Andrew Zeitlin, The MITRE Corporation
Andrew Lacher, The MITRE Corporation
James Kuchar, MIT Lincoln Laboratory
Ann Drumm, MIT Lincoln Laboratory
Applications for Unmanned Aircraft Systems (UAS) abound from military and homeland
security to commercial services. The ability to integrate unmanned and manned aircraft
into the same civil airspace is a critical capability that will enable growth in the industry,
expansion of applications, and greater utility for UAS operators.
Collision avoidance is emerging as a key enabler to UAS civil airspace access as well an
important capability for the integration of manned and unmanned missions in military
theaters of operation. UAS collision avoidance capabilities must be interoperable and
compatible with existing collision avoidance and separation assurance capabilities
including the Traffic Alert and Collision Avoidance System (TCAS) and the requirement
for a pilot to see and avoid other aircraft consistent with the right of way rules.
The operational and technical challenges of UAS collision avoidance are further
complicated by the wide variety of unmanned aircraft, their associated missions, and their
ground control capabilities. Numerous technology solutions for collision avoidance are
being explored in the community, including research sponsored by the National
Aeronautics and Space Administration, the United States Air Force, The Defense
Advanced Research Project Agency, and others. The Federal Aviation Administration
(FAA) has requested that RTCA, Inc. develop Minimum Aviation System Performance
Standards (MASPS) for UAS collision avoidance, referred to as UAS Sense and Avoid.
While the technology research activities are important to the development of these
standards, analysis will be required to ensure that the technical solutions provide a
satisfactory level of safety. The intent of this paper is to present one perspective on the
system safety studies necessary for the community to reach consensus on the appropriate
standards—a necessary step so that a collision avoidance capability for unmanned
aircraft can be certified by the FAA.
The MITRE Corporation and Lincoln Laboratory have collaborated on this paper because
we believe that it is important to articulate the system safety studies needed. Our two
organizations bring a wealth of knowledge and experience associated with the
development and implementation of TCAS. We were directly involved and/or closely
associated with a significant portion of the system safety analysis that supported RTCA,
FAA, Eurocontrol, and International Civil Aviation Organization (ICAO) decisions
related to TCAS2 standards and certification.
