Narrative:

As we were climbing out of psp on an assigned heading of 300' to intercept V388 with a climb to 12000' MSL, the copilot called traffic at 11 O'clock. I spotted the traffic as he initiated a turn to the right. I then increased the rate of climb and the bank angle to avoid the aircraft. As he passed to the left and below we observed him making a right turn also. The traffic had not been reported. The seatbelt and no smoking signs were still on and everyone was seated. The evasive action was only moderate and no one was hurt. After reaching ont, I called the psp supervisor and reported the near midair collision. He had talked to the other pilot who works for a commuter air carrier. Supplemental information from acn 93194: eastbound through banning pass, tuning in psp approach, level at 7500', I saw a plane climbing in my blind spot through altitude. I called the controller and he idented me squawking 1200 at 7500', 4 mi east of psp VOR. I asked him if he called us out to the air carrier medium large transport. He said he did not see us on radar west of the VOR. I feel that the controller just did not call us as traffic, possibly a student controller. All other psp controllers did see us. I talked to the medium large transport captain and he said psp radar said we had no transponder on. We had it on mode C, 1200 all the time.

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Original NASA ASRS Text

Title: CLOSE PROX ACR-MLG COMMUTER-SMT 4 NM WEST OF PSP.

Narrative: AS WE WERE CLBING OUT OF PSP ON AN ASSIGNED HDG OF 300' TO INTERCEPT V388 WITH A CLB TO 12000' MSL, THE COPLT CALLED TFC AT 11 O'CLOCK. I SPOTTED THE TFC AS HE INITIATED A TURN TO THE RIGHT. I THEN INCREASED THE RATE OF CLB AND THE BANK ANGLE TO AVOID THE ACFT. AS HE PASSED TO THE LEFT AND BELOW WE OBSERVED HIM MAKING A RIGHT TURN ALSO. THE TFC HAD NOT BEEN RPTED. THE SEATBELT AND NO SMOKING SIGNS WERE STILL ON AND EVERYONE WAS SEATED. THE EVASIVE ACTION WAS ONLY MODERATE AND NO ONE WAS HURT. AFTER REACHING ONT, I CALLED THE PSP SUPVR AND RPTED THE NMAC. HE HAD TALKED TO THE OTHER PLT WHO WORKS FOR A COMMUTER ACR. SUPPLEMENTAL INFO FROM ACN 93194: EBND THROUGH BANNING PASS, TUNING IN PSP APCH, LEVEL AT 7500', I SAW A PLANE CLBING IN MY BLIND SPOT THROUGH ALT. I CALLED THE CTLR AND HE IDENTED ME SQUAWKING 1200 AT 7500', 4 MI E OF PSP VOR. I ASKED HIM IF HE CALLED US OUT TO THE ACR MLG. HE SAID HE DID NOT SEE US ON RADAR W OF THE VOR. I FEEL THAT THE CTLR JUST DID NOT CALL US AS TFC, POSSIBLY A STUDENT CTLR. ALL OTHER PSP CTLRS DID SEE US. I TALKED TO THE MLG CAPT AND HE SAID PSP RADAR SAID WE HAD NO TRANSPONDER ON. WE HAD IT ON MODE C, 1200 ALL THE TIME.

Data retrieved from NASA's ASRS site as of August 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.