Narrative:

While en route VFR from modesto to O70 in marginal VFR conditions which progressively deteriorated, small aircraft eventually went IMC in uncontrolled airspace and, in the process, flew lower than 500' AGL over uncongested airspace. As an instrument and similar to what I learned as a student pilot, I always said, 'if you go IMC while operating VFR, note your heading, maintain altitude and make a standard rate turn 180 degrees to where you came from' that rule works great at altitude, but at less than 1000' AGL in less than flat terrain, there is no telling what standard rate will allow you to run into. Small aircraft made a 180 degree turn at a bank angle of 30 degrees due to the fact that there were hills in the area and due to such reduced visibility there was no way of telling where those hills were exactly. A pilot should know his limitations, the airplane's limitations, and base a decision on those, the WX, and familiarity of the surrounding terrain. Stretching limits to 'get the job done' can cost as little as your pilot certificate and as much as your life, as well as other lives on the ground or passenger.

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Original NASA ASRS Text

Title: ATX SMA TRYING TO REACH DESTINATION, ENCOUNTERED CLOUDS, FLEW BELOW MINIMUM TERRAIN CLRNC ALT, AND BECAME VFR IN IMC.

Narrative: WHILE ENRTE VFR FROM MODESTO TO O70 IN MARGINAL VFR CONDITIONS WHICH PROGRESSIVELY DETERIORATED, SMA EVENTUALLY WENT IMC IN UNCONTROLLED AIRSPACE AND, IN THE PROCESS, FLEW LOWER THAN 500' AGL OVER UNCONGESTED AIRSPACE. AS AN INSTR AND SIMILAR TO WHAT I LEARNED AS A STUDENT PLT, I ALWAYS SAID, 'IF YOU GO IMC WHILE OPERATING VFR, NOTE YOUR HDG, MAINTAIN ALT AND MAKE A STANDARD RATE TURN 180 DEGS TO WHERE YOU CAME FROM' THAT RULE WORKS GREAT AT ALT, BUT AT LESS THAN 1000' AGL IN LESS THAN FLAT TERRAIN, THERE IS NO TELLING WHAT STANDARD RATE WILL ALLOW YOU TO RUN INTO. SMA MADE A 180 DEG TURN AT A BANK ANGLE OF 30 DEGS DUE TO THE FACT THAT THERE WERE HILLS IN THE AREA AND DUE TO SUCH REDUCED VISIBILITY THERE WAS NO WAY OF TELLING WHERE THOSE HILLS WERE EXACTLY. A PLT SHOULD KNOW HIS LIMITATIONS, THE AIRPLANE'S LIMITATIONS, AND BASE A DECISION ON THOSE, THE WX, AND FAMILIARITY OF THE SURROUNDING TERRAIN. STRETCHING LIMITS TO 'GET THE JOB DONE' CAN COST AS LITTLE AS YOUR PLT CERTIFICATE AND AS MUCH AS YOUR LIFE, AS WELL AS OTHER LIVES ON THE GND OR PAX.

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.