Increasing operations of military and civilian unmanned aerial systems in shared military, civilian, and special use airspace

Hazards may arise in the following domains:

UAS Design Domain: includes all components, parts, and elements of an unmanned system. This includes the air vehicle, control stations, communication links, and any specialized launch and recovery equipment, and payload.
UAS Flight Crew Domain: includes the capabilities, human factors, and workload of the human pilot of the vehicle and operator of the payload.
UAS Operational Domain: includes the vehicle’s operations within both controlled and uncontrolled airspace, above both populated and unpopulated areas, over either land or water. This includes take off, landing, and any airport operations.

Close-calls and mid-air collision between passenger aircraft and UAS – loss of “see and avoid”

Inadequate coordination between military and civilian UAS in civilian airspace

Inadequate failsafe UAS designs and operations

Unmanned Aircraft loses control link and is not visible to ground based automation/ANSP, Unmanned Aircraft is executing the predetermined flight plan from the point it lost link.

Control link failure between UAS and ground station; equipment failure; intentional takeover

System latency: Time delay in telemetry update or lag in aircraft response to PIC commands or guidance from observer.

Hazards associated with possible use of TCAS for separation assurance given that TCAS was developed as a last resort airborne collision avoidance system: Failure of TCAS traffic display to provide necessary and sufficient information to establish a complete and accurate awareness of the traffic situation in the proximity of the UAS for functions beyond cuing the pilot for increased vigilance in visual acquisition and to prepare the pilot for an impending RA. Information provided on the TCAS traffic display also lacks supplemental information regarding its limitations and inaccuracies for the pilot’s use when formulating traffic situation awareness. TCAS display is subject to large discrepancies between intruder locations as presented on the traffic display versus their true locations. TCAS display lacks the ability to project future states of the intruder. Trajectory information must be estimated by a pilot’s sampling of traffic trends on the display over time. In environments where transponding is not required non-transponding aircraft will not appear on the TCAS display. Information presented on the TCAS traffic display provides inadequate information to establish awareness of the traffic situation. No mitigations could be identified which would reduce the risk of performing a horizontal or vertical maneuver to an acceptable level. Potential for misuse of the TCAS by a remote pilot presents an unacceptable risk. The TCAS system is not an alternate means of compliance, nor is it a means of partial compliance, with 14 CFR 91.111 and 91.113 to see and avoid and to remain well clear of other aircraft.

The State of Nevada research will include a concentrated look at how air traffic control procedures will evolve with the introduction of UAS into the civil environment and how these aircraft will be integrated with NextGen. New York’s research will focus on sense and avoid capabilities for UAS and its sites will aid in researching the complexities of integrating UAS into the congested, northeast airspace.

Safety levels be based on the UAV size, speed, operating environment, mission, or other criteria. The community needs appropriate measures for reliability (i.e., probability of total system failure or by component failure). Given that the vast majority of aviation fatalities today occur to persons onboard an aircraft (as opposed to third party fatalities), it is questionable whether UAVs need to be as safe as manned aircraft given that no onboard lives are at risk. There are however safety issues arising from UAVs dropping from the skies onto persons or property due to inappropriate reliablity levels.