August 1, 2011  

New territory

Integrating unmanned aircraft into civil airspace must address safety

The huge increase in unmanned aircraft use — most apparent in the Iraq and Afghanistan wars — makes it easy to assume that unmanned will soon be the norm. The next new long-range bomber potentially could be unmanned.

A high hurdle stands in the way of that potential, however. Unless and until the services, government agencies and industry can work out how to acceptably integrate unmanned aircraft with conventional commercial airplanes in an already crowded national airspace, unmanned aircraft will be niche players largely restricted to operations where airspace is wide open and under military control.

The U.S. National Airspace System (NAS) is neither wide open nor under military jurisdiction. Yet pressure is increasing for a solution that would help blend the operations of airliners, general aviation aircraft and unmanned aircraft. The Defense Department needs more U.S. airspace for training exercises involving its growing unmanned fleet. Law enforcement, homeland security and border patrol agencies, and natural disaster relief organizations (such as wildfire fighters) are relying more on unmanned aircraft and need to be able to operate them side by side with conventional aircraft over the U.S.

Under current rules, for unmanned aircraft to gain access to the civil airspace, a Federal Aviation Administration (FAA) Certificate of Waiver or Authorization (COA) must first be granted. These case-by-case COAs take time to process and may come with restrictions that inhibit use of unmanned aircraft. For example, a manned “chase” aircraft may be required to shadow the unmanned craft and be its “eyes.” Understandably, DoD and other unmanned aircraft operators want more freedom to conduct routine operations without getting bogged down in paperwork and red tape.

On the other side, and in control of the NAS, is the FAA. While the Pentagon is a mission-first organization that accepts certain risks; the FAA is a safety-first agency. Friction is inevitable, given the two different mission-sets and cultures. Milestones for providing expanded access to the NAS for unmanned aircraft have been set under the DoD’s UAS Transition Plan, which calls for certain unmanned aircraft-accessible sites to be activated by 2015. FAA is pushing for the completion date to be postponed until 2020.

FAA’s concerns are not easily dismissed. The NAS is a massively complex environment that encompasses an average of more than 100,000 aviation operations per day. On top of that, more than 238,000 general aviation aircraft may enter the system at any time. Maintaining safe separations among them all requires strict adherence to rules and regulations, the top three of which are FAA foundational requirements. For any aircraft to fly routinely in the NAS, it must first be certified as airworthy, the pilot in command must be qualified in the appropriate classes of airspace, and the flight operations must comply with applicable regulatory guidance.

FAA — which is, after all, a regulatory authority — is rigid on applying the same rules to unmanned flight operations as apply to commercial aircraft, even when those rules are not necessarily applicable to modern-day civil flights. But FAA raises valid reasons for proceeding cautiously. It insists that more safety data is needed before it can make an informed decision on unmanned aircraft integration. The data it does have, though insufficient to be statistically representative, is not encouraging. For example, Customs and Border Patrol unmanned aircraft data show an accident rate of 52.7 accidents per 100,000 flight hours for the period between 2006 and 2010. That’s more than seven times the general aviation rate and an eyebrow-raising 353 times the commercial aviation rate.

FAA also does not have sufficient data on the type of damage that would be sustained in a collision involving unmanned aircraft. It needs that, just as it has accumulated detailed data on the impact of birds on aircraft. So if DoD wants to fast-track the integration process, it must also speed up data collection. Unmanned aircraft manufacturers could play a key role here, just as the commercial airframe and engine manufacturers have been instrumental in obtaining bird-strike data.

Even so, as Andrew Zogg, vice president at Raytheon Network Centric Systems command and control systems, points out, “This is not Big Bang theory.” The backbone to successful integration, he says, will be automated command and control. What’s needed is a holistic approach that looks outside the conventional air traffic control system and in which the coordination of airspace becomes more generic. Central to that will be a secure but information-shareable architecture that lets all the players safely come in and out as they need.

The push-pull of unmanned aircraft versus commercial aviation needs will continue. Ultimately, however, the onus is on unmanned aircraft providers and operators to demonstrate safety standards to FAA’s satisfaction. Just one incident — an unmanned vehicle colliding with an airliner with 300 passengers onboard — would potentially be the death knell of unmanned aircraft/NAS integration. AFJ