Narrative:

We were flying from mco to jfk at night. We were proceeding direct sie VOR, and had been cleared to descend to FL280. As we leveled at FL280, we were aware that we would need to start down soon to make a crossing altitude on the arrival to jfk. We asked for lower, and were given FL270. We were told that we couldn't go lower due to traffic. About 300 ft from leveloff the controller told us to maintain FL270, which was what we were cleared to anyway. We heard the controller tell an air carrier flight to expedite descent. About that time we saw traffic on our TCASII displays, at our altitude, coming at us from about our 1 O'clock position at a high closure rate. TCASII called traffic almost right away. The controller gave the air carrier an immediate 30 degree left turn. Right after that, we got a descent RA, and we notified ATC that we had an RA. He told us to turn 30 degrees left immediately. We acknowledged and told him we were descending by the RA. But somewhere in here the air carrier flight started descending too! He was descending much faster than we were, and at our closest approach (3 mi?) he was 1000 ft below us. After we descended about 700 ft, TCASII gave us a 'clear of conflict' and we started to climb back to FL270. ATC then gave us clearance to continue descent to a lower altitude. The problem we have here is that we followed our TCASII commands to descend, and yet our traffic was descending also. Did he have a descend RA also, or did he have no RA, or did he have a climb RA and ignored it? He apparently had us in sight, so maybe he decided to ignore the RA. We never found out, because the controller was non communicative (maybe a little rattled by the whole thing), and we changed frequencys soon after that.

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Original NASA ASRS Text

Title: MD80 CREW OBTAINS CLRNC TO DSND. CTLR DSNDED ACFT INTO ONCOMING TFC.

Narrative: WE WERE FLYING FROM MCO TO JFK AT NIGHT. WE WERE PROCEEDING DIRECT SIE VOR, AND HAD BEEN CLRED TO DSND TO FL280. AS WE LEVELED AT FL280, WE WERE AWARE THAT WE WOULD NEED TO START DOWN SOON TO MAKE A XING ALT ON THE ARR TO JFK. WE ASKED FOR LOWER, AND WERE GIVEN FL270. WE WERE TOLD THAT WE COULDN'T GO LOWER DUE TO TFC. ABOUT 300 FT FROM LEVELOFF THE CTLR TOLD US TO MAINTAIN FL270, WHICH WAS WHAT WE WERE CLRED TO ANYWAY. WE HEARD THE CTLR TELL AN ACR FLT TO EXPEDITE DSCNT. ABOUT THAT TIME WE SAW TFC ON OUR TCASII DISPLAYS, AT OUR ALT, COMING AT US FROM ABOUT OUR 1 O'CLOCK POS AT A HIGH CLOSURE RATE. TCASII CALLED TFC ALMOST RIGHT AWAY. THE CTLR GAVE THE ACR AN IMMEDIATE 30 DEG L TURN. RIGHT AFTER THAT, WE GOT A DSCNT RA, AND WE NOTIFIED ATC THAT WE HAD AN RA. HE TOLD US TO TURN 30 DEGS L IMMEDIATELY. WE ACKNOWLEDGED AND TOLD HIM WE WERE DSNDING BY THE RA. BUT SOMEWHERE IN HERE THE ACR FLT STARTED DSNDING TOO! HE WAS DSNDING MUCH FASTER THAN WE WERE, AND AT OUR CLOSEST APCH (3 MI?) HE WAS 1000 FT BELOW US. AFTER WE DSNDED ABOUT 700 FT, TCASII GAVE US A 'CLR OF CONFLICT' AND WE STARTED TO CLB BACK TO FL270. ATC THEN GAVE US CLRNC TO CONTINUE DSCNT TO A LOWER ALT. THE PROB WE HAVE HERE IS THAT WE FOLLOWED OUR TCASII COMMANDS TO DSND, AND YET OUR TFC WAS DSNDING ALSO. DID HE HAVE A DSND RA ALSO, OR DID HE HAVE NO RA, OR DID HE HAVE A CLB RA AND IGNORED IT? HE APPARENTLY HAD US IN SIGHT, SO MAYBE HE DECIDED TO IGNORE THE RA. WE NEVER FOUND OUT, BECAUSE THE CTLR WAS NON COMMUNICATIVE (MAYBE A LITTLE RATTLED BY THE WHOLE THING), AND WE CHANGED FREQS SOON AFTER THAT.

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.