Narrative:

Cruising at FL310, deviating around numerous thunderstorms. ZKC switched us over to ZDV. Checked in with ZDV, gave our altitude and notified them we were deviating for WX (previously approved by ZKC). Did not receive a response from ZDV, although we could hear the controller talking to other aircraft. Several other aircraft also attempted to check in with no response from center. The frequency was very congested due to numerous aircraft requiring WX deviations. We made numerous attempts to check in, including identing on our transponder. We had our TCASII on, and noticed an aircraft also at FL310 about 10-12 mi ahead of us going from our right to left. We turned approximately 20 degrees right to increase separation and pass well behind him. About the same time the controller finally contacted us and gave us instructions to turn right also, which we were already doing. Our closest point with the other aircraft was about 6-8 mi. We did not get any TCASII TA's, as we were not that close. The cause of this incident can be attributed to the heavy workload the controller had along with too many xmissions on the frequency, causing many of them to be blocked out. The TCASII proved invaluable. Without it, our closure distance with the other aircraft would have been much closer.

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Original NASA ASRS Text

Title: FLC OF AN MLG ACR ACFT TOOK EVASIVE ACTION IN RESPONSE TO A TCASII RA DUE TO CTLR WORKLOAD DISTR.

Narrative: CRUISING AT FL310, DEVIATING AROUND NUMEROUS TSTMS. ZKC SWITCHED US OVER TO ZDV. CHKED IN WITH ZDV, GAVE OUR ALT AND NOTIFIED THEM WE WERE DEVIATING FOR WX (PREVIOUSLY APPROVED BY ZKC). DID NOT RECEIVE A RESPONSE FROM ZDV, ALTHOUGH WE COULD HEAR THE CTLR TALKING TO OTHER ACFT. SEVERAL OTHER ACFT ALSO ATTEMPTED TO CHK IN WITH NO RESPONSE FROM CTR. THE FREQ WAS VERY CONGESTED DUE TO NUMEROUS ACFT REQUIRING WX DEVS. WE MADE NUMEROUS ATTEMPTS TO CHK IN, INCLUDING IDENTING ON OUR XPONDER. WE HAD OUR TCASII ON, AND NOTICED AN ACFT ALSO AT FL310 ABOUT 10-12 MI AHEAD OF US GOING FROM OUR R TO L. WE TURNED APPROX 20 DEGS R TO INCREASE SEPARATION AND PASS WELL BEHIND HIM. ABOUT THE SAME TIME THE CTLR FINALLY CONTACTED US AND GAVE US INSTRUCTIONS TO TURN R ALSO, WHICH WE WERE ALREADY DOING. OUR CLOSEST POINT WITH THE OTHER ACFT WAS ABOUT 6-8 MI. WE DID NOT GET ANY TCASII TA'S, AS WE WERE NOT THAT CLOSE. THE CAUSE OF THIS INCIDENT CAN BE ATTRIBUTED TO THE HVY WORKLOAD THE CTLR HAD ALONG WITH TOO MANY XMISSIONS ON THE FREQ, CAUSING MANY OF THEM TO BE BLOCKED OUT. THE TCASII PROVED INVALUABLE. WITHOUT IT, OUR CLOSURE DISTANCE WITH THE OTHER ACFT WOULD HAVE BEEN MUCH CLOSER.

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.