Narrative:

I was en route for paine field, wa to redding, ca, approaching medford. ZSE had asked me to climb from my cruising altitude of 9000' about 1/2 hour prior. I requested and got VFR on top with continued flight monitoring, after which I climbed to 9500' (this was to avoid going higher west/O O2). About 15 mins later, a deck of clouds ahead forced me to descend to maintain VFR. I informed ZSE, got a reply, 'maintain VFR,' and started a slow descent. Shortly afterward, a buildup in my flight path on the arwy forced a deviation left. I told ZSE I was deviating left and continued a slow descent. Again I received, 'maintain VFR.' about 3 mins later with the buildup off my right wing, maintaining VFR clear of clouds I received a hurried call from center to the effect that there was an aircraft, 'departing medford 040 radial.' about 45 seconds later, I observed a twin turbulence pass in front, about 500' low and 2000' in front. I reported the aircraft to ZSE. About 10 mins later the controller queried me on how close it had been and I told him. The call from ZSE was, in my opinion, not sufficiently informative to warn of an impending near miss. Verbiage such as, 'aircraft in your 2 O'clock position, indicating (altitude),' would have been better. It sounded like the controller was a little late spotting the situation.

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Original NASA ASRS Text

Title: POTENTIAL CONFLICT OCCURS AS SMA DRIFTS DOWN IN CTLED AIRSPACE IN VFR FLT.

Narrative: I WAS ENRTE FOR PAINE FIELD, WA TO REDDING, CA, APCHING MEDFORD. ZSE HAD ASKED ME TO CLB FROM MY CRUISING ALT OF 9000' ABOUT 1/2 HR PRIOR. I REQUESTED AND GOT VFR ON TOP WITH CONTINUED FLT MONITORING, AFTER WHICH I CLBED TO 9500' (THIS WAS TO AVOID GOING HIGHER W/O O2). ABOUT 15 MINS LATER, A DECK OF CLOUDS AHEAD FORCED ME TO DSND TO MAINTAIN VFR. I INFORMED ZSE, GOT A REPLY, 'MAINTAIN VFR,' AND STARTED A SLOW DSNT. SHORTLY AFTERWARD, A BUILDUP IN MY FLT PATH ON THE ARWY FORCED A DEVIATION LEFT. I TOLD ZSE I WAS DEVIATING LEFT AND CONTINUED A SLOW DSNT. AGAIN I RECEIVED, 'MAINTAIN VFR.' ABOUT 3 MINS LATER WITH THE BUILDUP OFF MY RIGHT WING, MAINTAINING VFR CLR OF CLOUDS I RECEIVED A HURRIED CALL FROM CENTER TO THE EFFECT THAT THERE WAS AN ACFT, 'DEPARTING MEDFORD 040 RADIAL.' ABOUT 45 SECS LATER, I OBSERVED A TWIN TURB PASS IN FRONT, ABOUT 500' LOW AND 2000' IN FRONT. I RPTED THE ACFT TO ZSE. ABOUT 10 MINS LATER THE CTLR QUERIED ME ON HOW CLOSE IT HAD BEEN AND I TOLD HIM. THE CALL FROM ZSE WAS, IN MY OPINION, NOT SUFFICIENTLY INFORMATIVE TO WARN OF AN IMPENDING NEAR MISS. VERBIAGE SUCH AS, 'ACFT IN YOUR 2 O'CLOCK POS, INDICATING (ALT),' WOULD HAVE BEEN BETTER. IT SOUNDED LIKE THE CTLR WAS A LITTLE LATE SPOTTING THE SITUATION.

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.