Narrative:

Near midair collision. We departed runway 27L from mia. The initial clearance was a turn to 290 degrees, climb to 3000 ft. Departure controller cleared us to 7000 ft prior to reaching 3000 ft. At approximately 3500 ft, we received a TA on the TCASII. Did not see traffic visually. Seconds later, received an RA 'monitor vertical speed.' our rate of climb prior to the RA was well over 3000 FPM. The RA called for approximately 1800 FPM. I reduced vertical speed to comply. We observed the traffic on TCASII to pass directly overhead at an altitude only 600 ft above us. I believe without the TCASII warning, had we continued climbing at our original rate of climb, we would have hit the VFR traffic! TCASII prevented a midair collision.

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Original NASA ASRS Text

Title: B727 CREW HAD A TCASII RA ON CLBOUT AT MIA.

Narrative: NMAC. WE DEPARTED RWY 27L FROM MIA. THE INITIAL CLRNC WAS A TURN TO 290 DEGS, CLB TO 3000 FT. DEP CTLR CLRED US TO 7000 FT PRIOR TO REACHING 3000 FT. AT APPROX 3500 FT, WE RECEIVED A TA ON THE TCASII. DID NOT SEE TFC VISUALLY. SECONDS LATER, RECEIVED AN RA 'MONITOR VERT SPD.' OUR RATE OF CLB PRIOR TO THE RA WAS WELL OVER 3000 FPM. THE RA CALLED FOR APPROX 1800 FPM. I REDUCED VERT SPD TO COMPLY. WE OBSERVED THE TFC ON TCASII TO PASS DIRECTLY OVERHEAD AT AN ALT ONLY 600 FT ABOVE US. I BELIEVE WITHOUT THE TCASII WARNING, HAD WE CONTINUED CLBING AT OUR ORIGINAL RATE OF CLB, WE WOULD HAVE HIT THE VFR TFC! TCASII PREVENTED A MIDAIR COLLISION.

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.