Narrative:

En route from denver to dallas ft worth (dfw), we were descended from FL370 to FL330 as we approached amarillo. ATC advised after reaching FL330 we were cleared to cross 40 NM northwest of bridgeport VOR at FL240 on the boids 2 arrival to dfw. We planned to begin our descent 25 NM northwest of wichita falls. At about 80 NM out of wichita falls, center pointed out traffic in the opposite direction at our 10 O'clock position, level at FL310. We idented the traffic visually and so advised ATC. Very shortly after that, as the traffic passed off our left side, ATC asked us our altitude. We were still level at FL330 and so noted it on all 3 altimeters. We additionally noticed the TCASII indicating our 9 O'clock traffic as passing 5 mi to our left and the altitude difference indicated 1900 below us. Center then asked us to verify our altitude and again we rechked all altimeters, 29.92 settings and transponder altitude reporting switch on. We again confirmed for ATC that we were at FL330 level. We were advised that the center's equipment had intermittently given off a conflict alert. Center did not sound too concerned about the situation. I was however aware of the seriousness of such encounters with other pilots and controllers. We began our descent to FL240 about 25 mi later and was reassured of no problem existing.

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Original NASA ASRS Text

Title: LTSS BTWN OPPOSITE DIRECTION ACR ACFT AT CRUISE ALT E OF AMA.

Narrative: ENRTE FROM DENVER TO DALLAS FT WORTH (DFW), WE WERE DSNDED FROM FL370 TO FL330 AS WE APCHED AMARILLO. ATC ADVISED AFTER REACHING FL330 WE WERE CLRED TO CROSS 40 NM NW OF BRIDGEPORT VOR AT FL240 ON THE BOIDS 2 ARR TO DFW. WE PLANNED TO BEGIN OUR DSCNT 25 NM NW OF WICHITA FALLS. AT ABOUT 80 NM OUT OF WICHITA FALLS, CENTER POINTED OUT TFC IN THE OPPOSITE DIRECTION AT OUR 10 O'CLOCK POS, LEVEL AT FL310. WE IDENTED THE TFC VISUALLY AND SO ADVISED ATC. VERY SHORTLY AFTER THAT, AS THE TFC PASSED OFF OUR L SIDE, ATC ASKED US OUR ALT. WE WERE STILL LEVEL AT FL330 AND SO NOTED IT ON ALL 3 ALTIMETERS. WE ADDITIONALLY NOTICED THE TCASII INDICATING OUR 9 O'CLOCK TFC AS PASSING 5 MI TO OUR L AND THE ALT DIFFERENCE INDICATED 1900 BELOW US. CENTER THEN ASKED US TO VERIFY OUR ALT AND AGAIN WE RECHKED ALL ALTIMETERS, 29.92 SETTINGS AND TRANSPONDER ALT RPTING SWITCH ON. WE AGAIN CONFIRMED FOR ATC THAT WE WERE AT FL330 LEVEL. WE WERE ADVISED THAT THE CENTER'S EQUIP HAD INTERMITTENTLY GIVEN OFF A CONFLICT ALERT. CENTER DID NOT SOUND TOO CONCERNED ABOUT THE SITUATION. I WAS HOWEVER AWARE OF THE SERIOUSNESS OF SUCH ENCOUNTERS WITH OTHER PLTS AND CTLRS. WE BEGAN OUR DSCNT TO FL240 ABOUT 25 MI LATER AND WAS REASSURED OF NO PROBLEM EXISTING.

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.