Air Traffic Control Fully Certified
Air Traffic Control Time Certified In Pos 1 (yrs) 12.0
Situational Awareness; Communication Breakdown
ATC Issue All Types; Conflict Airborne Conflict; Deviation / Discrepancy - Procedural Clearance; Deviation / Discrepancy - Procedural Published Material / Policy; Ground Incursion Runway
Air Traffic Control Issued Advisory / Alert; Flight Crew Requested ATC Assistance / Clarification; Flight Crew Returned To Departure Airport
Aircraft; Airspace Structure; Procedure; Human Factors
Aircraft X was on the ground requesting an IFR clearance. I instructed the aircraft to Hold for Release and then issued the clearance and to advise when ready for departure. After listening to the recording of the incident; I did not receive a read back of the hold for release. I then cleared Aircraft Y for an ILS approach. Right after Aircraft Y passed the final approach fix Aircraft X comes off of opposite direction. I immediately issued a traffic alert to Aircraft Y and he replied that he was looking for traffic. I then issued traffic to Aircraft X to which he replied 'we see the traffic passing underneath us.' I informed Aircraft X that his instructions were to hold for release. I also instructed Aircraft X to maintain VFR. I then advised him of additional traffic inbound to which he replied 'we're just going to cancel and return to ....'I should have been clearer to the aircraft on the ground that he is not released for departure due to inbound traffic.
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Two ZID Center Controllers reported that an aircraft had been issued an IFR clearance that was supposed to hold for departure; but departed into traffic landing opposite direction.