Narrative:

In contact with long island approach control, following radar vectors at 11000 ft, we were cleared to descend to 5000 ft. This situation was made more difficult because the aircraft automatic pressurization controller had been on MEL since jun/xx/94. The manual controller was the 'lollipop' type. It requires a lot of attention with each power change. As I retarded the throttles, the first officer was inside the aircraft dealing with the pressurization. We noticed a TA at our 12 O'clock position. The first officer questioned the controller about the traffic. By this time, we were already descending through about 10000 ft. The controller did not respond to us. At about 10000 ft, we received an RA (monitor vertical descent). At this time, we had approximately 1500 FPM descent. Aircraft descent was stopped at approximately 9700 ft then climbed to approximately 10200 ft. At the bottom of the descent, both the first officer and myself had visual contact with the traffic (which was 5 high-performance south/east aircraft trailing smoke) in formation! We questioned the controller again about the traffic, he hesitated, then said only 'confirm traffic is at 9000 ft.' that was the only mention of the traffic to us by ATC. We never did find out why we were cleared to descend through the traffic. Must have been a severe mix-up. TCASII saved us! We reported the event to the controller and he never said another word about it.

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Original NASA ASRS Text

Title: FLC OF MLG STOPPED DSCNT AND CLBED IN RESPONSE TO A TCASII RA.

Narrative: IN CONTACT WITH LONG ISLAND APCH CTL, FOLLOWING RADAR VECTORS AT 11000 FT, WE WERE CLRED TO DSND TO 5000 FT. THIS SIT WAS MADE MORE DIFFICULT BECAUSE THE ACFT AUTO PRESSURIZATION CTLR HAD BEEN ON MEL SINCE JUN/XX/94. THE MANUAL CTLR WAS THE 'LOLLIPOP' TYPE. IT REQUIRES A LOT OF ATTN WITH EACH PWR CHANGE. AS I RETARDED THE THROTTLES, THE FO WAS INSIDE THE ACFT DEALING WITH THE PRESSURIZATION. WE NOTICED A TA AT OUR 12 O'CLOCK POS. THE FO QUESTIONED THE CTLR ABOUT THE TFC. BY THIS TIME, WE WERE ALREADY DSNDING THROUGH ABOUT 10000 FT. THE CTLR DID NOT RESPOND TO US. AT ABOUT 10000 FT, WE RECEIVED AN RA (MONITOR VERT DSCNT). AT THIS TIME, WE HAD APPROX 1500 FPM DSCNT. ACFT DSCNT WAS STOPPED AT APPROX 9700 FT THEN CLBED TO APPROX 10200 FT. AT THE BOTTOM OF THE DSCNT, BOTH THE FO AND MYSELF HAD VISUAL CONTACT WITH THE TFC (WHICH WAS 5 HIGH-PERFORMANCE S/E ACFT TRAILING SMOKE) IN FORMATION! WE QUESTIONED THE CTLR AGAIN ABOUT THE TFC, HE HESITATED, THEN SAID ONLY 'CONFIRM TFC IS AT 9000 FT.' THAT WAS THE ONLY MENTION OF THE TFC TO US BY ATC. WE NEVER DID FIND OUT WHY WE WERE CLRED TO DSND THROUGH THE TFC. MUST HAVE BEEN A SEVERE MIX-UP. TCASII SAVED US! WE RPTED THE EVENT TO THE CTLR AND HE NEVER SAID ANOTHER WORD ABOUT IT.

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.