Narrative:

Departing sjo, ramon departure, runway 07, at 3 DME in moderate rain. Received TCASII TA (yellow DOT) with no altitude. Target was directly in our flight path at less than 1 mi. We were climbing at maximum power. Light load. Visibility restr due to rain. First officer found traffic as we were about to climb into him. Appeared to be a twin piper less than 500 ft vertical separation. Captain was PF. I leveled aircraft and increased angle of bank to 45 degrees in order to clear target and avoid thunderstorm. Sjo departure at first said they had no traffic there, then a moment later told us there was a piper in our path. Airport had recently opened after being closed for thunderstorm for about 20 mins. TCASII and first officer's quick sighting definitely saved us. From left seat, target was out of sight above the view of the windscreen.

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Original NASA ASRS Text

Title: AN ACR B757 CAPT RPTS THAT HE HAD AN NMAC DEPARTING SJO.

Narrative: DEPARTING SJO, RAMON DEP, RWY 07, AT 3 DME IN MODERATE RAIN. RECEIVED TCASII TA (YELLOW DOT) WITH NO ALT. TARGET WAS DIRECTLY IN OUR FLT PATH AT LESS THAN 1 MI. WE WERE CLBING AT MAX PWR. LIGHT LOAD. VISIBILITY RESTR DUE TO RAIN. FO FOUND TFC AS WE WERE ABOUT TO CLB INTO HIM. APPEARED TO BE A TWIN PIPER LESS THAN 500 FT VERT SEPARATION. CAPT WAS PF. I LEVELED ACFT AND INCREASED ANGLE OF BANK TO 45 DEGS IN ORDER TO CLR TARGET AND AVOID TSTM. SJO DEP AT FIRST SAID THEY HAD NO TFC THERE, THEN A MOMENT LATER TOLD US THERE WAS A PIPER IN OUR PATH. ARPT HAD RECENTLY OPENED AFTER BEING CLOSED FOR TSTM FOR ABOUT 20 MINS. TCASII AND FO'S QUICK SIGHTING DEFINITELY SAVED US. FROM L SEAT, TARGET WAS OUT OF SIGHT ABOVE THE VIEW OF THE WINDSCREEN.

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.