Narrative:

The ceiling was 900 ft with overcast at 1200 ft. As we entered the clouds, the plane was suddenly all over the sky with detroit departure trying to vector me and me being unable to fly the proper headings. My assigned altitude was 3000 ft and then I was cleared to 4000 ft but I was unable to fly it. The gyro, attitude indicator and compass were all swinging wildly with the vertical speed indicator going from 2000 FPM down to 2000 FPM up. Detroit departure then advised me to stay at 3000 ft. At that point I was able to follow the vectors and maintain altitude. It did not last very long and I was able to fly toward sarnia (zr) on the proper heading. I believe that the 2 jets taking off from ptk prior to my taking off were my problem in that I was in the wake turbulence of a cessna citation which took off immediately before me or the hawker siddley which had taken off just before the cessna. After much thought about the situation, I believe that if I had waited more time after the takeoff of the cessna, I would have been much better off. Fortunately my practice with unusual attitudes helped get the plane under control. Also, if the tower had reminded me about wake turbulence, I would have been more aware of it.

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Original NASA ASRS Text

Title: AC11 PLT LOST ACFT CTL AFTER ENTERING IMC. WAKE TURB FROM BIZJET TFC AHEAD MAY HAVE CONTRIBUTED.

Narrative: THE CEILING WAS 900 FT WITH OVCST AT 1200 FT. AS WE ENTERED THE CLOUDS, THE PLANE WAS SUDDENLY ALL OVER THE SKY WITH DETROIT DEP TRYING TO VECTOR ME AND ME BEING UNABLE TO FLY THE PROPER HDGS. MY ASSIGNED ALT WAS 3000 FT AND THEN I WAS CLRED TO 4000 FT BUT I WAS UNABLE TO FLY IT. THE GYRO, ATTITUDE INDICATOR AND COMPASS WERE ALL SWINGING WILDLY WITH THE VERT SPD INDICATOR GOING FROM 2000 FPM DOWN TO 2000 FPM UP. DETROIT DEP THEN ADVISED ME TO STAY AT 3000 FT. AT THAT POINT I WAS ABLE TO FOLLOW THE VECTORS AND MAINTAIN ALT. IT DID NOT LAST VERY LONG AND I WAS ABLE TO FLY TOWARD SARNIA (ZR) ON THE PROPER HDG. I BELIEVE THAT THE 2 JETS TAKING OFF FROM PTK PRIOR TO MY TAKING OFF WERE MY PROB IN THAT I WAS IN THE WAKE TURB OF A CESSNA CITATION WHICH TOOK OFF IMMEDIATELY BEFORE ME OR THE HAWKER SIDDLEY WHICH HAD TAKEN OFF JUST BEFORE THE CESSNA. AFTER MUCH THOUGHT ABOUT THE SIT, I BELIEVE THAT IF I HAD WAITED MORE TIME AFTER THE TKOF OF THE CESSNA, I WOULD HAVE BEEN MUCH BETTER OFF. FORTUNATELY MY PRACTICE WITH UNUSUAL ATTITUDES HELPED GET THE PLANE UNDER CTL. ALSO, IF THE TWR HAD REMINDED ME ABOUT WAKE TURB, I WOULD HAVE BEEN MORE AWARE OF IT.

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.