Narrative:

Air carrier X was encountering thunderstorms at 12 O'clock, we were on V143 swbound. ATC issued us a clearance to deviate left of course as necessary for WX and to notify when able to come back right to original course. I read back clearance including that we would be able to come back right on course in about 15-20 mi. We began encountering moderate precipitation. Our communications became slightly static (reception from center) but readable. After about 15 mi I heard center controller xmissions breaking up. I immediately transmitted that center was totally unreadable. Approximately 1 min later, I heard center saying he was on backup transmitter telling us to make a 180 degree turn. We started left turn and I advised him of this. He then told me to squawk emergency and said we had aircraft Y at 12 O'clock and 2 mi, same altitude. I feel the controller was controling too many aircraft which were deviating for WX and temporarily forgot about us. Also, the precipitation in which we were encountering may have disrupted our communications.

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Original NASA ASRS Text

Title: ACR X DEVIATING FOR WX HAD LTSS FROM ACFT Y ASSIGNED SAME ALT. SYS ERROR. POTENTIAL CONFLICT LTSS.

Narrative: ACR X WAS ENCOUNTERING TSTMS AT 12 O'CLOCK, WE WERE ON V143 SWBOUND. ATC ISSUED US A CLRNC TO DEVIATE L OF COURSE AS NECESSARY FOR WX AND TO NOTIFY WHEN ABLE TO COME BACK R TO ORIGINAL COURSE. I READ BACK CLRNC INCLUDING THAT WE WOULD BE ABLE TO COME BACK RIGHT ON COURSE IN ABOUT 15-20 MI. WE BEGAN ENCOUNTERING MODERATE PRECIPITATION. OUR COMS BECAME SLIGHTLY STATIC (RECEPTION FROM CTR) BUT READABLE. AFTER ABOUT 15 MI I HEARD CTR CTLR XMISSIONS BREAKING UP. I IMMEDIATELY XMITTED THAT CTR WAS TOTALLY UNREADABLE. APPROX 1 MIN LATER, I HEARD CTR SAYING HE WAS ON BACKUP XMITTER TELLING US TO MAKE A 180 DEG TURN. WE STARTED L TURN AND I ADVISED HIM OF THIS. HE THEN TOLD ME TO SQUAWK EMER AND SAID WE HAD ACFT Y AT 12 O'CLOCK AND 2 MI, SAME ALT. I FEEL THE CTLR WAS CTLING TOO MANY ACFT WHICH WERE DEVIATING FOR WX AND TEMPORARILY FORGOT ABOUT US. ALSO, THE PRECIPITATION IN WHICH WE WERE ENCOUNTERING MAY HAVE DISRUPTED OUR COMS.

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.