Invasion of the Drones

Pilotless aircraft have shown their worth in battle, but integrating them safely into domestic airspace presents many challenges.

Global Hawk Drone

Global Hawk Drone

Global Hawk Drone

Are you concerned about the sky gradually becoming filled with windowless aircraft controlled by someone miles (maybe even states) away? You’re not alone. But it may be that the real “threat” turns out to be less about midair collisions and more about increasingly complicated and restricted airspace rules to accommodate remotely piloted aircraft operations.

They are variously known as the unmanned aerial system (UAS), the term favored by the manufacturers; unmanned aerial vehicles (UAVs); and, most popularly, “drones.” Whatever the name, the science of unmanned aircraft has changed forever due to modern satellite navigation and optical technology, and still bigger changes are just over the horizon. Some of them are technological; others are sociopolitical in nature. Just how big the changes will be, and how far over the horizon they are lurking, is causing controversy within aviation circles, and even more attention from those concerned over privacy rights.

There are three primary attributes to unmanned systems compared with piloted aircraft (aside from not having to pay crew salaries and benefit packages). First, an unmanned aircraft is not limited by the sensitivity to G-forces of the human pilot. Admittedly, this is mostly a concern for combat aircraft. Second, unmanned aircraft can complete missions that would be too risky for human-powered aircraft (this could involve combat, but also police pursuit of suspects, search and rescue in bad weather, firefighting and inspection of hazardous-materials spills or nuclear meltdowns, for example). And finally, there are some missions that are just so simplistic and repetitive that even the most astute human would eventually become too bored to be able to remain effective (think long-term border patrol or a police stakeout, for example). Some drone platforms that are perfectly suited for these missions are capable of remaining aloft for days at a time. The physiological limitations of a human crew (sleep, food, etc.) would not permit full use of the aircraft’s capabilities. The extra 200 pounds (or more) of fuel or payload doesn’t hurt, either.

The Association of Unmanned Vehicle Systems International (AUVSI), the largest drone industry trade group, predicts as many as 30,000 drones will be flying in U.S. airspace by 2020 (that would compare with approximately 231,000 currently registered "manned" aircraft, of which 223,000 are members of the general aviation fleet). This year's FAA funding bill, the first long-term bill to pass muster since 2003, includes a mandate to "fully integrate" drones into U.S. airspace by the end of September 2015.

The association is quick to reassure pilots that a large percentage of the 30,000 aircraft will be small, low-flying drones — similar to radio-controlled models — that it says will not significantly affect manned operations. A midair collision with even a 4.4-pound “Group One” UAS (there are five official groups based on size, altitude capability and speed) would likely cause you to crash, and so the certification process of these lower-end types requires line-of-sight observation by FAA-licensed operators or a licensed observer, and it limits altitudes so as not to interfere with manned aircraft.

Drones that will operate in general airspace are another story, and some could be airliner-size. But they will not do so unannounced, according to AUVSI. They will operate under ATC surveillance (including transponders and two-way radio link) and have on-board sensing equipment to help avoid manned aircraft. That technology is still developing. Each operation will be preceded by a notam alerting pilots of manned aircraft when the drone will be flying and its planned route. That’s a little less scary from the collision point of view, but perhaps disconcerting when it comes to further limiting airspace access and complicating the flight planning process for us pilots.

The legislation’s integration timetable starts with the FAA, which is the controlling agency for all UAS operations in the national airspace system (NAS). The agency has been tasked with establishing six drone testing sites across the nation by the end of this year. It wasn’t a good sign that the agency missed its Aug. 12 deadline for initially proposing these sites. By February, a five-year “road map” from 800 Independence Ave. is due before Congress detailing exactly how the agency plans to integrate the unmanned aircraft. The final rule is due in August 2014, with the first permits for operating civil drones expected to be awarded starting in early 2015.

