Narrative:

While on IFR flight through overcast and broken cloud decks, I encountered unrpted (by way of PIREPS and radar) severe up and downdrafts, with moderate to heavy rime ice. Attempted to request a reverse direction clearance and 180 degree turn on 2 occasions. Radio congestion made request difficult and unsuccessful. Subsequently executed a 180 degree turn to exit what appeared to be an embedded cell. Contacted ATC when out of severe turbulence and notified them of situation. No known conflict occurred, received new clearance and landed at daggett airport.

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Original NASA ASRS Text

Title: UNAUTHORIZED UNCOORDINATED HDG TRACK CHANGE IN IMC CONDITIONS. DEV NON ADHERENCE TO ATC CLRNC.

Narrative: WHILE ON IFR FLT THROUGH OVCST AND BROKEN CLOUD DECKS, I ENCOUNTERED UNRPTED (BY WAY OF PIREPS AND RADAR) SEVERE UP AND DOWNDRAFTS, WITH MODERATE TO HVY RIME ICE. ATTEMPTED TO REQUEST A REVERSE DIRECTION CLRNC AND 180 DEG TURN ON 2 OCCASIONS. RADIO CONGESTION MADE REQUEST DIFFICULT AND UNSUCCESSFUL. SUBSEQUENTLY EXECUTED A 180 DEG TURN TO EXIT WHAT APPEARED TO BE AN EMBEDDED CELL. CONTACTED ATC WHEN OUT OF SEVERE TURB AND NOTIFIED THEM OF SITUATION. NO KNOWN CONFLICT OCCURRED, RECEIVED NEW CLRNC AND LANDED AT DAGGETT ARPT.

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.