Narrative:

On approach at cle runway 5R ILS 10 NM 'cleared to 3000 ft until intercepting GS, cleared for approach.' approach advised us of traffic right to left below us at 2500 ft. We were in IMC. The TCASII picked up our traffic at our 3 O'clock position. I first recalled it as being a red circle at minus 400 ft and a traffic announcement, then it continued to climb minus 300 ft and (I think) minus 200 ft. At that time we received a climb command in excess of 1000 FPM which we complied with. At 3600 ft we received a 'clear of conflict.' we completed our climb at 3800 ft and advised ATC (cle approach) who acknowledged us and reaffirmed that we were still cleared for the approach. We completed a normal approach and landing. We did call approach after landing and they advised us that the traffic was on a VFR flight plan and that their equipment indicated at least a 300 ft separation with no collision alert. Supplemental information from acn 236044: traffic had a perpendicular flight path and appeared to climb to 300 ft below our level. Could not contact ATC as frequency was very congested. (I observed vertical separation at 200 ft during the RA as climb was initiated.) ATC was contacted by the captain after landing. We were advised that the traffic was on a VFR flight plan and that radar indicated at least 300 ft separation and no collision alert on his equipment.

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Original NASA ASRS Text

Title: AN ACR MLG CLBED IN RESPONSE TO A TCASII COMMAND AT NIGHT IN IMC.

Narrative: ON APCH AT CLE RWY 5R ILS 10 NM 'CLRED TO 3000 FT UNTIL INTERCEPTING GS, CLRED FOR APCH.' APCH ADVISED US OF TFC R TO L BELOW US AT 2500 FT. WE WERE IN IMC. THE TCASII PICKED UP OUR TFC AT OUR 3 O'CLOCK POS. I FIRST RECALLED IT AS BEING A RED CIRCLE AT MINUS 400 FT AND A TFC ANNOUNCEMENT, THEN IT CONTINUED TO CLB MINUS 300 FT AND (I THINK) MINUS 200 FT. AT THAT TIME WE RECEIVED A CLB COMMAND IN EXCESS OF 1000 FPM WHICH WE COMPLIED WITH. AT 3600 FT WE RECEIVED A 'CLR OF CONFLICT.' WE COMPLETED OUR CLB AT 3800 FT AND ADVISED ATC (CLE APCH) WHO ACKNOWLEDGED US AND REAFFIRMED THAT WE WERE STILL CLRED FOR THE APCH. WE COMPLETED A NORMAL APCH AND LNDG. WE DID CALL APCH AFTER LNDG AND THEY ADVISED US THAT THE TFC WAS ON A VFR FLT PLAN AND THAT THEIR EQUIP INDICATED AT LEAST A 300 FT SEPARATION WITH NO COLLISION ALERT. SUPPLEMENTAL INFO FROM ACN 236044: TFC HAD A PERPENDICULAR FLT PATH AND APPEARED TO CLB TO 300 FT BELOW OUR LEVEL. COULD NOT CONTACT ATC AS FREQ WAS VERY CONGESTED. (I OBSERVED VERT SEPARATION AT 200 FT DURING THE RA AS CLB WAS INITIATED.) ATC WAS CONTACTED BY THE CAPT AFTER LNDG. WE WERE ADVISED THAT THE TFC WAS ON A VFR FLT PLAN AND THAT RADAR INDICATED AT LEAST 300 FT SEPARATION AND NO COLLISION ALERT ON HIS EQUIP.

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.