Narrative:

I was the instrument instructor on the last leg of an IFR cross country flight. WX conditions at the time were VMC with a thunderstorm building to the west of my destination airport. My student and I had requested the full NDB approach to runway 11R. As we were flying west, outbound on the approach course, I noticed that the thunderstorm was moving eastward in our direction. At this time my student had initiated his procedure turn in the wrong direction so we asked to be revectored around for another approach. At this time we were getting too close to thunderstorm, so I requested a vector to rejoin our final approach course. He gave us a vector of 270 degrees to extend our downwind leg which was bringing us closer to the thunderstorm. I then requested a vector to the north to reintercept final and he gave me a right turn to 070 degrees. As we initiated our right turn, we flew into the outer edge of the thunderstorm. Immediately upon entering the thunderstorm at 3000 ft, I noticed we were caught in an updraft. I took the controls, reduced power, and shoved the nose down. I immediately contacted ZMA and told him we were caught in an updraft. And were unable to maintain altitude. He immediately vectored traffic away from my position. (Aircraft holding 7 NM away over the NDB.) I continued my right turn to 070 degrees and tried, with little success, to descend. The updraft had caused an altitude gain of 1000 ft. When I flew out of the thunderstorm, I advised center I was able to maintain altitude. At this time I canceled IFR and flew back VFR. Had I'd been more persistent with center in requesting vectors to avoid the cell, flight into the cell may have been avoided.

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Original NASA ASRS Text

Title: INSTRUCTOR PLT CLBED ABOVE ASSIGNED ALT DURING AN IFR APCH DUE TO A SEVERE UPDRAFT CAUSED BY A TSTM.

Narrative: I WAS THE INST INSTRUCTOR ON THE LAST LEG OF AN IFR XCOUNTRY FLT. WX CONDITIONS AT THE TIME WERE VMC WITH A TSTM BUILDING TO THE W OF MY DEST ARPT. MY STUDENT AND I HAD REQUESTED THE FULL NDB APCH TO RWY 11R. AS WE WERE FLYING W, OUTBOUND ON THE APCH COURSE, I NOTICED THAT THE TSTM WAS MOVING EASTWARD IN OUR DIRECTION. AT THIS TIME MY STUDENT HAD INITIATED HIS PROC TURN IN THE WRONG DIRECTION SO WE ASKED TO BE REVECTORED AROUND FOR ANOTHER APCH. AT THIS TIME WE WERE GETTING TOO CLOSE TO TSTM, SO I REQUESTED A VECTOR TO REJOIN OUR FINAL APCH COURSE. HE GAVE US A VECTOR OF 270 DEGS TO EXTEND OUR DOWNWIND LEG WHICH WAS BRINGING US CLOSER TO THE TSTM. I THEN REQUESTED A VECTOR TO THE N TO REINTERCEPT FINAL AND HE GAVE ME A R TURN TO 070 DEGS. AS WE INITIATED OUR R TURN, WE FLEW INTO THE OUTER EDGE OF THE TSTM. IMMEDIATELY UPON ENTERING THE TSTM AT 3000 FT, I NOTICED WE WERE CAUGHT IN AN UPDRAFT. I TOOK THE CTLS, REDUCED PWR, AND SHOVED THE NOSE DOWN. I IMMEDIATELY CONTACTED ZMA AND TOLD HIM WE WERE CAUGHT IN AN UPDRAFT. AND WERE UNABLE TO MAINTAIN ALT. HE IMMEDIATELY VECTORED TFC AWAY FROM MY POS. (ACFT HOLDING 7 NM AWAY OVER THE NDB.) I CONTINUED MY R TURN TO 070 DEGS AND TRIED, WITH LITTLE SUCCESS, TO DSND. THE UPDRAFT HAD CAUSED AN ALT GAIN OF 1000 FT. WHEN I FLEW OUT OF THE TSTM, I ADVISED CTR I WAS ABLE TO MAINTAIN ALT. AT THIS TIME I CANCELED IFR AND FLEW BACK VFR. HAD I'D BEEN MORE PERSISTENT WITH CTR IN REQUESTING VECTORS TO AVOID THE CELL, FLT INTO THE CELL MAY HAVE BEEN AVOIDED.

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.