Narrative:

During departure from msp international airport we were on a vector, heading 100 degrees climbing to 10000 ft MSL. As we passed 9000 ft departure control advised us of VFR traffic, a cherokee, at our 11 O'clock, approximately 8 mi at 10500. Departure control then advised the cherokee of us -- a dc-9 passing 9000 ft for 10000 ft at his 1 O'clock. As we leveled at 10000 ft our TCASII showed the cherokee at 11 O'clock, 5 mi, and plus 600 ft. TCASII advised us to monitor vertical speed and showed a red arc from '0' FPM to 2500 FPM climb on our ivsi. By now we had the cherokee visually and advised departure control that we did. As the cherokee approached our 12 O'clock, we noticed that the cherokee appeared to be at our altitude (10000 MSL) and not at 10500 ft. At that moment, the cherokee entered the TCASII warning area and the TCASII gave a RA do descend. A moment prior to the TCASII RA, we had begun our own evasive maneuver by starting a left turn to avoid the cherokee. Our evasive action resulted in a slight heading deviation to the left and a descent of approximately 200 ft. We narrowly missed the cherokee as he descended through our altitude. Approximately miss distance was only 200 ft horizontally and less than 200 ft vertically. I believe that, if we had not maneuvered, we would have had a mid-air collision. Shortly after our evasive action, our TCASII advised 'clear of conflict.' we visually confirmed that and we recovered to 10000 ft MSL and heading 100 degrees. Supplemental information from acn 268961: I asked minneapolis approach: 'this is call sign, does my traffic have me?' I received no response. I called again 'call sign, does my traffic have me?' and again I received no response. At this point the airliner looked like it was at my altitude directly at 3 O'clock several mi away on a collision course with me and I had no indication that ATC or the flight crew of the airliner had any indication of the situation. I therefore immediately descended to try to avoid the airliner. The airliner passed behind me by perhaps 1000 ft at approximately the same altitude. Afterward, ATC said that in the original situation he had provided 500 ft of vertical separation between the airliner and me.

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Original NASA ASRS Text

Title: VFR SMA DSNDED INTO ACR TFC LEVELLING 500 FT BELOW.

Narrative: DURING DEP FROM MSP INTL ARPT WE WERE ON A VECTOR, HDG 100 DEGS CLBING TO 10000 FT MSL. AS WE PASSED 9000 FT DEP CTL ADVISED US OF VFR TFC, A CHEROKEE, AT OUR 11 O'CLOCK, APPROX 8 MI AT 10500. DEP CTL THEN ADVISED THE CHEROKEE OF US -- A DC-9 PASSING 9000 FT FOR 10000 FT AT HIS 1 O'CLOCK. AS WE LEVELED AT 10000 FT OUR TCASII SHOWED THE CHEROKEE AT 11 O'CLOCK, 5 MI, AND PLUS 600 FT. TCASII ADVISED US TO MONITOR VERT SPD AND SHOWED A RED ARC FROM '0' FPM TO 2500 FPM CLB ON OUR IVSI. BY NOW WE HAD THE CHEROKEE VISUALLY AND ADVISED DEP CTL THAT WE DID. AS THE CHEROKEE APCHED OUR 12 O'CLOCK, WE NOTICED THAT THE CHEROKEE APPEARED TO BE AT OUR ALT (10000 MSL) AND NOT AT 10500 FT. AT THAT MOMENT, THE CHEROKEE ENTERED THE TCASII WARNING AREA AND THE TCASII GAVE A RA DO DSND. A MOMENT PRIOR TO THE TCASII RA, WE HAD BEGUN OUR OWN EVASIVE MANEUVER BY STARTING A L TURN TO AVOID THE CHEROKEE. OUR EVASIVE ACTION RESULTED IN A SLIGHT HDG DEV TO THE LEFT AND A DSCNT OF APPROX 200 FT. WE NARROWLY MISSED THE CHEROKEE AS HE DSNDED THROUGH OUR ALT. APPROX MISS DISTANCE WAS ONLY 200 FT HORIZLY AND LESS THAN 200 FT VERTLY. I BELIEVE THAT, IF WE HAD NOT MANEUVERED, WE WOULD HAVE HAD A MID-AIR COLLISION. SHORTLY AFTER OUR EVASIVE ACTION, OUR TCASII ADVISED 'CLEAR OF CONFLICT.' WE VISUALLY CONFIRMED THAT AND WE RECOVERED TO 10000 FT MSL AND HDG 100 DEGS. SUPPLEMENTAL INFO FROM ACN 268961: I ASKED MINNEAPOLIS APCH: 'THIS IS CALL SIGN, DOES MY TFC HAVE ME?' I RECEIVED NO RESPONSE. I CALLED AGAIN 'CALL SIGN, DOES MY TFC HAVE ME?' AND AGAIN I RECEIVED NO RESPONSE. AT THIS POINT THE AIRLINER LOOKED LIKE IT WAS AT MY ALT DIRECTLY AT 3 O'CLOCK SEVERAL MI AWAY ON A COLLISION COURSE WITH ME AND I HAD NO INDICATION THAT ATC OR THE FLC OF THE AIRLINER HAD ANY INDICATION OF THE SIT. I THEREFORE IMMEDIATELY DSNDED TO TRY TO AVOID THE AIRLINER. THE AIRLINER PASSED BEHIND ME BY PERHAPS 1000 FT AT APPROX THE SAME ALT. AFTERWARD, ATC SAID THAT IN THE ORIGINAL SIT HE HAD PROVIDED 500 FT OF VERT SEPARATION BTWN THE AIRLINER AND ME.

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.