Narrative:

I departed winchester, va on an IFR flight plan to taylor county, ky. On climb out I proceeded through a broken cloud layer from approximately 4000 to 5500 ft. I was cleared to 8000 ft and experienced no turbulence, but light rime ice in the clouds, but left the aircraft as soon as I broke out into the sunlight. Winds were briefed by mrb FSS to be out of the west at about 45. Everything was smooth until about 40 west of linden VOR. I could see a cloud bank ahead, but it did not appear to be anything. I called washington center and asked for 10000 and was cleared to 10000. I started to climb just as I reach this first cloud bank. As I was climbing I started to experience a down draft, but was able to continue to climb even though the airspeed dropped off to about 110 IAS, as I went through 9000, I entered the updraft and leveled at 10000, maintain 10000 ft, IAS continued to build to over 200 IAS for about 30 seconds and ten everything returned to normal. Cruising at 10000 ft with 160 KIAS. At about 50 NM west of linden about 40 east of elkins, I observed another cloud bank at my altitude, I called washing center and ask for 12000 ft to get above this cloud bank. As I passed through these cloud tops I would get a trace for rime ice and did not want to stay in the clouds for a prolonged period of time. As center finally cleared me to 12000 ft I was getting over close to this cloud bank. I started the climb but at the time must have hit the second downdraft. My IAS started dropping and to maintain 10000 I was below 100 IAS, my IAS started dropping further and the stall warning sounded. At this time the aircraft started descending. I applied maximum power, maximum RPM and trying to maintain level flight with IAS above the stall, I maintained control my altitude was down to about 9300 ft, center call and asked about altitude, I advised him of my difficulty and requested 8000 ft. I felt that I could maintain 8000. I continued my descent to 8000 and after a min or so, broke out in the clear. I continued my flight on to taylor co. With no further incident. Washington center called me and I explained what had happened to me. I have never encountered that severe of a mountain wave or downdraft in that area in my flying experience. That the fact could not fly out of. I feel that the WX briefing I received was excellent, and this incident would be very hard to predict.

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Original NASA ASRS Text

Title: SMT EXPERIENCES EXTREME DOWNDRAFT, UNABLE HOLD ALT. ALSO HAS SOME ICING DURING FLT.

Narrative: I DEPARTED WINCHESTER, VA ON AN IFR FLT PLAN TO TAYLOR COUNTY, KY. ON CLB OUT I PROCEEDED THROUGH A BROKEN CLOUD LAYER FROM APPROX 4000 TO 5500 FT. I WAS CLRED TO 8000 FT AND EXPERIENCED NO TURB, BUT LIGHT RIME ICE IN THE CLOUDS, BUT L THE ACFT AS SOON AS I BROKE OUT INTO THE SUNLIGHT. WINDS WERE BRIEFED BY MRB FSS TO BE OUT OF THE W AT ABOUT 45. EVERYTHING WAS SMOOTH UNTIL ABOUT 40 W OF LINDEN VOR. I COULD SEE A CLOUD BANK AHEAD, BUT IT DID NOT APPEAR TO BE ANYTHING. I CALLED WASHINGTON CTR AND ASKED FOR 10000 AND WAS CLRED TO 10000. I STARTED TO CLB JUST AS I REACH THIS FIRST CLOUD BANK. AS I WAS CLBING I STARTED TO EXPERIENCE A DOWN DRAFT, BUT WAS ABLE TO CONTINUE TO CLB EVEN THOUGH THE AIRSPD DROPPED OFF TO ABOUT 110 IAS, AS I WENT THROUGH 9000, I ENTERED THE UPDRAFT AND LEVELED AT 10000, MAINTAIN 10000 FT, IAS CONTINUED TO BUILD TO OVER 200 IAS FOR ABOUT 30 SECONDS AND TEN EVERYTHING RETURNED TO NORMAL. CRUISING AT 10000 FT WITH 160 KIAS. AT ABOUT 50 NM W OF LINDEN ABOUT 40 E OF ELKINS, I OBSERVED ANOTHER CLOUD BANK AT MY ALT, I CALLED WASHING CTR AND ASK FOR 12000 FT TO GET ABOVE THIS CLOUD BANK. AS I PASSED THROUGH THESE CLOUD TOPS I WOULD GET A TRACE FOR RIME ICE AND DID NOT WANT TO STAY IN THE CLOUDS FOR A PROLONGED PERIOD OF TIME. AS CTR FINALLY CLRED ME TO 12000 FT I WAS GETTING OVER CLOSE TO THIS CLOUD BANK. I STARTED THE CLB BUT AT THE TIME MUST HAVE HIT THE SECOND DOWNDRAFT. MY IAS STARTED DROPPING AND TO MAINTAIN 10000 I WAS BELOW 100 IAS, MY IAS STARTED DROPPING FURTHER AND THE STALL WARNING SOUNDED. AT THIS TIME THE ACFT STARTED DSNDING. I APPLIED MAX PWR, MAX RPM AND TRYING TO MAINTAIN LEVEL FLT WITH IAS ABOVE THE STALL, I MAINTAINED CTL MY ALT WAS DOWN TO ABOUT 9300 FT, CTR CALL AND ASKED ABOUT ALT, I ADVISED HIM OF MY DIFFICULTY AND REQUESTED 8000 FT. I FELT THAT I COULD MAINTAIN 8000. I CONTINUED MY DSCNT TO 8000 AND AFTER A MIN OR SO, BROKE OUT IN THE CLR. I CONTINUED MY FLT ON TO TAYLOR CO. WITH NO FURTHER INCIDENT. WASHINGTON CTR CALLED ME AND I EXPLAINED WHAT HAD HAPPENED TO ME. I HAVE NEVER ENCOUNTERED THAT SEVERE OF A MOUNTAIN WAVE OR DOWNDRAFT IN THAT AREA IN MY FLYING EXPERIENCE. THAT THE FACT COULD NOT FLY OUT OF. I FEEL THAT THE WX BRIEFING I RECEIVED WAS EXCELLENT, AND THIS INCIDENT WOULD BE VERY HARD TO PREDICT.

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.