Narrative:

After departing stl, at approximately 5-10 mi north of stl, our aircraft encountered a TCASII proximate traffic symbol at our 2 O'clock and less than 5 NM from our aircraft, approaching. The target showed to be 400 ft below our position and climbing. Immediately as the traffic popped up as a blue solid diamond it went to an amber circle and the synthesized voice called out the TA, 'traffic, traffic.' as before, as quick as the traffic became an amber advisory, it was a red RA. The RA sounded as 'climb, climb.' our aircraft was on a 030 degree heading with a climb clearance to 15000 ft MSL. At all times we were IMC, and no TA was given by stl departure (119.15 MHZ). I, the captain, was hand flying the aircraft and our vertical speed was already at 3000 FPM and 240 KTS passing 5000 ft MSL when the RA was given. As we responded to the RA, our vertical speed exceeded 5000 FPM. As god is my witness I thought there would be a collision, we could do nothing else but watch the horror unfold. The solid red square TCASII symbol passed our immediate position as a double zero, indicating same altitude. I held the control wheel, watching the airspeed approach 200 KTS and waited for the impact. When the RA cleared, the traffic had passed to our 7 O'clock position and it turned back into a solid blue diamond and disappeared. After returning the aircraft to the proper climb profile, we informed the controller of what had transpired and asked if he showed any traffic near us and he assured us there was nothing. I personally explained the situation to the passenger, and we continued to cincinnati. Total time for this incident to transpire was 15-20 seconds. Callback conversation with reporter revealed the following information: reporter captain immediately questioned the controller about traffic and the controller had no targets. WX was IMC so flight crew was unable to visually acquire the target. Reporter says that at first the target looked suspect (false), but then when it was closing and climbing it looked very real. Reporter had a TCASII questionnaire that he had received from his company and he filled it out about this incident. He received a callback from the manufacturer of the TCASII who told him they were soon coming out with a phase 4 TCASII which should have less problems with false targets. Reporter also sent a report to pilot group who is following it up by pulling the tapes at stl to be certain that there was no target there.

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Original NASA ASRS Text

Title: CL65 ACFT IN CLB, IMC, RECEIVED TCASII RA AND FLC EVADED WITH HIGH CLB RATE.

Narrative: AFTER DEPARTING STL, AT APPROX 5-10 MI N OF STL, OUR ACFT ENCOUNTERED A TCASII PROXIMATE TFC SYMBOL AT OUR 2 O'CLOCK AND LESS THAN 5 NM FROM OUR ACFT, APCHING. THE TARGET SHOWED TO BE 400 FT BELOW OUR POS AND CLBING. IMMEDIATELY AS THE TFC POPPED UP AS A BLUE SOLID DIAMOND IT WENT TO AN AMBER CIRCLE AND THE SYNTHESIZED VOICE CALLED OUT THE TA, 'TFC, TFC.' AS BEFORE, AS QUICK AS THE TFC BECAME AN AMBER ADVISORY, IT WAS A RED RA. THE RA SOUNDED AS 'CLB, CLB.' OUR ACFT WAS ON A 030 DEG HDG WITH A CLB CLRNC TO 15000 FT MSL. AT ALL TIMES WE WERE IMC, AND NO TA WAS GIVEN BY STL DEP (119.15 MHZ). I, THE CAPT, WAS HAND FLYING THE ACFT AND OUR VERT SPD WAS ALREADY AT 3000 FPM AND 240 KTS PASSING 5000 FT MSL WHEN THE RA WAS GIVEN. AS WE RESPONDED TO THE RA, OUR VERT SPD EXCEEDED 5000 FPM. AS GOD IS MY WITNESS I THOUGHT THERE WOULD BE A COLLISION, WE COULD DO NOTHING ELSE BUT WATCH THE HORROR UNFOLD. THE SOLID RED SQUARE TCASII SYMBOL PASSED OUR IMMEDIATE POS AS A DOUBLE ZERO, INDICATING SAME ALT. I HELD THE CTL WHEEL, WATCHING THE AIRSPD APCH 200 KTS AND WAITED FOR THE IMPACT. WHEN THE RA CLRED, THE TFC HAD PASSED TO OUR 7 O'CLOCK POS AND IT TURNED BACK INTO A SOLID BLUE DIAMOND AND DISAPPEARED. AFTER RETURNING THE ACFT TO THE PROPER CLB PROFILE, WE INFORMED THE CTLR OF WHAT HAD TRANSPIRED AND ASKED IF HE SHOWED ANY TFC NEAR US AND HE ASSURED US THERE WAS NOTHING. I PERSONALLY EXPLAINED THE SIT TO THE PAX, AND WE CONTINUED TO CINCINNATI. TOTAL TIME FOR THIS INCIDENT TO TRANSPIRE WAS 15-20 SECONDS. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR CAPT IMMEDIATELY QUESTIONED THE CTLR ABOUT TFC AND THE CTLR HAD NO TARGETS. WX WAS IMC SO FLC WAS UNABLE TO VISUALLY ACQUIRE THE TARGET. RPTR SAYS THAT AT FIRST THE TARGET LOOKED SUSPECT (FALSE), BUT THEN WHEN IT WAS CLOSING AND CLBING IT LOOKED VERY REAL. RPTR HAD A TCASII QUESTIONNAIRE THAT HE HAD RECEIVED FROM HIS COMPANY AND HE FILLED IT OUT ABOUT THIS INCIDENT. HE RECEIVED A CALLBACK FROM THE MANUFACTURER OF THE TCASII WHO TOLD HIM THEY WERE SOON COMING OUT WITH A PHASE 4 TCASII WHICH SHOULD HAVE LESS PROBS WITH FALSE TARGETS. RPTR ALSO SENT A RPT TO PLT GROUP WHO IS FOLLOWING IT UP BY PULLING THE TAPES AT STL TO BE CERTAIN THAT THERE WAS NO TARGET THERE.

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.