Narrative:

I was en route from north western pennsylvania to a small airport in west virginia. WX showed that there was some IFR WX due to overcast layer in between my departure and destination airports. WX reports showed; that the WX would be improving rapidly and that my current airport was better than VFR WX minimums. I elected to takeoff and get above the cloud layer; since my departure airport was VFR with no ceiling. Cruising at 4500 ft; I was above a broken to overcast layer; however I had VFR WX and clouds in view during the flight in the distance off of my right or left at all times. I contacted pittsburg class B approach to transition their airspace. After about 30 mins into the class B airspace; the visibility at my altitude started to drop and the clouds became a thick overcast below me. I could no longer see VFR WX and clouds anywhere in the distance. I elected to continue knowing that good WX should be ahead from what the WX reports and trends were showing. I was about 1 hour into my 2 hours of fuel onboard and started to get nervous about the possibility of getting stuck on top of the clouds in an airplane without any gyro instruments. I called approach and asked how the WX was at pittsburg int'l. It was VFR with scattered clouds at 2700 ft. I felt a bit relived knowing that there was airports in the vicinity with VFR WX. I continued and once clear of the class B airspace; I terminated radar services. With about 45 min of fuel on board left; I decided that the next break in clouds that I saw; I would get below the clouds and cruise to my destination below them instead of being above them. I found a good sized hole to allow me to descend VFR down. I kept descending and the clouds seemed to be getting lower and lower with the visibilities dropping. I was finally able to get below the clouds probably around 300 to 500 ft above the ground. The visibility was approximately 2 to 3 mi. The clouds and visibility varied greatly as I continued on my on course heading. I saw ahead to what looked like a wall of extremely low ground scud/fog with visibility near zero. I turned around immediately and headed to the closet airport. The airport was about 10 mi away. I had to fly anywhere from 200 to 400 ft AGL to be out of the clouds. The visibility would go in and out from approximately 1 mi to 2 mi. I could see little breaks in the clouds; but I would be unable to climb at a rate fast enough to get above them without penetrating them. I made it to the airport and the WX gradually turned to VFR with scattered clouds around 1500 ft AGL and about 5 mi visibility. Being shook-up from the WX and situation I had just encountered the landing was a hair rough; but uneventful. I believe that my first mistake was to elect to go from the beginning. My second mistake was to get down below the clouds without knowing the WX that was underneath me. I should have called flight service and gotten various WX reports for airports nearby. If I was above the clouds; I could have easily flown to the airport that I diverted to above the layer and then descended once the clouds broke near the airport.

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Original NASA ASRS Text

Title: A CHRISTEN EAGLE II PLT; ATTEMPTING TO REMAIN VFR; DESCENDED VERY LOW; ENCOUNTERED IMC; REVERSED COURSE; AND LANDED.