It's a daunting schedule that already has experienced its first speed bump, and skeptics doubt there's enough time to make it all happen safely, especially considering the slow pace of implementing the Next Generation Air Transportation System, the ongoing overhaul of air traffic control. NextGen includes much of the infrastructure technology drones will ultimately depend on for their "sense and avoid" technology — the equipment enabling them to share airspace safely with other aircraft. AUVSI President Michael Toscano serves on the NextGen Institute Management Council, a board of 17 aviation industry leaders advising on the implementation of the ongoing infrastructure revamp. He said, "NextGen will be required to safely integrate routine operation of UAS with manned platforms."

Even with the eventual promise of NextGen’s efficiencies, the specter of 30,000 unmanned aircraft, ranging in size from hand-launched mini drones to airliners, being flown from armchairs and computer consoles has human pilots concerned, to say the least.

Heidi Williams, vice president of air traffic control services and modernization for the Aircraft Owners and Pilots Association, said the group generally supports the development of UAS but takes a “wait and see” attitude toward full integration. She said there is “a lot to be done” and that full integration “may be difficult.” She also said the definition of “full integration” is not crystal-clear and that the FAA will likely follow a phased approach that could be flexible along the way. Williams said: “AOPA is involved with all the rulemaking committees on UAS, and we’re working closely with the FAA’s UAS integration office. Our position is that, naturally, the top priority has to be safety. ‘Do no harm’ to the national airspace system is the first rule. Beyond that, the burden of proving the airworthiness of the systems is on the manufacturers.”

Steve Brown, chief operating officer at the National Business Aviation Association, spent seven years at the FAA as vice president of operations and planning and associate administrator for air traffic services. He said: “NBAA certainly supports the integration of UAS for the valuable roles they can serve in search and rescue, some agricultural operations, security and others. We feel the timeline is … ambitious. It’s more important to protect the timelines of the research, which doesn’t necessarily always line up with the [schedule defined in the] statement of policy.”

Brown, who sits on several of the FAA research committees on UAS integration, echoed Williams from AOPA in emphasizing the importance of safety in the integration process. He also said the integration needs to be incremental: “That way you not only develop the technology as you go, but you also build confidence among the stakeholders that the systems work and are reliable.”

Though full-scale implementation of the policy is still a few years away, partial approvals are coming even sooner for qualified first-responder agencies. For example, some agencies will be permitted to fly drones weighing 4.4 pounds or less, starting about the time you read this. Within the next 12 months, drones weighing less than 55 pounds will be permitted to fly in the Arctic region of the United States 24 hours a day at altitudes of 2,000 feet or less. And by mid-2014, 55-pound drones are scheduled to be allowed to fly within the entire U.S. airspace system with appropriate certificates of authorization.

There are three elements to a UAS certification process, and the details are currently being evaluated by several committees as part of the FAA research with input from the industry, AOPA, NBAA and other stakeholders: The aircraft and guidance systems themselves must meet airworthiness standards; the operator and/or observer must be appropriately trained and rated; and the specifics of each individual operation must be approved. Whether it’s a one-time authorization to fly a 4.4-pound surveillance rotorcraft 400 feet above a hostage situation or a long-term approval to monitor polar bears with regular flights within a specified block of Arctic airspace, each mission would be approved by the FAA and the appropriate notifications posted for pilots of manned aircraft.

Privacy Concerns
Pilots are concerned about unmanned traffic up there, for sure, whether it's about safety or further airspace restrictions. But politically, we're small potatoes. In contrast, roughly 99.8 percent of the general public's worry over unmanned aircraft is focused on privacy issues. Unlike the 0.2 percent of the population that are active pilots, most other Americans appear far more troubled by the prospect of high-definition video cameras spying on them from thin air than they are by the risk of a midair collision, even if the debris might land on their house.

As a society we’re still acclimating to traffic cams snapping images of our license plates if we run a red light at 3 a.m., or ATM cams catching us picking our noses while we’re waiting for our cash. But at least, so far, surveillance cameras have been ground-based and mostly perched at predictable vantage points. On-demand airborne video surveillance is something else again.

