Narrative:

After a local flight southwest of oshkosh; I called oshkosh tower and reported 'fisk;' (VFR reporting point about 6.5 NM southwest of the field) inbound for pattern work. The pattern for [runway] 9/27 was very busy so I requested [runway] 18/36 for touch & goes - common practice in oshkosh as the runways don't intersect and are in the shape of a capitol 'T.' tower acknowledged and asked me to make right traffic for 18; remaining south of 9/27; and report 2 NM southwest. I acknowledged and proceeded to set up for a right base for 18. During this time I had a high workload watching for traffic on the busy 9/27 to my left (north) and keeping lateral separation from aircraft on final for 9 as I aligned on base for 18; while at the same time managing my own approach. About 3 NM away from the field on right base for 18; a king air crossed in front of me at approximately my altitude; apparently on a right base for 9. I cannot accurately recall the lateral distance; but it was close enough for me to feel very uncomfortable. I would estimate 100-300 yards. There was no mention of the encounter or our positions by either of us (the planes involved) or the controller.I can see two ways in which I may have erred: a) I was a little farther north than tower might have expected to find me; as I was set up on more of a long base rather than a southwest approach to the airport. B) I did not look right anywhere near enough while on base. I was fixated on traffic in the pattern for 9/27 and my own approach; unaware that traffic was approaching from the south. The king air was communicating with the tower and I probably missed getting a good picture of where he was. Nevertheless; I feel the controller should have called out the traffic to me and the king air as we made our respective approaches. I will note that it was a single controller working two runways during a particularly busy period; but the encounter was simply too close for there not to be a mention of it by ATC.

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Original NASA ASRS Text

Title: Pilot of a light single engine aircraft reported NMAC with a King Air in the Oshkosh pattern area. Reporter mentioned he would have appreciated a heads-up from ATC.

Narrative: After a local flight southwest of Oshkosh; I called Oshkosh Tower and reported 'Fisk;' (VFR reporting point about 6.5 NM southwest of the field) inbound for pattern work. The pattern for [Runway] 9/27 was very busy so I requested [Runway] 18/36 for touch & goes - common practice in Oshkosh as the runways don't intersect and are in the shape of a capitol 'T.' Tower acknowledged and asked me to make right traffic for 18; remaining south of 9/27; and report 2 NM southwest. I acknowledged and proceeded to set up for a right base for 18. During this time I had a high workload watching for traffic on the busy 9/27 to my left (north) and keeping lateral separation from aircraft on final for 9 as I aligned on base for 18; while at the same time managing my own approach. About 3 NM away from the field on right base for 18; a King Air crossed in front of me at approximately my altitude; apparently on a right base for 9. I cannot accurately recall the lateral distance; but it was close enough for me to feel very uncomfortable. I would estimate 100-300 yards. There was no mention of the encounter or our positions by either of us (the planes involved) or the Controller.I can see two ways in which I may have erred: a) I was a little farther north than Tower might have expected to find me; as I was set up on more of a long base rather than a southwest approach to the airport. b) I did not look right anywhere near enough while on base. I was fixated on traffic in the pattern for 9/27 and my own approach; unaware that traffic was approaching from the south. The King Air was communicating with the Tower and I probably missed getting a good picture of where he was. Nevertheless; I feel the Controller should have called out the traffic to me and the King Air as we made our respective approaches. I will note that it was a single Controller working two runways during a particularly busy period; but the encounter was simply too close for there not to be a mention of it by ATC.

Data retrieved from NASA's ASRS site as of July 2013 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.