Narrative:

I was working ARTCC as the radar/interphone controller. I recognized a potential confliction between a widebody transport #1 and a widebody transport #2 at FL330 on converging courses. When the L1011 entered my airspace, communication had not been established. I then called the previous sector to re-atttempt communication xfer, with no success. I then asked my supervisor to initiate a commercial radio call to widebody transport #2 flight. This too was unsuccessful. Thereafter, the xferring controller for the widebody transport #2 flight informed me that they had also lost communication with the flight. A commercial radio call to widebody transport #2 flight was also unsuccessful. I informed my supervisor that the situation was getting critical (about 10 mins to target merge) I attempted to establish communication with ATC emergency guard frequency 121.5 with no success. I alerted the ZKC receiving controller of the situation. Next, I observed the 2 targets merge, and come out the other side. Supplemental information from acn 429530: TCASII on either aircraft would have stopped the entire chain of events. Supplemental information from acn 429610: neither aircraft was equipped with TCASII.

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Original NASA ASRS Text

Title: LOSS OF RADIO COM RESULTED IN A NEAR MISS.

Narrative: I WAS WORKING ARTCC AS THE RADAR/INTERPHONE CTLR. I RECOGNIZED A POTENTIAL CONFLICTION BTWN A WDB #1 AND A WDB #2 AT FL330 ON CONVERGING COURSES. WHEN THE L1011 ENTERED MY AIRSPACE, COM HAD NOT BEEN ESTABLISHED. I THEN CALLED THE PREVIOUS SECTOR TO RE-ATTTEMPT COM XFER, WITH NO SUCCESS. I THEN ASKED MY SUPVR TO INITIATE A COMMERCIAL RADIO CALL TO WDB #2 FLT. THIS TOO WAS UNSUCCESSFUL. THEREAFTER, THE XFERRING CTLR FOR THE WDB #2 FLT INFORMED ME THAT THEY HAD ALSO LOST COM WITH THE FLT. A COMMERCIAL RADIO CALL TO WDB #2 FLT WAS ALSO UNSUCCESSFUL. I INFORMED MY SUPVR THAT THE SIT WAS GETTING CRITICAL (ABOUT 10 MINS TO TARGET MERGE) I ATTEMPTED TO ESTABLISH COM WITH ATC EMER GUARD FREQ 121.5 WITH NO SUCCESS. I ALERTED THE ZKC RECEIVING CTLR OF THE SIT. NEXT, I OBSERVED THE 2 TARGETS MERGE, AND COME OUT THE OTHER SIDE. SUPPLEMENTAL INFO FROM ACN 429530: TCASII ON EITHER ACFT WOULD HAVE STOPPED THE ENTIRE CHAIN OF EVENTS. SUPPLEMENTAL INFO FROM ACN 429610: NEITHER ACFT WAS EQUIPPED WITH TCASII.

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.