Drone Makers Unite
For its part, the AUVSI has addressed the issues of safety and privacy on behalf of its industry. Toscano said, "AUVSI has met with nearly a dozen privacy advocates and civil liberties organizations, as well as other interested parties, to understand their concerns, encourage them to work together and let them know that, like them, AUVSI supports Americans' rights to privacy, especially the protections afforded under the Fourth Amendment to the U.S. Constitution. Meanwhile, the industry's recently released code of conduct clearly articulates a commitment to respecting individuals' privacy. As the integration progresses, the industry will continue to engage in constructive, thoughtful and civil dialogue on the national, state and local levels with all parties to address any privacy concerns."

On the issue of safe, prudent operation of drones in general-use airspace, Toscano said the industry is making every effort to coordinate with FAA certification efforts that would minimize risk to an “acceptable” level. That includes vetting the airworthiness of the aircraft (and, even more important, their radio control systems); operator training and certification; and taking a cautious approach to procedures. He said risk of collision depends greatly on the situation, citing the example of a police department launching a small drone to monitor a hostage situation (flying no higher than 400 feet in line of sight with its operator). In contrast, a high-flying surveillance drone would have to penetrate at least a “band” of airspace where manned aircraft fly. In that case, he said, there would be detailed notams issued through Flight Service, and ATC would monitor the drone flight just as it does a manned aircraft, except the voice radio link would be with the operator on the ground.

Toscano added that the approval process involves a detailed review of the traffic history in any airspace where drones might operate.

“As an example,” he said, “let’s say a government agency wanted to patrol a 100-square-mile area of the Arctic to observe polar bears. The FAA would look back at the past several months and see that only one manned aircraft had flown into that airspace. The risk of a conflict would be extremely low.”

Acknowledging that the consequences of any conflict would be dire, regardless of how low the risk, Toscano added that there would be ample warning issued to pilots that the patrol flights were taking place. Even in the hypothetical case of a floatplane pilot without a transponder who did not get the notam and decided to visit a fishing spot he hadn’t flown to for years, all would not be left to chance. Ground-based elements of the “sense and avoid” technology (apparently a play on the familiar words see and avoid) could be placed to help ensure that a drone would avoid colliding with a manned aircraft.

Toscano cited a recent two-week Army evaluation of its Ground Based Sense and Avoid (GBSAA) system at the Dugway Proving Ground in Utah. Using sophisticated, military-grade 3-D radar and software algorithms, GBSAA is designed to detect other aircraft — even a non-transponder-equipped wooden homebuilt — flying near the drones and to steer the unmanned aircraft safely away. Toscano said the tests were successful.

“We can’t reduce the risk to zero — no one can — but our goal is to bring the risk level down to an acceptable level when compared with the benefit that operating these vehicles can bring,” he said.

He sees the implementation of ADS-B technology as an avenue to more fully integrate drones into shared airspace in the future. Although a particular mission might require restricting airspace in the pre-ADS-B world, it is hoped that after ADS-B is fully implemented, drones might be able to operate safely in closer quarters with manned aircraft. In other words, the collision protection provided by ADS-B for manned aircraft would extend to include unmanned aircraft as well, at least to a degree.

FAA on Board
On Aug. 7, acting FAA Administrator Michael Huerta addressed the AUVSI's convention in Las Vegas, assuring the industry that the agency is preparing to "realign" itself to accommodate drones.

“We need to change the way we do business,” he said. With the civil drone industry expected to become a multi-billion-dollar concern, Huerta told its leaders, “we are going to allow new ideas to soar to their potential. Our goal is to safely and efficiently integrate unmanned systems into our airspace. Building new technology is one thing, but building human consensus on a path forward for our aviation systems is an equally important task and unbelievably complicated. There’s a lot of work that has to be done, but I am very optimistic that we’ll get there.”

So where is the critical mass coming from that is driving the FAA to embrace unmanned aircraft? It has to start with the stunning success of drones in combat, and the industry that has grown up around that advancing technology. We’re all familiar with how unmanned surveillance and attack aircraft have impacted the wars in Iraq and Afghanistan. As the role of drones has expanded in combat, the level of sophistication in their guidance systems and surveillance capabilities has ramped up. With those advances in technology, the manufacturers have expanded their market focus to the civilian sector.

