Narrative:

While being cleared for a visual approach to mem we had just been given a frequency change to tower. Prior to checking in, we received a TCASII TA, followed by an RA to 'climb.' while climbing, we received a second RA to 'descend, descend now.' after traffic passed, we landed at mem. The first TA showed an altitude of 2300 ft and we estimate an approximately vertical separation of 300-500 ft. The second RA we actually saw the aircraft on the pushover pass overhead and off to the right at approximately 500 ft vertical separation. ATC was advised and contacted on the phone after landing. The ATC supervisor had started looking into the situation. The first RA was with an aircraft that was VFR and not being worked by ATC and was just outside the class B airspace and was going to an uncontrolled airport. The second RA/conflict was with an aircraft that was being worked by ATC and was making a visual descent into the same airport that the first aircraft was going to. ATC stated he had us in sight and was maintaining a visual clearance. The problem with this incident is that with only vertical guidance for the resolution it causes the second resolution.

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Original NASA ASRS Text

Title: AIRBORNE CONFLICT BTWN THE RPTR IN ACR MDT DSNDING TO LAND AT AN ARPT IN CLASS B AIRSPACE AND 2 OTHER UNKNOWN ACFT DSNDING TO GO INTO AN UNCTLED ARPT OUTSIDE OF CLASS B AIRSPACE. THE FIRST ENCOUNTER WAS NOT VISUALLY OBSERVED BUT PRODUCED A TCASII RA AS AN NMAC, AND NOT UNDER ATC CTL. THE SECOND WAS CTLED AND WAS VISUALLY OBSERVED AS IT WENT BY. RPTR TOOK EVASIVE ACTION BY FIRST CLBING AND THEN DSNDING.

Narrative: WHILE BEING CLRED FOR A VISUAL APCH TO MEM WE HAD JUST BEEN GIVEN A FREQ CHANGE TO TWR. PRIOR TO CHKING IN, WE RECEIVED A TCASII TA, FOLLOWED BY AN RA TO 'CLB.' WHILE CLBING, WE RECEIVED A SECOND RA TO 'DSND, DSND NOW.' AFTER TFC PASSED, WE LANDED AT MEM. THE FIRST TA SHOWED AN ALT OF 2300 FT AND WE ESTIMATE AN APPROX VERT SEPARATION OF 300-500 FT. THE SECOND RA WE ACTUALLY SAW THE ACFT ON THE PUSHOVER PASS OVERHEAD AND OFF TO THE R AT APPROX 500 FT VERT SEPARATION. ATC WAS ADVISED AND CONTACTED ON THE PHONE AFTER LNDG. THE ATC SUPVR HAD STARTED LOOKING INTO THE SIT. THE FIRST RA WAS WITH AN ACFT THAT WAS VFR AND NOT BEING WORKED BY ATC AND WAS JUST OUTSIDE THE CLASS B AIRSPACE AND WAS GOING TO AN UNCTLED ARPT. THE SECOND RA/CONFLICT WAS WITH AN ACFT THAT WAS BEING WORKED BY ATC AND WAS MAKING A VISUAL DSCNT INTO THE SAME ARPT THAT THE FIRST ACFT WAS GOING TO. ATC STATED HE HAD US IN SIGHT AND WAS MAINTAINING A VISUAL CLRNC. THE PROB WITH THIS INCIDENT IS THAT WITH ONLY VERT GUIDANCE FOR THE RESOLUTION IT CAUSES THE SECOND RESOLUTION.

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.