Narrative:

We took off from lgb runway 30, cleared to climb to 1500 ft, left turn to heading 180 degrees, then continue climb to 3000 ft. It was the first officer's leg. After turning to 180 degrees, we were switched to departure control. They cleared us to 4000 ft. At some point after passing around 2500 ft, we got a TA for some traffic at approximately 1230 O'clock and 800 ft above us. I told the first officer to expect an RA, and we immediately got one, first to 'monitor vertical speed,' which almost immediately changed to 'descend, descend now.' the RA called for a large pitch change from our climb rate of more than 2000 FPM to a large rate of descent. As our vertical separation closed to 100 ft, my first officer spotted the traffic at about 1 O'clock position. We had stopped our climb and started descending. I didn't see the traffic, but it was close to us, even on the 2 1/2 mi scale on my navigation display. I would estimate that we got to within about 1 mi of the traffic. Just as we passed the closest point of approach, my first officer said he saw the traffic (which he believed to be a piper cherokee) sharply pull up and to the left to pass behind us. It was at this point that ATC called us with a TA for the first time. I advised him that we were already responding to an RA and would return to assigned altitude when able. Since we had an altitude displayed for the traffic throughout this event, I have to believe he was squawking mode 3C, so I can't explain ATC's failure to call the traffic, much less clearing us to climb into it.

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Original NASA ASRS Text

Title: A B737 CAPT RPTED AN NMAC DURING CLBOUT FROM LGB.

Narrative: WE TOOK OFF FROM LGB RWY 30, CLRED TO CLB TO 1500 FT, L TURN TO HDG 180 DEGS, THEN CONTINUE CLB TO 3000 FT. IT WAS THE FO'S LEG. AFTER TURNING TO 180 DEGS, WE WERE SWITCHED TO DEP CTL. THEY CLRED US TO 4000 FT. AT SOME POINT AFTER PASSING AROUND 2500 FT, WE GOT A TA FOR SOME TFC AT APPROX 1230 O'CLOCK AND 800 FT ABOVE US. I TOLD THE FO TO EXPECT AN RA, AND WE IMMEDIATELY GOT ONE, FIRST TO 'MONITOR VERT SPD,' WHICH ALMOST IMMEDIATELY CHANGED TO 'DSND, DSND NOW.' THE RA CALLED FOR A LARGE PITCH CHANGE FROM OUR CLB RATE OF MORE THAN 2000 FPM TO A LARGE RATE OF DSCNT. AS OUR VERT SEPARATION CLOSED TO 100 FT, MY FO SPOTTED THE TFC AT ABOUT 1 O'CLOCK POS. WE HAD STOPPED OUR CLB AND STARTED DSNDING. I DIDN'T SEE THE TFC, BUT IT WAS CLOSE TO US, EVEN ON THE 2 1/2 MI SCALE ON MY NAV DISPLAY. I WOULD ESTIMATE THAT WE GOT TO WITHIN ABOUT 1 MI OF THE TFC. JUST AS WE PASSED THE CLOSEST POINT OF APCH, MY FO SAID HE SAW THE TFC (WHICH HE BELIEVED TO BE A PIPER CHEROKEE) SHARPLY PULL UP AND TO THE L TO PASS BEHIND US. IT WAS AT THIS POINT THAT ATC CALLED US WITH A TA FOR THE FIRST TIME. I ADVISED HIM THAT WE WERE ALREADY RESPONDING TO AN RA AND WOULD RETURN TO ASSIGNED ALT WHEN ABLE. SINCE WE HAD AN ALT DISPLAYED FOR THE TFC THROUGHOUT THIS EVENT, I HAVE TO BELIEVE HE WAS SQUAWKING MODE 3C, SO I CAN'T EXPLAIN ATC'S FAILURE TO CALL THE TFC, MUCH LESS CLRING US TO CLB INTO IT.

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.