Narrative:

Busy departure rush from traffic leaving football game. 15 mi in trail restr from ZAU propeller/propeller and jet/jet, nearly all going same direction. I put a citation aircraft Y into position and hold on runway, then taxi off runway to depart the twin cessna aircraft Y behind him (for propeller/propeller mi in trail). There wasn't the 15 mi in trail for the citation to depart from the first jet. Twin cessna departed on 243 degrees (on course). Then departed another twin cessna on a 360 degree heading -- switched first twin, put citation into position and hold, observed 360 degree turn and departed citation on 240 degree heading. Switched second twin, then switched citation. Radar then called me to turn the citation left. I stated 'your control.' I observed on the d-brite the citation 3 mi in trail climbing to 3000 ft. I observed the jet in a turn to the right (270 degrees) and then the conflict alert was activated. The 2 planes came within 300 ft and 1 mi. The twin was not turned. The twin was on a timed out flight plan and did not tag initially off the airport. However, when the citation was departed and after he was switched to departure, there was a tag on both planes. The twin was cleared up to 8000 ft on initial contact off the airport, and I did not notice his altitude nor the untagged target prior to departing the citation.

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Original NASA ASRS Text

Title: SBN TWR CTLR DOES NOT RECOGNIZE THAT THE FIRST OF 3 DEPARTING ACFT DOES NOT RADAR AUTO-ACQUIRE, THUS SUBSEQUENT ACFT CLRED FOR TKOF ARE NOT AFFORDED APPROPRIATE DEP RADAR SEPARATION.

Narrative: BUSY DEP RUSH FROM TFC LEAVING FOOTBALL GAME. 15 MI IN TRAIL RESTR FROM ZAU PROP/PROP AND JET/JET, NEARLY ALL GOING SAME DIRECTION. I PUT A CITATION ACFT Y INTO POS AND HOLD ON RWY, THEN TAXI OFF RWY TO DEPART THE TWIN CESSNA ACFT Y BEHIND HIM (FOR PROP/PROP MI IN TRAIL). THERE WASN'T THE 15 MI IN TRAIL FOR THE CITATION TO DEPART FROM THE FIRST JET. TWIN CESSNA DEPARTED ON 243 DEGS (ON COURSE). THEN DEPARTED ANOTHER TWIN CESSNA ON A 360 DEG HDG -- SWITCHED FIRST TWIN, PUT CITATION INTO POS AND HOLD, OBSERVED 360 DEG TURN AND DEPARTED CITATION ON 240 DEG HDG. SWITCHED SECOND TWIN, THEN SWITCHED CITATION. RADAR THEN CALLED ME TO TURN THE CITATION L. I STATED 'YOUR CTL.' I OBSERVED ON THE D-BRITE THE CITATION 3 MI IN TRAIL CLBING TO 3000 FT. I OBSERVED THE JET IN A TURN TO THE R (270 DEGS) AND THEN THE CONFLICT ALERT WAS ACTIVATED. THE 2 PLANES CAME WITHIN 300 FT AND 1 MI. THE TWIN WAS NOT TURNED. THE TWIN WAS ON A TIMED OUT FLT PLAN AND DID NOT TAG INITIALLY OFF THE ARPT. HOWEVER, WHEN THE CITATION WAS DEPARTED AND AFTER HE WAS SWITCHED TO DEP, THERE WAS A TAG ON BOTH PLANES. THE TWIN WAS CLRED UP TO 8000 FT ON INITIAL CONTACT OFF THE ARPT, AND I DID NOT NOTICE HIS ALT NOR THE UNTAGGED TARGET PRIOR TO DEPARTING THE CITATION.

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.