Narrative:

ATC facility: pty departure control. Location: pty 090 degree radial, 20 DME. Assigned 090 degree heading, climbing to 5000 ft. Requested turn to 060 degrees for WX, approved as we leveled at 5000 ft. Cautioned about VFR traffic at 11 O'clock position at 5500 ft. WX IFR with dark clouds from nearby 'circuit breaker' visibility reduced. With aircraft inside 10 mi we got a yellow TCASII alert that changed rapidly to a red RA and 'monitor vertical speed.' the TCASII target was descending through 5300 ft when we received a 'descend now' warning with a command to 2000 ft down. The captain spotted the aircraft on the left about 2 mi abeam as we descended from 5000 ft to 4600 ft. It was a C172 type aircraft. The traffic descended through our altitude. They stated that the traffic was at 5500 ft. We stated their true position. They then responded that the traffic had descended with us in sight and had not flown below us. The TCASII alert showed that they had. We climbed back to 5000 ft and continued en route.

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Original NASA ASRS Text

Title: A DSNDING VFR C172 CONFLICTS WITH A DEP, CLBING B757 OUT OF MPTO, PANAMA CITY, FO.

Narrative: ATC FACILITY: PTY DEP CTL. LOCATION: PTY 090 DEG RADIAL, 20 DME. ASSIGNED 090 DEG HDG, CLBING TO 5000 FT. REQUESTED TURN TO 060 DEGS FOR WX, APPROVED AS WE LEVELED AT 5000 FT. CAUTIONED ABOUT VFR TFC AT 11 O'CLOCK POS AT 5500 FT. WX IFR WITH DARK CLOUDS FROM NEARBY 'CB' VISIBILITY REDUCED. WITH ACFT INSIDE 10 MI WE GOT A YELLOW TCASII ALERT THAT CHANGED RAPIDLY TO A RED RA AND 'MONITOR VERT SPD.' THE TCASII TARGET WAS DSNDING THROUGH 5300 FT WHEN WE RECEIVED A 'DSND NOW' WARNING WITH A COMMAND TO 2000 FT DOWN. THE CAPT SPOTTED THE ACFT ON THE L ABOUT 2 MI ABEAM AS WE DSNDED FROM 5000 FT TO 4600 FT. IT WAS A C172 TYPE ACFT. THE TFC DSNDED THROUGH OUR ALT. THEY STATED THAT THE TFC WAS AT 5500 FT. WE STATED THEIR TRUE POS. THEY THEN RESPONDED THAT THE TFC HAD DSNDED WITH US IN SIGHT AND HAD NOT FLOWN BELOW US. THE TCASII ALERT SHOWED THAT THEY HAD. WE CLBED BACK TO 5000 FT AND CONTINUED ENRTE.

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.