This paper proposes to create a taxonomy of separation conflicts between Unmanned Aerial Systems (UAS) and intruding aircrafts to facilitate its insertion in non-segregated airspace. The classification is created according to the relative speeds, angular geometry, initial intent, etc. A catalog of separation maneuvers that best fit each scenario is introduced and evaluated through a real-time simulation environment. This advisory mechanism will benefit both the UAS pilot and the ATCo in order to negotiate the best suited separation maneuver. Eventually, the same strategy can be employed as an autonomous separation system on-board a UAS that suffers a lost-link contingency, alleviating its negative impact in the airspace.