Narrative:

I was conducting a training flight to evaluate a perspective pilot employee and, even though it was a cavu day, elected to do it IFR to ensure protection from other traffic arriving and departing from cle, pit and cak. Traffic was heavy and center assigned us an area to work in and almost immediately put us on vectors. To get some value from the time we were spending in an unproductive manner. I took control of the aircraft to demonstrate landing confign 'slow flight' and approach to a stall (this I erroneously felt I could do at the assigned 14000'). Just as the stick shaker activated, we encountered turbulence, which put us in an immediate stall. A wind dropped abruptly. I decreased the angle of attach added takeoff thrust, leveled the wings. I then realized that we were in danger of going out of our assigned altitude, increased the angle of attack too abruptly and entered an accelerated stall which was violent from the latitude perspective. I had to take very positive action to recover from the one. The pilot being evaluated said that he observed us 400' below assigned altitude. ZOB called at about that time to advise of the altitude deviation and request return to assigned altitude. My lesson from this is that one should never, ever do anything that could result in altitude loss or other deviations west/O having proper buffers of altitude and latitude space. If the unexpected can happen, it will happen. I recognize that I was overconfident of my abilities to deal with the situation. I never expected turbulence of that magnitude and even if the turbulence weren't there I used poor judgement. The aircraft we were flying was certified using the 'loss of pitch control' to determine the point of stall. The far's allowed the stall warning to activate at the same $ of stall as in the past. What has resulted is the stall warning (stick shaker) is, from a practical point of view, an enunicator of the wrong stall. This is a terrible situation which may have resulted in a fatal accident several yrs ago. Also, this aircraft is known to have nasty stall characteristics in the dirty confign--it really drops a wind abruptly and virtually uncontrollably. This aircraft needs a 'stick pusher.'

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Original NASA ASRS Text

Title: ALT DEVIATION ON TRAINING FLT.

Narrative: I WAS CONDUCTING A TRNING FLT TO EVALUATE A PERSPECTIVE PLT EMPLOYEE AND, EVEN THOUGH IT WAS A CAVU DAY, ELECTED TO DO IT IFR TO ENSURE PROTECTION FROM OTHER TFC ARRIVING AND DEPARTING FROM CLE, PIT AND CAK. TFC WAS HEAVY AND CENTER ASSIGNED US AN AREA TO WORK IN AND ALMOST IMMEDIATELY PUT US ON VECTORS. TO GET SOME VALUE FROM THE TIME WE WERE SPENDING IN AN UNPRODUCTIVE MANNER. I TOOK CTL OF THE ACFT TO DEMONSTRATE LNDG CONFIGN 'SLOW FLT' AND APCH TO A STALL (THIS I ERRONEOUSLY FELT I COULD DO AT THE ASSIGNED 14000'). JUST AS THE STICK SHAKER ACTIVATED, WE ENCOUNTERED TURB, WHICH PUT US IN AN IMMEDIATE STALL. A WIND DROPPED ABRUPTLY. I DECREASED THE ANGLE OF ATTACH ADDED TKOF THRUST, LEVELED THE WINGS. I THEN REALIZED THAT WE WERE IN DANGER OF GOING OUT OF OUR ASSIGNED ALT, INCREASED THE ANGLE OF ATTACK TOO ABRUPTLY AND ENTERED AN ACCELERATED STALL WHICH WAS VIOLENT FROM THE LAT PERSPECTIVE. I HAD TO TAKE VERY POSITIVE ACTION TO RECOVER FROM THE ONE. THE PLT BEING EVALUATED SAID THAT HE OBSERVED US 400' BELOW ASSIGNED ALT. ZOB CALLED AT ABOUT THAT TIME TO ADVISE OF THE ALT DEVIATION AND REQUEST RETURN TO ASSIGNED ALT. MY LESSON FROM THIS IS THAT ONE SHOULD NEVER, EVER DO ANYTHING THAT COULD RESULT IN ALT LOSS OR OTHER DEVIATIONS W/O HAVING PROPER BUFFERS OF ALT AND LAT SPACE. IF THE UNEXPECTED CAN HAPPEN, IT WILL HAPPEN. I RECOGNIZE THAT I WAS OVERCONFIDENT OF MY ABILITIES TO DEAL WITH THE SITUATION. I NEVER EXPECTED TURB OF THAT MAGNITUDE AND EVEN IF THE TURB WEREN'T THERE I USED POOR JUDGEMENT. THE ACFT WE WERE FLYING WAS CERTIFIED USING THE 'LOSS OF PITCH CTL' TO DETERMINE THE POINT OF STALL. THE FAR'S ALLOWED THE STALL WARNING TO ACTIVATE AT THE SAME $ OF STALL AS IN THE PAST. WHAT HAS RESULTED IS THE STALL WARNING (STICK SHAKER) IS, FROM A PRACTICAL POINT OF VIEW, AN ENUNICATOR OF THE WRONG STALL. THIS IS A TERRIBLE SITUATION WHICH MAY HAVE RESULTED IN A FATAL ACCIDENT SEVERAL YRS AGO. ALSO, THIS ACFT IS KNOWN TO HAVE NASTY STALL CHARACTERISTICS IN THE DIRTY CONFIGN--IT REALLY DROPS A WIND ABRUPTLY AND VIRTUALLY UNCONTROLLABLY. THIS ACFT NEEDS A 'STICK PUSHER.'

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.