, for somebody," he adds. "It's really just getting a feel for what both aircrafts are doing and there's a lot of forces fighting against you."
The process allows the C5 to stay in the air longer and cut down on valuable time that would be spent on the ground refueling.
Grass says the purpose of our training mission is to make sure they're successful for when they do it for real.
Boom operators also have other responsibilities besides fueling aircrafts, including cargo loading and passenger transport.
"For humanitarian efforts, it's a lot of cargo we're bringing a lot of aid to places that need it," says Grass.
The guard has completed a number of humanitarian missions delivering help to hurricane ravaged areas in Puerto Rico following the large amounts of hurricanes and natural disasters that happened in the past year.
"I didn't join the Maine Air Guard not to help people," he says. "I'm a local grown boy, I've always seen these planes flying around and I just like being part of the big picture of things here."
"I think that's what makes 'Maine-iacs' great," says KC-135 Pilot, Captain Nathan Ayer. "The fact that we're willing to step up and do that anywhere in the world."
Stepping up is nothing new for the Maine Air Guard, having previously won the Air Force Outstanding Unit Award in 2014.
They are currently looking for exceptional men and women to join the team.
"If you're ever looking for an opportunity to extend your career or even have a side job on the side maybe even serve your state of Maine, if not your country, come on out ask, some questions and we'll see what we can do for you. There's plenty of jobs out here."
We began our descent back to the base around 1400 hours.
Rest assured, our experience with the "Maine-iacs" will not be forgotten.
You can find more information on how to join the 101st Air Refueling Wing by visiting the Maine Air Guard's website.
To watch part one, click here.