Narrative:

I had been providing insurance required recurrent flight training in a C337 skymaster. We had just completed the RNAV (GPS) runway 10 to O27 and were making the published missed approach to the holding pattern at wraps intersection. Prior to the procedure turn outbound; the controller asked us to advise procedure turn inbound. While inbound; the controller advised cleared approach make published missed approach VFR to wraps. We acknowledged and went to advisory frequency. On missed we called and advised of our making the missed approach and our proceeding to wraps. I noted a different controller at that time. A moment later; the next transmission we hear from norcal is 'traffic alert' an alarus aircraft 12 O'clock position; traffic holding over wraps at 3000 ft MSL. I stopped the climb by guarding the yoke with a slight turn left to avoid the alarus. There was no mention of another aircraft holding over wraps prior to switching to oakdale advisory nor was there mention from the second controller upon our first call-up on the missed approach. I advised norcal of an near midair collision. There was no response from norcal. He asked a few mins later as to our intentions. The next transmission was from us advising of our intentions to proceed to eca VOR for another approach. There was no further conflict that day.

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Original NASA ASRS Text

Title: A C337 EXPERIENCED AN NMAC DURING TRAINING IN THE VICINITY OF O27.

Narrative: I HAD BEEN PROVIDING INSURANCE REQUIRED RECURRENT FLT TRAINING IN A C337 SKYMASTER. WE HAD JUST COMPLETED THE RNAV (GPS) RWY 10 TO O27 AND WERE MAKING THE PUBLISHED MISSED APCH TO THE HOLDING PATTERN AT WRAPS INTXN. PRIOR TO THE PROC TURN OUTBOUND; THE CTLR ASKED US TO ADVISE PROC TURN INBOUND. WHILE INBOUND; THE CTLR ADVISED CLRED APCH MAKE PUBLISHED MISSED APCH VFR TO WRAPS. WE ACKNOWLEDGED AND WENT TO ADVISORY FREQ. ON MISSED WE CALLED AND ADVISED OF OUR MAKING THE MISSED APCH AND OUR PROCEEDING TO WRAPS. I NOTED A DIFFERENT CTLR AT THAT TIME. A MOMENT LATER; THE NEXT XMISSION WE HEAR FROM NORCAL IS 'TFC ALERT' AN ALARUS ACFT 12 O'CLOCK POS; TFC HOLDING OVER WRAPS AT 3000 FT MSL. I STOPPED THE CLB BY GUARDING THE YOKE WITH A SLIGHT TURN L TO AVOID THE ALARUS. THERE WAS NO MENTION OF ANOTHER ACFT HOLDING OVER WRAPS PRIOR TO SWITCHING TO OAKDALE ADVISORY NOR WAS THERE MENTION FROM THE SECOND CTLR UPON OUR FIRST CALL-UP ON THE MISSED APCH. I ADVISED NORCAL OF AN NMAC. THERE WAS NO RESPONSE FROM NORCAL. HE ASKED A FEW MINS LATER AS TO OUR INTENTIONS. THE NEXT XMISSION WAS FROM US ADVISING OF OUR INTENTIONS TO PROCEED TO ECA VOR FOR ANOTHER APCH. THERE WAS NO FURTHER CONFLICT THAT DAY.

Data retrieved from NASA's ASRS site as of January 2009 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.