# ATC Human Factors Involved in RPAS Contingency Management in Non-Segregated Airspace
## 3 Experiments
### Real-Time Simulation Experiments  
Within the ERAINT project, 100 successful simulations were carried out, covering more than 90 h of flight time, of which almost 47 h corresponded to the flight time in which the simulated RPAS was under active control by a human ATC in one of the active sectors selected for the simulation exercise under consideration. Within the contingency management study, 52 simulations with 42 flight hours were conducted over thirty months distributed among the selected scenarios (a and c-f), which included several missions that contemplated using flight-intent technology and RPAS contingencies. Tables 5 and 6 show the total number of simulations and the RPAS flight time distribution that we conducted oriented to the evaluation of contingency management. The exercises were conducted in two separate flight campaigns (referred to as Run1 and Run2) carried out a few months apart. The simulation times are reported in minutes, indicating the time in which RPAS is active within each sector and the total simulation time. In addition, the total number of simulations for each scenario is specified, indicating the number of times an ATCO has actively manned each sector. \begin{table}
\begin{tabular}{c c c} \hline \hline
**Scenario ID** & **Description** & **Pilot-ATC Communications** \\ \hline Scenario (a) & Baseline. No RPAS operating & Radiotelephone \\ \hline Scenario (b) & RPAS operating. No contingency. With the support of flight-intent technology & Radiotelephone \\ \hline Scenario (c) & RPAS operating. Engine failure contingency. Without the support of flight-intent technology & Radiotelephone \\ \hline Scenario (d) & RPAS operating. Engine failure contingency. Support of flight-intent technology & Radiotelephone/ADS-C datalink \\ \hline Scenario (e) & RPAS operating. Lost-link contingency. Without the support of flight-intent technology & Radiotelephone \\ \hline Scenario (f) & RPAS operating. Lost-link contingency. Support of flight-intent technology & Radiotelephone/ADS-C datalink \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Communication technologies per scenario. During the simulations, the predefined contingency events were planned, which triggered the corresponding tasks according to the sector operating and the simulation events specified to occur in each sector. The most common events are: a manned or RPAS flight enters or exits an ATC sector requiring coordination, an aircraft requires climb/descent according to their transition to/from an airport, the separation between aircrafts needs to be maintained by vectoring or altitude changes, an RPAS declares an emergency, etc. Hence, each ATC working position performs several tasks unknown to the controller at the beginning of the simulation. Additionally, a collection of 37 simulation exercises, covering approximately 18.5 h of flight time, would be employed as a further reference for the baseline scenarios a-b. Those simulations include nominal mission-oriented operations mostly executed with the MQ-9 RPAS. We also study the use of flight-intent technology. The flight intent is aircraft-derived data describing its imminent future trajectory. Flight intent can be calculated by the FMS (Flight Management System) onboard the aircraft and broadcast through the ADS-B/ADS-C out communication technology. It was proposed by EUROCONTROL [25] to improve the ATC tasks related to conflict detection. [PERSON] et al. [26] demonstrated that RPAS autopilots could also calculate and share the flight intent to be used as a valuable input to support ground-based collision avoidance systems. Flight-intent functionality is added to our simulation environment because it is expected to reduce the uncertainty of the trajectory prediction in the short term by providing ATC with the most accurate calculation of the following legs to fly [8].