Small Aircraft
Air Traffic Control Fully Certified
Air Traffic Control Time Certified In Pos 1 (yrs) 1
Communication Breakdown; Confusion; Distraction; Situational Awareness
ATC Issue All Types; Conflict NMAC; Deviation / Discrepancy - Procedural Clearance
Human Factors; Procedure
CGF tower called for IFR release on Aircraft X. I issued release with a right turn heading 100. As I began a position relief briefing; CGF tower called for another IFR release on Aircraft Y. I issued 'visual separation approved between Aircraft X and Aircraft Y; Aircraft Y released heading 210.' As a tower controller myself; I believed that CGF tower would let Aircraft X run out for a couple of miles and then release Aircraft Y with a turn off the deck inside of Aircraft X and maintain tower visual until divergence was established. What CGF tower did was keep Aircraft Y on runway heading for nearly 5 miles. The controller who relieved me called to CGF tower to ask them to leave Aircraft Y on runway heading. During the call CGF tower informed the relieving controller that Aircraft Y was in the turn. I don't recall the relieving controller's response. Aircraft X and Aircraft Y's targets merged about 7 mile east of CGF at 030. Aircraft Y checked on to the frequency as the targets were merged saying that he had Aircraft X in sight. I don't know at what point Aircraft Y got Aircraft X in sight or what the CGF tower controllers actions were while Aircraft Y was on their frequency. I don't know how to prevent this from happening again. The CGF tower controller and I obviously had very different ideas about how visual separation would be used in this operation. It is possible that Aircraft Y had Aircraft X in sight before the CGF tower controller turned Aircraft Y off of runway heading.
CLE Controller reported of a situation where he was not sure as to what type of separation the Tower was using. Controller reported thinking that the Tower would do what he was thinking; but did not. Aircraft had the other in sight but reporter did not know when this visual separation had happened.