Narrative:

Departing runway 8, den. We had climbed about 500 ft AGL and tower (local) advised us of an opposite direction learjet, 3 mi, our altitude. We scanned visually and displayed TCASII map page. First officer spotted aircraft first and pointed target out to me. We both saw exhaust and then aircraft coming right at us on a collision course. I (PF) maneuvered our aircraft to the south, but no radical turn was required or desired, as flaps were still extended at takeoff position and airspeed was relatively slow. We idented the aircraft as a learjet, and noticed that the landing gear on the learjet was not extended. We configured for climb and contacted departure. My thanks to the tower controller for alerting us to the threat. This situation may have occurred because the learjet misidented den airport for front range airport, approximately 3 NM to the southeast. This was as close as I've ever come to a head-on midair collision, and it occurred in class B airspace at a very inopportune time. TCASII activated too late to be any real help, due to being inhibited at low altitudes after takeoff.

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Original NASA ASRS Text

Title: 500 FT AGL ACR ADVISED OF UNCTLED TFC IN CLASS B AIRSPACE AT 12 O'CLOCK OPPOSITE DIRECTION. TFC SIGHTED AND AVOIDED. TCASII ADVISORIES LATE BECAUSE OF DESIGN LIMITS.

Narrative: DEPARTING RWY 8, DEN. WE HAD CLBED ABOUT 500 FT AGL AND TWR (LCL) ADVISED US OF AN OPPOSITE DIRECTION LEARJET, 3 MI, OUR ALT. WE SCANNED VISUALLY AND DISPLAYED TCASII MAP PAGE. FO SPOTTED ACFT FIRST AND POINTED TARGET OUT TO ME. WE BOTH SAW EXHAUST AND THEN ACFT COMING RIGHT AT US ON A COLLISION COURSE. I (PF) MANEUVERED OUR ACFT TO THE S, BUT NO RADICAL TURN WAS REQUIRED OR DESIRED, AS FLAPS WERE STILL EXTENDED AT TKOF POS AND AIRSPD WAS RELATIVELY SLOW. WE IDENTED THE ACFT AS A LEARJET, AND NOTICED THAT THE LNDG GEAR ON THE LEARJET WAS NOT EXTENDED. WE CONFIGURED FOR CLB AND CONTACTED DEP. MY THANKS TO THE TWR CTLR FOR ALERTING US TO THE THREAT. THIS SIT MAY HAVE OCCURRED BECAUSE THE LEARJET MISIDENTED DEN ARPT FOR FRONT RANGE ARPT, APPROX 3 NM TO THE SE. THIS WAS AS CLOSE AS I'VE EVER COME TO A HEAD-ON MIDAIR COLLISION, AND IT OCCURRED IN CLASS B AIRSPACE AT A VERY INOPPORTUNE TIME. TCASII ACTIVATED TOO LATE TO BE ANY REAL HELP, DUE TO BEING INHIBITED AT LOW ALTS AFTER TKOF.

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.