Narrative:

We departed ont on the pomona 6 SID. Socal cleared us direct to pomona, comply with restrs (pomona at or below 8000 ft) and advised us of small airplane traffic over pomona at 8500 ft VFR. We had the traffic on TCASII but not visually. Socal then advised us of small airplane traffic west of pomona eastbound at 5500 ft. We also had him on TCASII but not visually. In the vicinity of pomona VOR, climbing through approximately 5300 ft, a TCASII RA told us to descend due to the 8500 ft traffic. The copilot initiated the descent, reaching about 5500 ft before descending. We advised socal that we were descending due to a TCASII RA. Socal said 'don't descend -- you are descending back into him.' the conflicting aircraft apparently had us in sight, but took no action to prevent or avoid the conflict. About the time socal finished telling us not to descend, we were about 5100 ft and the TCASII descend warning had terminated. We continued the climb on the SID with no further conflict. The closest point of approach appeared to be approximately 2.5 mi lateral separation, 0 vertical. My guess is that TCASII gave us a descend advisory rather than climb due to the 8500 ft traffic above.

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Original NASA ASRS Text

Title: AN ACR B737 HAD AN ENCOUNTER WITH 2 VFR SMA'S OVER THE POM VOR. WX FACTOR SEVERE VMC CAUSING A TFC JAM OVER POM.

Narrative: WE DEPARTED ONT ON THE POMONA 6 SID. SOCAL CLRED US DIRECT TO POMONA, COMPLY WITH RESTRS (POMONA AT OR BELOW 8000 FT) AND ADVISED US OF SMALL AIRPLANE TFC OVER POMONA AT 8500 FT VFR. WE HAD THE TFC ON TCASII BUT NOT VISUALLY. SOCAL THEN ADVISED US OF SMALL AIRPLANE TFC W OF POMONA EBOUND AT 5500 FT. WE ALSO HAD HIM ON TCASII BUT NOT VISUALLY. IN THE VICINITY OF POMONA VOR, CLBING THROUGH APPROX 5300 FT, A TCASII RA TOLD US TO DSND DUE TO THE 8500 FT TFC. THE COPLT INITIATED THE DSCNT, REACHING ABOUT 5500 FT BEFORE DSNDING. WE ADVISED SOCAL THAT WE WERE DSNDING DUE TO A TCASII RA. SOCAL SAID 'DON'T DSND -- YOU ARE DSNDING BACK INTO HIM.' THE CONFLICTING ACFT APPARENTLY HAD US IN SIGHT, BUT TOOK NO ACTION TO PREVENT OR AVOID THE CONFLICT. ABOUT THE TIME SOCAL FINISHED TELLING US NOT TO DSND, WE WERE ABOUT 5100 FT AND THE TCASII DSND WARNING HAD TERMINATED. WE CONTINUED THE CLB ON THE SID WITH NO FURTHER CONFLICT. THE CLOSEST POINT OF APCH APPEARED TO BE APPROX 2.5 MI LATERAL SEPARATION, 0 VERT. MY GUESS IS THAT TCASII GAVE US A DSND ADVISORY RATHER THAN CLB DUE TO THE 8500 FT TFC ABOVE.

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.