A yellow model airplane called Thor took off into the sky, guided by a pilot with a remote control on the ground. Once it reached a safe trajectory, he flipped a switch and no longer needed to control it.

Thor flew by itself.

The Unmanned Aerial Vehicle research group is the University of Minnesota’s drone lab. They don’t fly the large, jet-sized planes from the movies — instead they’re researching the low-cost versions that are much smaller.

Whether the U.S. military should use drones is highly controversial, but Peter Seiler, a professor with the UAV lab said they focus on the positive applications like surveillance during natural disasters, managing fertilizer on farmland and tracking animals in wildlife reserves.

“I think there are numerous applications where low cap cost aerial vehicles could play a role,” he said, “but right now there’s no avenue to actually get these aircraft to fly in the airspace — it’s not allowed.”

Currently, the Federal Aviation Administration only authorizes research groups to fly drones in a specific place for a specific purpose. The agency will change this policy to allow UAVs to fly in the national airspace by 2015, according to a press release on the 2012 FAA reauthorization.

Thor is the lab’s main experimental UAV, and it only weighs about four pounds.

Andrei Dorobantu, the lab’s summer project lead, said this affordable alternative makes for easy deployment. All they need to fly Thor is a laptop, a remote control, a bag full of modems and wires, and two people.

“That’s the best part about it. If we want to fly, we just go,” Dorobantu said, though he added they can only fly if weather permits.

This particular Friday, they performed straight-line control tests. Will Johnson, the lab’s software lead, said the day’s breeze was actually welcome during the test because he programmed Thor to adjust to turbulence when flying in a straight line.

 It was a successful flight test.

After the test, the five men got to “play” with an old plane named Odin. They use Odin as a training plane for new pilots because it is less valuable since they took the computers out of it.

But for Arion Mangio, flying is nothing new. In addition to being able to fly model airplanes, he has an pilot’s license and plans to attend the Air Force Academy next May.

As the trainer plane took to the sky, Mangio made it do flips and twists.

They would never do acrobatics like that with one of their UAVs, Dorobantu said, because they are too valuable.

In addition to the extensive safety checks before flight tests, he said they have even programmed the UAVs to know if they lose communication with the pilot on the ground.

Dorobantu said in that situation, the UAV knows to crash dive.

They also said they never want to lose sight of the UAV when it is in the air. Dorobantu said the remote control can communicate with the aircraft up to a mile away, but they keep the UAVs above their heads for safety.

 “Any potential benefits are invalidated if the UAVs are not safe,” Seiler said.

 Though their drones cost thousands of dollars — compared to the millions NASA and the military spend — Dorobantu said the long hours they spend writing lines of code to program the software is worth much more.

Writing the code themselves makes it more efficient in the long run, he said, because it means they understand how to make things easier for themselves. Dorobantu said if they want to fly a UAV other than Thor, they only need to change one line of code.

“Really, a lot of things are changing. But from your point of view, it’s just one thing,” he said. “That’s a big deal.”

Ramin Geshnizjani, a visiting graduate student from Germany, is working on designing systems that can adjust to changes in the air.

His research is for satellites, but he said it is the same regardless of the hardware.

“It’s basically just math,” Geshnizjani said.

He said he came to the University because Gary Balas, professor and head of the aerospace engineering and mechanics department, is a leader in the field of control systems. Balas is one of three faculty members who are involved with the research group.

Another area the lab is researching is fault detection. If something gets stuck in one of the holes in a pressure probe for example, the aircraft could misjudge its speed and crash.

They are working on developing algorithms that will allow the aircraft to detect this fault and correct it.

By the end of the summer, Dorobantu said he would like to see the UAVs be able to fly to specific GPS waypoints on their own.

He said they would also like to find a new lab director. Austin Murch, former lab director, left the University in late May to take a position with Kestrel Aircraft.

The lab has a pending partnership with an aircraft part manufacturer that wished not to be named. The legal departments are currently working out the intellectual property details, Dorobantu said.

Since the company wishes to do research for the military, the work will not be open source. One of the goals of the UAV lab is to develop open source, free knowledge.

“We are completely open source and public domain,” Dorobantu said. “From our website, you can literally download every line of code.”

Another problem they face is the Minnesota climate, since they have to fly all year to continue their research. On one winter day, batteries not working in the cold were an issue, Dorobantu said.

“We actually completely lost power and had to glide the aircraft down,” he said. “We were kind of nervous there.”

Being able to fly so easily makes up for the few mishaps, they said. The five men at the airstrip beamed as Odin landed safely on the ground.

“I grew up loving airplanes,” Johnson said. “It’s the best thing I could do in college.”