Narrative:

On climb out we never received instructions to transfer from tower frequency to departure frequency. I've noticed in operating out of den, the handoff is often later than what I was accustomed to at stapleton or other major airports. Therefore, I waited until climbing through 8000 ft MSL before asking the tower if he wanted us to switch over. If there was a response, it was very weak and unintelligible to both me and my first officer. Also, during this time, we experienced a one-time 'traffic' alert on our TCASII. We acquired this target above us at 11000 ft and a couple mi to our 11 O'clock position. Approaching 9000 ft for 10000 ft I switched to departure to check in after unsuccessfully trying to communicate with tower. Upon leveling at 10000 ft, we received an 'RA' on our TCASII, which the first officer responded to appropriately by following the climb command on our eadi. Following the RA resulted in a 400 ft overshoot of our initial assigned altitude. When checking in with departure, we advised the controller of our RA and deviation, which was then being corrected. The icon representing the threat aircraft appeared to correspond to a visually acquired aircraft well off to our right (approximately 2 plus NM) and approximately 1000 ft below us. We never did find out whether ATC had attempted to contact us prior to or during the aural 'TA' as the tower didn't appear to be responding to our query, and departure was too busy with other aircraft and working in a limited airspace environment due to a thunderstorm north of the field.

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Original NASA ASRS Text

Title: AN ACR FLC RESPONDED TO A TCASII RA WHICH OCCURRED DURING A FREQ CHANGE. THE CAPT RPTS THAT INCREASED CTLR WORKLOAD DUE TO FREQ CONGESTION AND TSTMS NEAR THE ARPT MAY HAVE CONTRIBUTED TO A LATE FREQ CHANGE AND THE RESULTING CONFLICT.

Narrative: ON CLBOUT WE NEVER RECEIVED INSTRUCTIONS TO TRANSFER FROM TWR FREQ TO DEP FREQ. I'VE NOTICED IN OPERATING OUT OF DEN, THE HDOF IS OFTEN LATER THAN WHAT I WAS ACCUSTOMED TO AT STAPLETON OR OTHER MAJOR ARPTS. THEREFORE, I WAITED UNTIL CLBING THROUGH 8000 FT MSL BEFORE ASKING THE TWR IF HE WANTED US TO SWITCH OVER. IF THERE WAS A RESPONSE, IT WAS VERY WEAK AND UNINTELLIGIBLE TO BOTH ME AND MY FO. ALSO, DURING THIS TIME, WE EXPERIENCED A ONE-TIME 'TFC' ALERT ON OUR TCASII. WE ACQUIRED THIS TARGET ABOVE US AT 11000 FT AND A COUPLE MI TO OUR 11 O'CLOCK POS. APCHING 9000 FT FOR 10000 FT I SWITCHED TO DEP TO CHK IN AFTER UNSUCCESSFULLY TRYING TO COMMUNICATE WITH TWR. UPON LEVELING AT 10000 FT, WE RECEIVED AN 'RA' ON OUR TCASII, WHICH THE FO RESPONDED TO APPROPRIATELY BY FOLLOWING THE CLB COMMAND ON OUR EADI. FOLLOWING THE RA RESULTED IN A 400 FT OVERSHOOT OF OUR INITIAL ASSIGNED ALT. WHEN CHKING IN WITH DEP, WE ADVISED THE CTLR OF OUR RA AND DEV, WHICH WAS THEN BEING CORRECTED. THE ICON REPRESENTING THE THREAT ACFT APPEARED TO CORRESPOND TO A VISUALLY ACQUIRED ACFT WELL OFF TO OUR R (APPROX 2 PLUS NM) AND APPROX 1000 FT BELOW US. WE NEVER DID FIND OUT WHETHER ATC HAD ATTEMPTED TO CONTACT US PRIOR TO OR DURING THE AURAL 'TA' AS THE TWR DIDN'T APPEAR TO BE RESPONDING TO OUR QUERY, AND DEP WAS TOO BUSY WITH OTHER ACFT AND WORKING IN A LIMITED AIRSPACE ENVIRONMENT DUE TO A TSTM N OF THE FIELD.

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.