CON 2: Contingency Initiation

The CON 2 test had test sites coordinate a planned emergency that necessitated activating a prepared contingency plan. Options included an incursion of one vehicle into the volume of another, or an “event” that required a vehicle to make an emergency landing. Two of the three test sites chose to have one vehicle breach the volume of another. The third test site set up an “event” where their vehicle had to land in place. Survey questions asked about users’ situation awareness during these maneuvers, their decision making and their reactions to their contingency plans, while debrief prompts focused on situation awareness, information that is useful, and risk assessment (Table 14). The contingency scenarios demonstrated in CON 2 also relate to other tests from TCL3, such as the general goal of the Sense and Avoid RTT to investigate conflict mitigations, and

specifically the off-nominal conditions tested in SAA 5. From the UTM concept perspective, NASA is able to specify use cases that illuminate whether the current infrastructure and capabilities meet the needs of the user.

5.5.1 Information Desired

Participants listed many items of information that they would like to have when there is a vehicle in their vicinity that is having a contingency event. These items included being told the location of the vehicle in trouble, also its position, altitude, heading, velocity, flight trend, position history trail, and aircraft type. Other desired information was whether the vehicle was hovering, how far it was from their ownship, and whether it was in compliance. Some crews said they wanted information about every vehicle within a set radius of their ownship. However, an item of information that crews were clear they did not need to know was the nature of the emergency that the other vehicle was having. Crews talked about the way this information could be represented on a display, noting that symbols, colors and icons are better than text for conveying information under time-critical circumstances.

Table 14. CON 2: Discussion Topics and their Notional Categorization into Information Themes

Information Category Site 1 Site 5 Site 6

Information property 2 6

Information meets user 5 9

Operator status 2 2

Methods 5

Automation Concept

5.5.2 Operator Experience: Situation Awareness

Participants were asked about their situation awareness while the contingency event was occurring and how effectively the alerting drew their attention to the event (Figure 17). Half of the respondents obtained information about the event from another team member, and the other half obtained their information through tools, although only one used the USS client for this (n = 7). Crews estimated that their SA, both for their operations and for the surrounding airspace, was “very high” (𝑥 = 6.7) but they reported that the USS alerting was only “somewhat” effective at alerting the emergency (𝑥 = 4) and was “a little” useful (𝑥 = 3). For the alerting questions, the standard deviation for Test Site 5 is large, indicating that participants did not agree on the usefulness and effectiveness of the USS client’s alerting. Participants discussed that alerting is an important function during a contingency event and that a key item of information to share with others is the status of a vehicle, especially if rogue or out of conformance. If the USS client provider knows this information, they can take steps to broadcast that, and a wide alert lets others know there is an event occurring. The on-site NASA representative noted that at one site, the test notifications for the contingency event would be so frequent, and persist for so long, that the primary function of the display was obscured during critical phases of the flight. Alerting is important for operator situation awareness, but consideration should also be given for the primary task of aviating safely.

Figure 17. Operator awareness during CON 2 testing in TCL3 for Test Site 5 (n = 5). Note: Rating scale was 1–7; y-axis is longer to show SD.

Where participants found the USS client displays useful was in giving them a “birds eye” view of the activities going on in the airspace, so that they had an idea of how busy the airspace was even though they could not see it from their GCS. A second benefit was that, while the UTM tools are still in development, traffic displays give reassurance that the UTM tools are working properly. Crews at one test site liked the SA that the USS client gave them because it meant they were able to deconflict flights in real time.

5.5.3 Operator Experience: Decision Making

During the event, vehicles at Test Site 5 had the option to RTB, loiter or ascend/descend to resolve the situation. Crews reported they were “quite confident” (𝑥 = 5.2) that their contingency plans were the best response options to the event and thought they were “quite appropriate” (𝑥 = 5.2). They had

0 1 2 3 4 5 6 7 8 SA for your

operation SA for surroundingairspace Usefulness of alert Effectiveness ofalert to emergency

Me an S A ra tin g

Operator awareness elements (Test Site 5) Very

high

Very low

no safety concerns during the flight tests. However, they estimated that they had “slightly less” time to react to the event than they had expected (𝑥 = 3.4). Despite crews reporting they were only

“moderately confident” (𝑥 = 4.4) that their vehicle was behaving as they expected, crews reported in their surveys that they were not having any issues, e.g., “My aircraft was reacting as I controlled it. At no point did I feel that I had a loss or degradation of control.” Crews reported that they were “moderately” confident that their USS client (𝑥 = 3.75) was behaving the way they had expected, although few people could see the display and so only these (few) people actually had the

opportunity to see the messages that were sent through UTM.

Respondents varied in the amount of information they felt they needed to make decisions during contingency events. Some reported they just needed to make sure the airspace they wanted to operate in was clear of hazards and safe.

5.5.4 Operator Experience: Actions

Crews were divided over the best way to handle contingency procedures and alerting in UTM. The majority (4) thought that shared ability between manual and automated responses was the best solution, but others preferred fully manual or fully automated responses. Those arguing for fully manual responses did so because every contingency event is unique and needs a specific response. Those arguing for fully automated responses noted that the PIC will be too busy to send messages to other crews and local entities during an emergency situation.

Supporting the comments of those who said contingency events are unique, debriefs explored that crews were creative in the ways they reacted to events. One crew, who was operating the vehicle with the emergency, designed an RTB route and then built a TFR around it, essentially putting a volume around their vehicle for the RTB transit. They discussed the advantages of doing this; flying inside a TFR helps to flag the flight to other users.

The “innocent bystander” crews, who had another vehicle breach their airspace, said they would like the USS to tell them when that breaching vehicle (or vehicle that has an emergency and is transiting) has left their airspace, because they would like to know that it is safe to continue their mission at that point. One crew said that although their goal was to get their vehicle safely on the ground, they waited for the vehicle-in-trouble to land before they stopped their loiter, just to be sure that they would avoid a conflict.

5.5.5 Procedures: Emergency

In the case where there is an emergency, rather than have a TFR that requires operations to leave the airspace, crews discussed putting procedures in place where they make way for the emergency flight, “pull to the side of the road” to allow the flight to pass, but do not have to exit. From the other side of the problem, as an emergency vehicle, it would be good to know that the users of the airspace were being compliant and had vacated the space that you are now working in. The emergency responder would want to know that previous volumes were being closed and vehicles are down. 5.5.6 Procedures: Gaming the System

In general discussion, participants talked about some ways that bad actors could game the UTM system. They discussed that if you went rogue during the contingency event, this status then gives you priority over others, with the assumption that you are a disabled flight and you need direct routes to RTB. However, this creates a loophole that operators could take advantage of. If they submit a

very small volume but then fly their mission in rogue status, under the contingency management rules this would give them a priority status over other vehicles to essentially bump accepted users out of their space, even though they were not in distress.