Perhaps even more ambitious is a NOAA project employing UAVs as hurricane hunters. In 2007, a craft developed by Aerosonde flew into the eye of Hurricane Noel as the fast-growing storm approached the East Coast. The NOAA craft loitered inside the hurricane for nearly eight hours, flying below a height of 325 feet as it measured winds and air temperature. That’s far lower than manned hurricane-watching aircraft such as NOAA’s four-engine P-3 Orion would dare go.
“It’s really useful to take an unmanned aircraft to those lower elevations, as the risk of catastrophe [with a manned aircraft] is just too high,” says Marty Ralph, a research scientist with NOAA’s Earth System Research Laboratory. Costs also are much lower with UAVs, he says, so more projects can be pursued.
Because of the sheer versatility of UAVs, their missions are for the most part limited only by imagination. A case in point: In April 2008, NOAA experimented with a UAV built by Airborne Technologies, based in a town that by November 2008 everybody had heard of: Wasilla, Alaska. The aircraft, called the Resolution, was used in the north Pacific to hunt for ghost nets—drift nets that have escaped from fishing vessels and then float with the current, devastating marine life. (By some estimates, ghost nets in the north Pacific alone cause thousands of birds and marine mammals, such as porpoises and seals, to drown each year.)
The Resolution is equipped with video sensors that can detect anomalies in the water; GPS sensors automatically mark the location of nets it finds, for recovery by boats. While the Resolution takes off and lands with the help of a shipboard pilot, it flies its route autonomously.
Autonomous flight is what really gets UAV supporters enthusiastic. Such aircraft could hunt for forest fires, for instance—or, more usefully (since finding a forest fire is rarely difficult), fly the night missions fire managers rely on to map the size and intensity of a blaze through infrared sensors. For his research on plant pathology, David Schmale could use multiple autonomous UAVs to find and track plumes of airborne pathogens, measuring the plumes’ size, direction of drift, speed, and more. In the event of a terrorist attack, such UAVs could track airborne chemicals or biological agents.
And in Utah, where state laws require highway patrol officers to photograph injury accidents, troopers are interested in carrying UAV helicopters in the trunks of their patrol cars. At an accident scene, a trooper could punch in some GPS coordinates and the little helo would take off, buzz over the specified grid, take pictures, and land.
For the most part, the machines are here today. The big challenge, says Jonathan How, a professor at the Massachusetts Institute of Technology, is designing an airspace they can fly in. “All GPS tells an aircraft is where it is,” says How, who designs autonomy software for UAVs. “Flying safely also requires [knowing] what else is out there.” Achieving that will require communication between aircraft, or visual sensors on the aircraft, or data sent from ground stations.
“I understand what they want to do—I heard a DOJ [Department of Justice] guy talking about the Utah proposal,” says Kenneth “Doug” Davis, a longtime FAA official who now is running the agency’s program on managing UAVs in the national airspace. “But there are 19,000 law enforcement agencies in the United States. Of those, fewer than 300 have aviation units. So less than two percent of these guys have a clue about what constitutes ‘airworthiness.’ ” In terms of teaching potential UAV operators the rules of aviation, he says, “we have a big education gap to fill.”
Davis points out that today’s UAVs—which can resemble everything from an insect to a small piloted aircraft in size—simply don’t fly the way other types of aircraft do. “An airliner operating at 30,000 feet can move 500 knots across the ground,” he says. A UAV “might have the thrust to reach 30,000, but then it’s moving at only 100 knots. That creates a big challenge for integrating slower aircraft into the airspace.”
The FAA issued 165 Certificates of Airworthiness for UAVs in 2008, up from 85 in 2007. The agency, which hopes to pick up the pace, is working on new regulations and plans to start gathering public comment late this year and into 2010.