*4.4. Summary*

For all the problem classes, the zoning approach outperforms the other considered UAV deployment strategies in terms of the safety of UAVs and the service quality for demands. The zoning approach shows that it can guarantee a sufficient gap between operating UAVs and that it can serve more demands at a faster rate than the other benchmark strategies. All of these findings are critical to implement a UTM with distributed workloads for collision avoidance and to provide acceptable service quality to customers.

#### **5. Discussion**