Narrative: I WAS ENRTE FROM NORTH WESTERN PENNSYLVANIA TO A SMALL ARPT IN WEST VIRGINIA. WX SHOWED THAT THERE WAS SOME IFR WX DUE TO OVERCAST LAYER IN BETWEEN MY DEP AND DEST ARPTS. WX RPTS SHOWED; THAT THE WX WOULD BE IMPROVING RAPIDLY AND THAT MY CURRENT ARPT WAS BETTER THAN VFR WX MINIMUMS. I ELECTED TO TKOF AND GET ABOVE THE CLOUD LAYER; SINCE MY DEP ARPT WAS VFR WITH NO CEILING. CRUISING AT 4500 FT; I WAS ABOVE A BROKEN TO OVERCAST LAYER; HOWEVER I HAD VFR WX AND CLOUDS IN VIEW DURING THE FLT IN THE DISTANCE OFF OF MY R OR L AT ALL TIMES. I CONTACTED PITTSBURG CLASS B APCH TO TRANSITION THEIR AIRSPACE. AFTER ABOUT 30 MINS INTO THE CLASS B AIRSPACE; THE VISIBILITY AT MY ALT STARTED TO DROP AND THE CLOUDS BECAME A THICK OVERCAST BELOW ME. I COULD NO LONGER SEE VFR WX AND CLOUDS ANYWHERE IN THE DISTANCE. I ELECTED TO CONTINUE KNOWING THAT GOOD WX SHOULD BE AHEAD FROM WHAT THE WX RPTS AND TRENDS WERE SHOWING. I WAS ABOUT 1 HOUR INTO MY 2 HOURS OF FUEL ONBOARD AND STARTED TO GET NERVOUS ABOUT THE POSSIBILITY OF GETTING STUCK ON TOP OF THE CLOUDS IN AN AIRPLANE WITHOUT ANY GYRO INSTRUMENTS. I CALLED APCH AND ASKED HOW THE WX WAS AT PITTSBURG INT'L. IT WAS VFR WITH SCATTERED CLOUDS AT 2700 FT. I FELT A BIT RELIVED KNOWING THAT THERE WAS ARPTS IN THE VICINITY WITH VFR WX. I CONTINUED AND ONCE CLR OF THE CLASS B AIRSPACE; I TERMINATED RADAR SVCS. WITH ABOUT 45 MIN OF FUEL ON BOARD LEFT; I DECIDED THAT THE NEXT BREAK IN CLOUDS THAT I SAW; I WOULD GET BELOW THE CLOUDS AND CRUISE TO MY DEST BELOW THEM INSTEAD OF BEING ABOVE THEM. I FOUND A GOOD SIZED HOLE TO ALLOW ME TO DSND VFR DOWN. I KEPT DESCENDING AND THE CLOUDS SEEMED TO BE GETTING LOWER AND LOWER WITH THE VISIBILITIES DROPPING. I WAS FINALLY ABLE TO GET BELOW THE CLOUDS PROBABLY AROUND 300 TO 500 FT ABOVE THE GND. THE VISIBILITY WAS APPROX 2 TO 3 MI. THE CLOUDS AND VISIBILITY VARIED GREATLY AS I CONTINUED ON MY ON COURSE HEADING. I SAW AHEAD TO WHAT LOOKED LIKE A WALL OF EXTREMELY LOW GROUND SCUD/FOG WITH VISIBILITY NEAR ZERO. I TURNED AROUND IMMEDIATELY AND HEADED TO THE CLOSET ARPT. THE ARPT WAS ABOUT 10 MI AWAY. I HAD TO FLY ANYWHERE FROM 200 TO 400 FT AGL TO BE OUT OF THE CLOUDS. THE VISIBILITY WOULD GO IN AND OUT FROM APPROX 1 MI TO 2 MI. I COULD SEE LITTLE BREAKS IN THE CLOUDS; BUT I WOULD BE UNABLE TO CLB AT A RATE FAST ENOUGH TO GET ABOVE THEM WITHOUT PENETRATING THEM. I MADE IT TO THE ARPT AND THE WX GRADUALLY TURNED TO VFR WITH SCATTERED CLOUDS AROUND 1500 FT AGL AND ABOUT 5 MI VISIBILITY. BEING SHOOK-UP FROM THE WX AND SIT I HAD JUST ENCOUNTERED THE LANDING WAS A HAIR ROUGH; BUT UNEVENTFUL. I BELIEVE THAT MY FIRST MISTAKE WAS TO ELECT TO GO FROM THE BEGINNING. MY SECOND MISTAKE WAS TO GET DOWN BELOW THE CLOUDS WITHOUT KNOWING THE WX THAT WAS UNDERNEATH ME. I SHOULD HAVE CALLED FLT SVC AND GOTTEN VARIOUS WX RPTS FOR ARPTS NEARBY. IF I WAS ABOVE THE CLOUDS; I COULD HAVE EASILY FLOWN TO THE ARPT THAT I DIVERTED TO ABOVE THE LAYER AND THEN DESCENDED ONCE THE CLOUDS BROKE NEAR THE ARPT.

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.