Narrative:

About 2 mins out of aries, tokyo told us to hold east of aries. No altitude, direction or efc time was issued. We held as published at FL210. We heard another aircraft being held at libra at FL210 (about 9 NM southwest of aries). Traffic was very heavy in this area. Other aircraft were having a difficult time understanding the center controller. Many readbacks of altitudes, headings, and airspds. It appeared that center was saturated and they were beginning to lose control of the situation. We entered the hold and completed 1 turn in the hold and were 1/2 way into the second pattern when we noticed on the TCASII another aircraft approaching from the right. TCASII showed the aircraft at FL210. As the aircraft got closer, we reduced the range on the TCASII and it still showed FL210. We made 2 calls to center about the aircraft but no answer from center. We thought possibly the aircraft had been the one holding at libra at FL210 and had overshot his fix. When the TCASII aircraft was within 1 mi of our aircraft, I began a slight climb to FL215. We again called center but received no reply. Radio very congested with other calls. TCASII gave us no alert until I began the climb. It then gave us a TA. About this time we broke into the clear. We saw a B747 off our right, about 1000 ft high and 1/4 mi away. He told center he had an alert and was climbing. I don't believe center replied. We descended down to FL210. The B747 continued over aries and to cue VOR. Tokyo center then mentioned something about holding at aries to the B747. He replied that they had not been given a hold at aries.

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Original NASA ASRS Text

Title: LOSS OF SEPARATION BTWN AN ACR MD11 AND AN ACR B747 AT FL210.

Narrative: ABOUT 2 MINS OUT OF ARIES, TOKYO TOLD US TO HOLD E OF ARIES. NO ALT, DIRECTION OR EFC TIME WAS ISSUED. WE HELD AS PUBLISHED AT FL210. WE HEARD ANOTHER ACFT BEING HELD AT LIBRA AT FL210 (ABOUT 9 NM SW OF ARIES). TFC WAS VERY HVY IN THIS AREA. OTHER ACFT WERE HAVING A DIFFICULT TIME UNDERSTANDING THE CTR CTLR. MANY READBACKS OF ALTS, HDGS, AND AIRSPDS. IT APPEARED THAT CTR WAS SATURATED AND THEY WERE BEGINNING TO LOSE CTL OF THE SIT. WE ENTERED THE HOLD AND COMPLETED 1 TURN IN THE HOLD AND WERE 1/2 WAY INTO THE SECOND PATTERN WHEN WE NOTICED ON THE TCASII ANOTHER ACFT APCHING FROM THE R. TCASII SHOWED THE ACFT AT FL210. AS THE ACFT GOT CLOSER, WE REDUCED THE RANGE ON THE TCASII AND IT STILL SHOWED FL210. WE MADE 2 CALLS TO CTR ABOUT THE ACFT BUT NO ANSWER FROM CTR. WE THOUGHT POSSIBLY THE ACFT HAD BEEN THE ONE HOLDING AT LIBRA AT FL210 AND HAD OVERSHOT HIS FIX. WHEN THE TCASII ACFT WAS WITHIN 1 MI OF OUR ACFT, I BEGAN A SLIGHT CLB TO FL215. WE AGAIN CALLED CTR BUT RECEIVED NO REPLY. RADIO VERY CONGESTED WITH OTHER CALLS. TCASII GAVE US NO ALERT UNTIL I BEGAN THE CLB. IT THEN GAVE US A TA. ABOUT THIS TIME WE BROKE INTO THE CLR. WE SAW A B747 OFF OUR R, ABOUT 1000 FT HIGH AND 1/4 MI AWAY. HE TOLD CTR HE HAD AN ALERT AND WAS CLBING. I DON'T BELIEVE CTR REPLIED. WE DSNDED DOWN TO FL210. THE B747 CONTINUED OVER ARIES AND TO CUE VOR. TOKYO CTR THEN MENTIONED SOMETHING ABOUT HOLDING AT ARIES TO THE B747. HE REPLIED THAT THEY HAD NOT BEEN GIVEN A HOLD AT ARIES.

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.