Drones Already Crashing
There have been some confidence-busting problems with military systems, however, including the crash of a Navy drone onto Bloodsworth Island off the Eastern Shore of Maryland in Chesapeake Bay. The Patuxent River-based RQ-4A drone was no hand-launched glorified RC model, either. A derivative of the Air Force Global Hawk, the RQ-4A is 44 feet long with a wingspan of 117 feet. It is capable of flying at least as high as 50,000 feet. The one that crashed was part of the Navy's Broad Area Maritime Surveillance (BAMS) program, and it's been stingy with information about the accident. There were no injuries on the ground, nor any property damage, despite the fact that the burning wreckage covered an area the size of a football field.

Significantly, Bloodsworth Island is owned by the Navy, and no one lives there. It was used as a practice strafing target range starting in 1948 and up until the mid-1990s, so it’s possible the aircraft was directed there when it encountered problems. Capt. James Hoke, program manager for the Navy’s Persistent Maritime Unmanned Aircraft System Program office, said the drone was an older ex-Air Force Block 10 model. He said the type has had “reliability problems” but declined to go into the specifics of the failure, other than to say the problem was mechanical and was airframe-related.

Last December, an RQ-170 Sentinel stealth surveillance drone went down in Iran, 140 miles from its base. The United States claims the Lockheed Martin-built drone, operated by the Air Force for the Central Intelligence Agency, malfunctioned and its operators lost control of the craft. But Iran takes credit for busting the aircraft’s encryption code and bringing it down mostly intact, under its control. To date, there is no confirmation of either side’s version of the events. Earlier this year, Iran displayed a copy of the drone it says it has developed from the captured aircraft.

So-called “spoofing” of GPS signals has been a hot topic since the early 1990s, related not just to drones but also to any activity relying on GPS. The relatively weak signals are vulnerable to hackers who can override the satellite transmissions with false ones, making the onboard GPS receiver “think” it is somewhere it isn’t — and direct an unmanned vehicle accordingly. Military drones, including the RQ-170 Sentinel, have heavily encrypted GPS and control receivers designed to thwart spoofing, but BAE Systems has come up with yet another backup plan, which could be incorporated into civilian drones to ensure they are not “hijacked.”

It’s called Navigation via Signals of Opportunity (NAVSOP), and some argue it could even replace GPS. NAVSOP eavesdrops and collates existing transmissions such as Wi-Fi, television, radio and cell phone signals to triangulate the receiver’s position, reportedly to within a few meters. According to BAE, “Even the signals from the GPS jammers can be exploited by the device to aid navigation under certain conditions.”

These two incidents have done little to reassure skeptics of the so-called “loss of control” technology that is proposed for certifying UAS operating in U.S. national airspace system. Should radio control be interrupted, the UAS is programmed to immediately squawk a dedicated transponder code so ATC will be instantly aware of the situation. It will also trigger onboard navigation computers to steer a predetermined course to safe, uninhabited airspace. Meanwhile, forward- and side-looking sensors are designed to detect any “targets” that are not visible to controllers, or that otherwise fall through the cracks. The technology is based on the most advanced military guidance and control equipment, and manufacturers contend that the technology is continually developing. Still, the lack of a human pilot – who could react and improvise outside the black box – has critics skeptical that they could feel secure sharing airspace with drones.

From the rush of activity emanating from Capitol Hill, FAA headquarters and the industry, it is clear there is a strong push to mandate integration of unmanned aircraft into our airspace on an ambitious schedule. The industry group appears committed to doing what it can to ensure the safety and moral integrity of the process. Admitting that he is one himself, Toscano said, “Bureaucrats are like witches. There are good ones, and there are bad ones.” Between now and the deadline for full implementation in about three years, pilots will be watching closely to judge which category he fits, and whether or not they trust the technology to safely separate our aircraft — the ones with windows — from those without.

What remains to be seen is whether the politics can keep up with the technology as it exists today, and whether the NextGen technology of tomorrow will arrive in time to safely separate our aircraft — the ones with windows — from those without.