Narrative:

While I was prebriefing to relieve the AR1 position I heard aircraft X call for IFR clearance on 118.05; the clearance frequency on the ground at jvy. No clearance was available for that call sign so the AR1 controller told the pilot to contact flight service. I was then briefed and assumed the position. After about 10 minutes; aircraft X called back saying he couldn't reach flight service. With low workload I decided to take the aircraft info and have the data put in a flight plan. Data handed me the strip a minute or two later and I told aircraft X that clearance was available and advise ready to copy. After an affirmative reply I issued the clearance with altitudes of maintain 3000; expect 8000 10 minutes after departure and told the pilot 'hold for release; advise ready for departure'. The pilot replied that he was ready. Then I noticed his data tag appear less than a mile behind aircraft Y westbound at 6000 and the data tag said 5500. I asked aircraft X if he was airborne and he said affirmative. I immediately issued the traffic of aircraft Y to aircraft X and aircraft X said he had the traffic in sight. I said maintain visual separation with that traffic; maintain 6000; fly heading 180. I then told the supervisor that I had two IFR aircraft in close proximity. The supervisor listened to the tapes and passed along to another controller to issue the brasher warning. I should've made sure that aircraft X was on the ground prior to issuing the clearance; since he wasn't I would've issued an airborne IFR with considerations to the conflict with aircraft Y.

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Original NASA ASRS Text

Title: SDF TRACON Controller reported giving an IFR clearance to an aircraft he thought was on the ground. Aircraft was actually airborne and in close proximity to another aircraft leading to a loss of separation.

Narrative: While I was prebriefing to relieve the AR1 position I heard Aircraft X call for IFR clearance on 118.05; the clearance frequency on the ground at JVY. No clearance was available for that call sign so the AR1 controller told the pilot to contact flight service. I was then briefed and assumed the position. After about 10 minutes; Aircraft X called back saying he couldn't reach flight service. With low workload I decided to take the aircraft info and have the data put in a flight plan. Data handed me the strip a minute or two later and I told Aircraft X that clearance was available and advise ready to copy. After an affirmative reply I issued the clearance with altitudes of maintain 3000; expect 8000 10 minutes after departure and told the pilot 'Hold for Release; Advise Ready for Departure'. The pilot replied that he was ready. Then I noticed his data tag appear less than a mile behind Aircraft Y westbound at 6000 and the data tag said 5500. I asked Aircraft X if he was airborne and he said affirmative. I immediately issued the traffic of Aircraft Y to Aircraft X and Aircraft X said he had the traffic in sight. I said maintain visual separation with that traffic; maintain 6000; fly heading 180. I then told the supervisor that I had two IFR aircraft in close proximity. The supervisor listened to the tapes and passed along to another controller to issue the Brasher Warning. I should've made sure that Aircraft X was on the ground prior to issuing the clearance; since he wasn't I would've issued an airborne IFR with considerations to the conflict with Aircraft Y.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.