Narrative:

I was working approach/departure (combined) when traffic started to increase to an unusually heavy level. Atx X, an small transport, departed oma for sioux falls via sioux city. On departure, he apparently had not turned on his transponder, because his data block had not tagged up to his target. He was issued a turn on course and climbed to 6000'. With traffic picking up, I was going to verify that his transponder was on, after completing other higher priority duties. I failed to remember to complete this requirement, and subsequently forgot atx X as he proceeded on course. Sioux city approach was being worked by ZMP due to maintenance being performed on sux radar. I had summoned for help on position, and after traffic had reduced a bit. The other controller asked if I had switched atx X to ZMP frequency. I then remembered atx X, called him and discovered he was over the sux VOR at 6000', completely off my scope, and not handed off to ZMP. After coordination with ZMP, they found him and I then xferred him to a ZMP frequency. Oma tower is required to inform departure control when departures don't acquire their data block, but in this instance they did not. Ultimately, it was my failure to verify if atx X had his transponder on, and certainly to know where all my traffic is at all times.

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Original NASA ASRS Text

Title: ATX X ENTERED ZMP AIRSPACE WITHOUT RADAR HANDOFF. OPERATIONAL DEVIATION.

Narrative: I WAS WORKING APCH/DEP (COMBINED) WHEN TFC STARTED TO INCREASE TO AN UNUSUALLY HEAVY LEVEL. ATX X, AN SMT, DEPARTED OMA FOR SIOUX FALLS VIA SIOUX CITY. ON DEP, HE APPARENTLY HAD NOT TURNED ON HIS XPONDER, BECAUSE HIS DATA BLOCK HAD NOT TAGGED UP TO HIS TARGET. HE WAS ISSUED A TURN ON COURSE AND CLBED TO 6000'. WITH TFC PICKING UP, I WAS GOING TO VERIFY THAT HIS XPONDER WAS ON, AFTER COMPLETING OTHER HIGHER PRIORITY DUTIES. I FAILED TO REMEMBER TO COMPLETE THIS REQUIREMENT, AND SUBSEQUENTLY FORGOT ATX X AS HE PROCEEDED ON COURSE. SIOUX CITY APCH WAS BEING WORKED BY ZMP DUE TO MAINT BEING PERFORMED ON SUX RADAR. I HAD SUMMONED FOR HELP ON POS, AND AFTER TFC HAD REDUCED A BIT. THE OTHER CTLR ASKED IF I HAD SWITCHED ATX X TO ZMP FREQ. I THEN REMEMBERED ATX X, CALLED HIM AND DISCOVERED HE WAS OVER THE SUX VOR AT 6000', COMPLETELY OFF MY SCOPE, AND NOT HANDED OFF TO ZMP. AFTER COORD WITH ZMP, THEY FOUND HIM AND I THEN XFERRED HIM TO A ZMP FREQ. OMA TWR IS REQUIRED TO INFORM DEP CTL WHEN DEPS DON'T ACQUIRE THEIR DATA BLOCK, BUT IN THIS INSTANCE THEY DID NOT. ULTIMATELY, IT WAS MY FAILURE TO VERIFY IF ATX X HAD HIS XPONDER ON, AND CERTAINLY TO KNOW WHERE ALL MY TFC IS AT ALL TIMES.

Data retrieved from NASA's ASRS site as of July 2007 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.