Lancair 200
Flight Crew Instrument; Flight Crew Private
Flight Crew Last 90 Days 35; Flight Crew Total 1575; Flight Crew Type 1375
Deviation - Altitude Excursion From Assigned Altitude; Deviation - Track / Heading All Types; Deviation / Discrepancy - Procedural Clearance; Inflight Event / Encounter Weather / Turbulence
Flight Crew Took Evasive Action
Aircraft; Weather
Was enroute at 9;000 FT. Light IMC conditions and suddenly experienced moderate to heavy turbulence and a strong updraft. Quickly called ATC and asked for a deviation to exit what was apparently a build-up. The flight had been smooth up until that point. I have satellite weather; but no NEXRAD images were returned for the area I was in (nothing within about 50 miles). I was expecting build-ups and the need to dodge some cumulus activity; but not for another 50 or more miles. I should have been clearer with the Controller that I was deviating and not waiting for a deviation approval; we were getting beaten up quite severely. I turned off lateral course control on the autopilot and the altitude hold because the autopilot was causing significant and abrupt pitch changes. I deviated west of course and my altitude also varied (increasing to about 9;300). After exiting the situation the Controller called and asked for the purpose of the deviation (he had noticed the change while he was asking Savannah for the deviation) and I reported turbulence from a buildup and apologized for the deviation. My primary goal was to exit the moderate to heavy turbulence and minimize pitch changes.
Lancair pilot reports encountering heavy turbulence with up drafts at 9;000 FT causing an altitude deviation. A course deviation is requested from ATC then commenced before a clearance is received. NEXRAD weather did not display any buildups within 50 NM.