ROBOTICS AND AUTONOMOUS SYSTEMS
Flying Drones in U.S. Airspace Not as Easy as It Looks
The military makes it look like a videogame. Pilots sit in front of a bank of computer monitors, press buttons and push joysticks to guide the drones.
If the military can do it so well in war zones, how hard can it be to fly unmanned aircraft in U.S. airspace?
Apparently not as simple as it might appear, unmanned aviation experts say. Although drones are now more technologically advanced and, theoretically, safer than they’ve ever been to operate in congested airspace, more research and tests are needed before they should be allowed to populate the skies, these experts note.
A highly anticipated unmanned aviation boom hangs on future decisions by the Federal Aviation Administration. The agency faces a 2015 congressionally mandated deadline to lay out a plan for integrating unmanned aircraft into the national airspace.
Retired Air Force Maj. Gen. James O. Poss says he is often asked why the government needs so much time and effort to test the safety of drones that the military has been flying for years. “Why don't we just transfer those same rules to the national airspace?” Poss asks during a recent Mississippi State University webinar.
Poss, a former assistant deputy chief of staff for intelligence, surveillance and reconnaissance, oversees an MSU-led consortium of 13 universities that is seeking to become anFAA unmanned air systems, or UAS, center of academic excellence and one of six yet-to-be-selected test sites.
Creating a domestic regulatory environment and infrastructure for the safe operation of unmanned aircraft is far more difficult than anything the military has done, Poss says.
The biggest difference is the anticipated size and scale of civilian UAS operations, he explains. “The military flies hundreds of unmanned air systems in restricted airspace, largely in water zones.”
When FAA integrates UAS into the national airspace, “You will probably see thousands of UAS flying daily,” he adds. “When you talk about that much airspace being made available for unmanned systems, that is a topic that is well worth researching.”
Even though drones have become increasingly mainstream, there is still some discomfort with the idea that an aircraft has no pilot onboard, officials have said. That is the reason the U.S. Air Force prefers to call its drones “remotely piloted” aircraft.
Part of the FAA’s challenge, Poss says, is to decide how much “autonomy” should be allowed in UAS, versus giving more control to the human operator on the ground. “No matter how you slice it, you will either need an ultra reliable data link to uplink commands to the aircraft, or you will need some degree of autonomy and let the aircraft maneuver itself,” Poss says. “Both have all kinds of safety concerns that we need to take a hard look at.”
Another potential headache for the FAA in crafting regulations is the overwhelming breadth of the unmanned aircraft market. They range from hummingbird-size to as large as a small jetliner. “Once you're freed from the need to put a pilot in the aircraft, you can make them just about any size,” says Poss. Aircraft will be made from all types of materials. And there is no standard means of propulsion. “With no size limit you can put an electric engine more easily than you could in a manned aircraft,” he says. UAS can be powered by many types of fuel, from hydrogen to diesel to electric batteries. “They all pose a challenge to the FAA in certifying the airframe as airworthy.”
Complicating FAA’s job is that there are no existing rules for UAS air vehicle certification, says Poss. And there will be lots of new technologies that commercial UAS vendors are going to want to try out. Boeing’s Phantom Eye unmanned aircraft is powered by hydrogen and can stay in the air for a week. “We've never used hydrogen with manned aircraft,” Poss says. New rules will have to be written, for instance, for how to certify electric engines. “I can't think of a manned aircraft that has an electric motor.”
Poss says the FAA also will need to further research how pilots perform on the ground. “Ground based cockpits can present a challenge,” he says. “They have the potential to get terabytes of information into a ground based cockpit that you can't put into a cockpit that is flying.” Avalanches of data, says Poss, could “overwhelm the ground-based aircrew.” Civilian UAS operations will cover many different mission profiles, each with its own safety considerations, he says. “We'll have to reinvent human systems integration to put the cockpit on the ground.”
Mike Corcoran, UAS course manager at the University of North Dakota, says he is seeing significant progress in technologies that will make drones safe to fly. A central requirement will be for UAS to have “sense and avoid” systems to avert mid-air collisions. Recent tests show the technology is improving, he says, although “flying in busy areas is where a lot of the risk can take place.”
Concerns about UAS’ ability to sense other objects is the reason the FAA limits the use of commercial drones, he adds. “There are procedures for flying unmanned aircraft in U.S. airspace but they are fairly restrictive.”
The FAA worries about aircraft’s “situational awareness,” says Mark Blanks, UAS program manager at Kansas State University. UAS have no view out of the window and limited sensory feedback, he says. “We can't hear the engine having trouble. Or smell something burning.”
Kansas State is one of a handful of schools that offers bachelor's degrees in UAS operations. Education is a “major challenge,” says Blanks. With a wide variety and configuration of aircraft, training on one family might not translate well to other aircraft. “There has to be more standardization of systems and education,” he says. There are yet no federally accepted educational certifications. “It’s somewhat of a guessing game what those requirements will be down the road.”
The first FAA-approved commercial UAS flights took place last month in Alaska. These flights are helping engineers and researchers figure out the way ahead, says Gregory W. Walker, director of the
Alaska center for UAS integration at the University of Alaska Fairbanks. “We are taking baby steps,” he says. ConocoPhillips operated an Insitu Scan Eagle UAS over the Chukchi Sea in northern
Alaska. One test was successful. The second ended in a crash. “The flying was all over water, in a very defined, manageable airspace,” Walker says.
The FAA so far has certificated the Scan Eagle and the AeroVironment Puma for commercial operations in the United States. “There is a lot to be done before they fly in urban areas,” says Walker. “And a lot of questions to be answered.”