Narrative:

While flying a 210 degree magnetic heading en route to ewo VOR I observed one of these cloud/rain shafts about 5 mi ahead. It extended about 3 mi from east to west and 1 mi from north to south. The downdrafts producing the precipitation had pulled the base of the cloud down raggedly to about 6000-6500 ft MSL as evidenced by the fact that the cloud base was slightly obscuring the horizon from my present altitude. The rain shaft, which appeared to be a combination of virga and light rain, was light enough that I could see through the other side of it and 3 to 5 mi beyond. I began a descent so as to pass well beneath the base of the cloud and eventually ended up at 5500 ft MSL just as I entered the area of rain. The precipitation only lasted about 20-30 seconds before I flew out the southern side. About midway through the rain shaft I leaned over to the right slightly to better observe the engine gauges while I adjusted the power and mixture settings since I had just descended. As I completed this task and sat back upright in my seat I passed out of the rain shaft and immediately began a slow pitch up to initiate a climb back to the appropriate VFR direction of flight altitude of 6500 ft MSL. As I did this I observed an small transport twin engine at about my 2 O'clock position flying neasterly about 200-500 ft below and about 1800-2400 ft horizontally from me. He was in the process of initiating a slight left hand turn towards the north possibly in an effort to increase the separtation between us. By the time I observed the small transport and had idented him as a conflict he had already passed beneath me at my 3 O'clock position and was no longer a threat.

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Original NASA ASRS Text

Title: PLT OF AN SMT ATX ACFT DSNDED OFF THE CORRECT ALT FOR VFR HDG RULE RESULTING IN A NMAC WITH ANOTHER ACFT GOING THE OPPOSITE DIRECTION.

Narrative: WHILE FLYING A 210 DEG MAGNETIC HDG ENRTE TO EWO VOR I OBSERVED ONE OF THESE CLOUD/RAIN SHAFTS ABOUT 5 MI AHEAD. IT EXTENDED ABOUT 3 MI FROM E TO W AND 1 MI FROM N TO S. THE DOWNDRAFTS PRODUCING THE PRECIPITATION HAD PULLED THE BASE OF THE CLOUD DOWN RAGGEDLY TO ABOUT 6000-6500 FT MSL AS EVIDENCED BY THE FACT THAT THE CLOUD BASE WAS SLIGHTLY OBSCURING THE HORIZON FROM MY PRESENT ALT. THE RAIN SHAFT, WHICH APPEARED TO BE A COMBINATION OF VIRGA AND LIGHT RAIN, WAS LIGHT ENOUGH THAT I COULD SEE THROUGH THE OTHER SIDE OF IT AND 3 TO 5 MI BEYOND. I BEGAN A DSCNT SO AS TO PASS WELL BENEATH THE BASE OF THE CLOUD AND EVENTUALLY ENDED UP AT 5500 FT MSL JUST AS I ENTERED THE AREA OF RAIN. THE PRECIPITATION ONLY LASTED ABOUT 20-30 SECONDS BEFORE I FLEW OUT THE SOUTHERN SIDE. ABOUT MIDWAY THROUGH THE RAIN SHAFT I LEANED OVER TO THE R SLIGHTLY TO BETTER OBSERVE THE ENG GAUGES WHILE I ADJUSTED THE PWR AND MIXTURE SETTINGS SINCE I HAD JUST DSNDED. AS I COMPLETED THIS TASK AND SAT BACK UPRIGHT IN MY SEAT I PASSED OUT OF THE RAIN SHAFT AND IMMEDIATELY BEGAN A SLOW PITCH UP TO INITIATE A CLB BACK TO THE APPROPRIATE VFR DIRECTION OF FLT ALT OF 6500 FT MSL. AS I DID THIS I OBSERVED AN SMT TWIN ENG AT ABOUT MY 2 O'CLOCK POS FLYING NEASTERLY ABOUT 200-500 FT BELOW AND ABOUT 1800-2400 FT HORIZLY FROM ME. HE WAS IN THE PROCESS OF INITIATING A SLIGHT L HAND TURN TOWARDS THE N POSSIBLY IN AN EFFORT TO INCREASE THE SEPARTATION BTWN US. BY THE TIME I OBSERVED THE SMT AND HAD IDENTED HIM AS A CONFLICT HE HAD ALREADY PASSED BENEATH ME AT MY 3 O'CLOCK POS AND WAS NO LONGER A THREAT.

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.