Narrative:

I was working the trac position in the tower with radar combined. Traffic was getting busy and was unable to split off the sectors. By the time I saw the conflict I was on the line with oakland center coordinating a satellite departure and turned the aircraft involved too late. Air carrier X advised they were responding to a TCAS RA with air carrier Y who also said they were responding. I gave air carrier X a descent and saw air carrier Y climb approximately 200 feet. The fact of the matter is; if I would have had enough staffing to split the radar and still get training accomplished without having to work position this would not have happened.

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Original NASA ASRS Text

Title: RNO controller experienced a loss of separation event with two air carrier when staffing and training required combined position operation/s.

Narrative: I was working the TRAC position in the Tower with RADAR combined. Traffic was getting busy and was unable to split off the sectors. By the time I saw the conflict I was on the line with Oakland Center coordinating a satellite departure and turned the aircraft involved too late. Air Carrier X advised they were responding to a TCAS RA with Air Carrier Y who also said they were responding. I gave Air Carrier X a descent and saw Air Carrier Y climb approximately 200 feet. The fact of the matter is; if I would have had enough staffing to split the RADAR and still get training accomplished without having to work position this would not have happened.

Data retrieved from NASA's ASRS site as of April 2012 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.