You could say that the idea came to him in a cloud of smoke.

Over the summer, Mike Logan, an aerospace engineer at NASA's Langley Research Center, put a group of students to work designing and building an Unmanned Aerial Vehicle (UAV) that could one day help to snuff out fires in Virginia's Great Dismal Swamp.

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The origins of the project go back to August of 2011. A lightning strike in the swamp sparked a blaze that ended up burning for four months. At one point, wind pushed the smoke as far north as Maryland. Logan, who lives due north of the swamp in South Hampton Roads, often found his house in the path of the acrid cloud.

"After choking down a few dozen clouds worth of peat bog smoke, which I found out I'm allergic to, I thought, you know, there really ought to be a better way," he said.

So Logan made a phone call to the local fire captain. They had a couple of conversations and visited the swamp to do a sight survey.  Logan learned that lightning causes the majority of the fires in the swamp, and that the only way swamp personnel are able to locate fire sources is to hire an outside contractor to do a manned aircraft survey.

It's an expensive solution, and one that didn't happen until nearly a week and a half after the 2011 fire started. By that time, the blaze had already spiraled out of control.

But that gave Logan an idea: why not develop a UAV that could fly over the swamp and detect fires before they get out of hand?

It was a simple solution to complex problem, and Logan tasked his student team with bringing it to fruition.

"I said, you know, this would be a perfect opportunity to give them some hands-on learning experience and oh, by the way, solve this massive problem pretty inexpensively," he said.

The team, which included Aerospace Project interns Jennifer Hull, Robert Harden, Matthew Mannebach and Coryn Mickelson, and Langley Aerospace Research Student Scholars (LARSS) intern Steven Vo, had 10 weeks to design and build the UAV. Logan specified that it had to be low cost and operable by Great Dismal Swamp personnel. It also needed to be deployable within minutes or hours of a storm and able to autonomously detect, provide images of, and provide precise GPS coordinates for, small hotspots that might develop into serious fires.

"At first I was daunted," said Hull, a recent University of Wisconsin-Madison graduate who didn't have much experience building UAVs prior to tackling Logan's project.

But Logan guided his team through the process, showing them how to cut foam parts for the UAV on a CNC hot wire machine. He also taught them to apply composite skins like Kevlar and fiberglass using a vacuum bagging system that molds and seals the composites to the body of the aircraft.

In addition, the students had to optimize the UAV's airflow, install an auto navigation unit, test different motor-propeller combinations, and set up payloads (the aircraft had to carry a video camera and an infrared camera). They even manufactured a camera mount with a 3D printer and a heat sink that was cut using a water jet at NASA Langley's fabrication shop.

"They learned all these things about how you fabricate stuff that they wouldn't have gotten at the university," Logan said.

Vo, a student at California Polytechnic State University, San Luis Obispo, certainly found it enlightening.

"I feel like this hands-on experience will help me become a better designer in the future as I will be able to better understand the feasibility of certain designs and where to compromise between design ideals and ease of manufacturing," he said.

Toward the end of their 10 weeks, Logan's team was ready to send its fire-hunting UAV up for a first test flight, but windy conditions thwarted one attempt and a last-second technical glitch stopped another.

Though the students have since left, Logan is hoping to make another attempt soon. Not only would this UAV potentially save the Great Dismal Swamp money, it could also save taxpayers money. Between the 2011 fire and another fire in 2008, taxpayers had to cover nearly $25 million in firefighting costs. That makes the idea of a UAV that could pinpoint hotspots and lead firefighters to them before they get out of hand that much more appealing.

Logan also sees commercial potential for the aircraft, and had the students design it with that in mind.

"The idea is to make this as easy to produce as possible," he said. "And that was one of the items that I kind of stressed to the students is that hey, every time you have to perform an operation — what the people in the industry call touch labor — every step that you have to make, whether it's turning a screw, whether it's a vacuum bagging process or whatever, that costs money."

Hull, who started the project daunted, but ended it "excited" and "confident," said it was a great experience.

"There are many people out there who do not feel like they are contributing enough with their job and want to make a bigger and better impact on society, and this internship was amazing in that it let us do that," she said. "If our UAV or a UAV inspired by ours is ever used by a park ranger in the Great Dismal Swamp and prevents just one wildfire, it will have my made summer."

Joe Atkinson
NASA Langley Research Center