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This is a subject I have been researching (apology for the long post):

Major General Marke Gibson, USAF Director of Operations; the main challenge to UAV NAS operations is widespread misunderstanding about the safety of UAVs. “We’re dealing with a lack of understanding and knowledge about (UAVs). Because they are unmanned, there is a negative connotation that they are out roaming around like ‘machine sharks,’ but, in fact, they are remotely controlled by a qualified pilot who is in control.” Dec 9, 2009, UAV Conference, Tyndall AFB, FL.

UNMANNED AERIAL VEHICLES AND THE NATIONAL AIRSPACE

UAVs historically fly in restricted airspace (test and training ranges) or war zones, and have largely avoided conflict with manned aircraft. This is changing due to increased UAV military testing, training and operational requirements, as well as growing domestic security roles and the emerging role UAVs play in the commercial sector (emergency first-responders, geo-surveys, aerial photography, urban development, etc.). Consequently, it is imperative UAVs be seamlessly and safely integrated into the National Airspace (NAS).

Currently, there are a plethora of agencies and regulatory bodies that are trying to bring order to the chaos of establishing a uniform, international UAV standard. However independent or loosely coordinated these efforts are, their shared goal is to assure UAVs meet the same standards of safety for manned flights and not be burdened with higher levels of performance simply because of enabling technology. Because the most common cause of manned mishaps are mid-air collisions, UAV operations should expect the same and address the challenge of “see-and-avoid.”

“SEE-AND-AVOID” V “SENSE-AND-AVOID”

“The overall objective failure rate for the Predator is on the order of 10-5, a value equal to that for a number of mature manned aircraft.” DOD Unmanned Aerial System Roadmap 2005—2030, Appendix 6—Reliability, Pg H-6

Regardless of the class of airspace (controlled, uncontrolled), or Air Traffic Control (ATC) service, pilots are required to “see-and-avoid other aircraft” whenever weather permits. UAVs should also meet this standard.

Whereas, manned aircraft primarily use visual cues when executing see-and-avoid, the UAV operator uses technical means to “see” (sense). Regardless of the mode (sight or technology), pilots and UAV operators will “sense” to avoid potential conflicts. Whatever means used, they both sense-and-avoid (S&A) and therefore can meet “see-and-avoid” regulatory requirements.

Although S&A capabilities are not quantifiably defined, certain documents help circumscribe the requirements for such a capability. However, within those documents a bias regarding UAV S&A emerges, with “see-and-avoid” as the primary obstacle to integration and acceptance of UAV operations in the NAS. Essentially, the bias appears to overburden UAV operations with onerous levels of safety far beyond manned flight thresholds. In the United States, this issue was addressed early through an FAA White Paper, Sense-and-Avoid Requirement for Remotely Operated Aircraft, June 2004. The White Paper suggested UAV sensing technologies may actually eventually reduce air-to-air mishaps because technology is not influenced by external distractions, attention lapses or emotional overlays. Therefore, S&A technology can reasonably be expected to evolve to meet (or exceed) manned safety standards. The challenge then is to collate and synthesize the research to prove the concept beyond anecdotal research results. Of course, once proved, UAV S&A safety performance needs to be continually researched and analyzed to detect trends and identify cross-functional technologies that may enhance manned flight capabilities. Nonetheless, it is clear UAV technology and operations are in some cases achieving safety rates equal to manned systems.

There are many formulas establishing a benchmark level of a safe UAV S&A capability, but there is no uniform standard, because if there were, there would be one formula recognized as the objective safety score. To establish a standard without solid grounding in meaningful data will result in bad policy that either establishes an unreasonably high S&A standard or establishes an unsafe lower standard. Simply put, uniform, verified data is desperately needed to ensure reasonable UAV safety regulation. This regulation, internationally recognized, should require UAVs have onboard a self-contained ability to detect traffic conflicts, independently determine right-of-way, predictably maneuver well clear, and yield if the other platform does not adhere to avoidance responsibilities.

The introduction of UAVs into the NAS is challenging. Government, civil, industry and military UAV proponents are eager partners in developing and implementing operationally sound UAV practices. That said, close coordination with the US is in order to leverage their UAV advances. With mature S&A technology, coupled with professional certification standards for UAV operators, UAVs can operate safely in the NAS at a safety rate that is equal to, or better than, manned aircraft. Therefore, it is recommended efforts focus on forming a central technology development “center-of-excellence” that would function as an accrediting focal for collating S&A research and development findings, issuing reports and recommending reasonable UAV regulatory standards based on hard data.