Small Transport
Air Traffic Control Fully Certified
Air Traffic Control Time Certified In Pos 1 (yrs) 2.0
Communication Breakdown; Situational Awareness
ATC Issue All Types; Conflict Airborne Conflict; Deviation / Discrepancy - Procedural Published Material / Policy
Flight Crew Requested ATC Assistance / Clarification
Aircraft; Procedure; Manuals; Environment - Non Weather Related
Aircraft X cancelled their IFR about 10 miles from the airport approaching Runway 10. Aircraft Y was waiting on Runway 28 ready for departure. I told both aircraft about each other and released Aircraft Y at their discretion. Aircraft Y waited until Aircraft X was very close before departing. I thought Aircraft Y would wait until Aircraft X landed; but instead they pushed it and got close enough to Aircraft X that the pilot of Aircraft X called the Center wondering what was going on.The pilots need to talk to each other on local frequency and should know that if they go VFR; controllers will pass along their information; but they don't separate them from other IFR aircraft in the terminal environment.
ZDV Center Controller reported he was advised by an arrival to an uncontrolled airport that another aircraft had been given a departure clearance by another controller to departed opposite direction and too close to them.