Narrative:

Corp Y was climbing to FL310. Air carrier X was at FL290. Corp Y was vectored for climb around X. Air carrier X was vectored, but would not listen to the frequency. Air carrier X was called 3 times and never acknowledged. Y was given an additional vector to compensate for X. Air carrier X answered the fourth call, was finally given a turn and descent. Air carrier X questioned the clearance. Was advised that he had been called for 30 mi. At this point, sep was lost. If aircraft was listening to frequency and had taken the first clearance, there would have been no problem. My suggestion is to convince pilots that they need to listen carefully to the frequency.

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Original NASA ASRS Text

Title: LESS THAN STANDARD SEPARATION BETWEEN ACR AND CORP ACFT. PLT DEVIATION OR OPERATIONAL ERROR.

Narrative: CORP Y WAS CLBING TO FL310. ACR X WAS AT FL290. CORP Y WAS VECTORED FOR CLB AROUND X. ACR X WAS VECTORED, BUT WOULD NOT LISTEN TO THE FREQ. ACR X WAS CALLED 3 TIMES AND NEVER ACKNOWLEDGED. Y WAS GIVEN AN ADDITIONAL VECTOR TO COMPENSATE FOR X. ACR X ANSWERED THE FOURTH CALL, WAS FINALLY GIVEN A TURN AND DSCNT. ACR X QUESTIONED THE CLRNC. WAS ADVISED THAT HE HAD BEEN CALLED FOR 30 MI. AT THIS POINT, SEP WAS LOST. IF ACFT WAS LISTENING TO FREQ AND HAD TAKEN THE FIRST CLRNC, THERE WOULD HAVE BEEN NO PROB. MY SUGGESTION IS TO CONVINCE PLTS THAT THEY NEED TO LISTEN CAREFULLY TO THE FREQ.

Data retrieved from NASA's ASRS site as of August 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.