Narrative:

I am a CFI. A student of mine and I were flying at 800 ft AGL when I pulled the throttle back to idle to simulate an engine failure. I asked the student what he would do. The student had between 10-15 hours total time -- no solo. He and I had done an engine out twice before. The student began a simulated emergency approach to a field. I pointed out a frozen lake to him, which is a better choice in winter months in minnesota because it is well known that even 2 or 3 inches of ice can support tons of weight and it is a long, flat surface. We continued the emergency approach below 500 ft but still stayed thousands of ft away from any persons or properties (rural area). I took the plane's controls momentarily (after verbal) and showed the student a slip in order to make his landing point. We descended to probably 100-200 ft AGL and I told the student to add full power and execute a climb back to 800 ft AGL. After he added full throttle, about 10 seconds later the engine sounded like it went back to idle. When I looked at the student's hand on the throttle I saw the throttle was applied to full, and that is when I realized we had an engine failure. In my emergency procedures actions I immediately discovered the fuel shut-off valve was in the off position. I turned the fuel shut-off valve back on and attempted a restart with no success. At about 20 ft above the lake (which we were still over) I shut the valve off, mixture off, key off, and master switch off and executed a forced landing on the lake. No damage was done to the plane nor did the student and I suffer even the slightest injury. The cause of the incident is obvious. During the descent, the student shut the fuel valve off. When I asked him why he had shut it off he said he was thinking that in an actual emergency you would shut the fuel valve off and for some reason he actually did it -- a mental error. Why did I not see him do it? In a C150 the fuel shut off valve is between the 2 occupant's seats on a vertical ledge. The only way to check it is by feeling it. There is absolutely no way to visually check the valve while sitting in the airplane. There was also no reason for me to think just because his hand went down to the fuel valve that he would shut it off for a variety of reasons. First, I have always been taught to go through motions of checking the system and I teach that. So naturally I thought he was just going through the motion of checking the fuel valve. Second, since we had practiced at least 2 prior engine out simulations, the student had at least some experience and had not shut the fuel valve in those simulated engine outs. Third, just before our flight, about half an hour earlier, the student asked me if ever we turned the fuel shut off valve off. I told him no, that we only shut the valve off in actual emergencys. The next day we went back to the plane and got it started. We plowed the snow so we had a suitable runway on the lake to takeoff which I did with no problems. In order to prevent another incident like this I believe I will need to check the fuel valve anytime a student's hands goes near the valve. This action may cause some students to think I have no confidence in them, but I can explain to them why I am doing it. Also, I could not allow a descent quite that low. The only problem there is that may not be a realistic training method. How can a student know how he or she would do in that situation if they only allowed to go to 500 or 1000 ft? I believe no regulations were broken. I know another pilot who flies off of that same lake, with skis, all winter. I took our safety into consideration when I decided to do the engine out and the fact that we, and the plane, came away without a scratch is proof. Also, there is a possibility that if we were any higher I still could not have restarted the engine and we would not have been able to land on the lake. We walked away safely and for that I am thankful, but this incident should still not be taken lightly.

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Original NASA ASRS Text

Title: A CFI WAS PRACTICING AN EMER LNDG, USING A FROZEN LAKE AS THE 'FIELD' OF CHOICE. THE STUDENT PLT TURNED OFF THE MAIN FUEL VALVE WITHOUT THE CFI REALIZING IT. THE CFI WAS UNABLE TO START THE ENG DURING PULL OUT AND AN ACTUAL EMER OFF ARPT LNDG WAS MADE ON THE LAKE.

Narrative: I AM A CFI. A STUDENT OF MINE AND I WERE FLYING AT 800 FT AGL WHEN I PULLED THE THROTTLE BACK TO IDLE TO SIMULATE AN ENG FAILURE. I ASKED THE STUDENT WHAT HE WOULD DO. THE STUDENT HAD BTWN 10-15 HRS TOTAL TIME -- NO SOLO. HE AND I HAD DONE AN ENG OUT TWICE BEFORE. THE STUDENT BEGAN A SIMULATED EMER APCH TO A FIELD. I POINTED OUT A FROZEN LAKE TO HIM, WHICH IS A BETTER CHOICE IN WINTER MONTHS IN MINNESOTA BECAUSE IT IS WELL KNOWN THAT EVEN 2 OR 3 INCHES OF ICE CAN SUPPORT TONS OF WT AND IT IS A LONG, FLAT SURFACE. WE CONTINUED THE EMER APCH BELOW 500 FT BUT STILL STAYED THOUSANDS OF FT AWAY FROM ANY PERSONS OR PROPERTIES (RURAL AREA). I TOOK THE PLANE'S CTLS MOMENTARILY (AFTER VERBAL) AND SHOWED THE STUDENT A SLIP IN ORDER TO MAKE HIS LNDG POINT. WE DSNDED TO PROBABLY 100-200 FT AGL AND I TOLD THE STUDENT TO ADD FULL PWR AND EXECUTE A CLB BACK TO 800 FT AGL. AFTER HE ADDED FULL THROTTLE, ABOUT 10 SECONDS LATER THE ENG SOUNDED LIKE IT WENT BACK TO IDLE. WHEN I LOOKED AT THE STUDENT'S HAND ON THE THROTTLE I SAW THE THROTTLE WAS APPLIED TO FULL, AND THAT IS WHEN I REALIZED WE HAD AN ENG FAILURE. IN MY EMER PROCS ACTIONS I IMMEDIATELY DISCOVERED THE FUEL SHUT-OFF VALVE WAS IN THE OFF POS. I TURNED THE FUEL SHUT-OFF VALVE BACK ON AND ATTEMPTED A RESTART WITH NO SUCCESS. AT ABOUT 20 FT ABOVE THE LAKE (WHICH WE WERE STILL OVER) I SHUT THE VALVE OFF, MIXTURE OFF, KEY OFF, AND MASTER SWITCH OFF AND EXECUTED A FORCED LNDG ON THE LAKE. NO DAMAGE WAS DONE TO THE PLANE NOR DID THE STUDENT AND I SUFFER EVEN THE SLIGHTEST INJURY. THE CAUSE OF THE INCIDENT IS OBVIOUS. DURING THE DSCNT, THE STUDENT SHUT THE FUEL VALVE OFF. WHEN I ASKED HIM WHY HE HAD SHUT IT OFF HE SAID HE WAS THINKING THAT IN AN ACTUAL EMER YOU WOULD SHUT THE FUEL VALVE OFF AND FOR SOME REASON HE ACTUALLY DID IT -- A MENTAL ERROR. WHY DID I NOT SEE HIM DO IT? IN A C150 THE FUEL SHUT OFF VALVE IS BTWN THE 2 OCCUPANT'S SEATS ON A VERT LEDGE. THE ONLY WAY TO CHK IT IS BY FEELING IT. THERE IS ABSOLUTELY NO WAY TO VISUALLY CHK THE VALVE WHILE SITTING IN THE AIRPLANE. THERE WAS ALSO NO REASON FOR ME TO THINK JUST BECAUSE HIS HAND WENT DOWN TO THE FUEL VALVE THAT HE WOULD SHUT IT OFF FOR A VARIETY OF REASONS. FIRST, I HAVE ALWAYS BEEN TAUGHT TO GO THROUGH MOTIONS OF CHKING THE SYS AND I TEACH THAT. SO NATURALLY I THOUGHT HE WAS JUST GOING THROUGH THE MOTION OF CHKING THE FUEL VALVE. SECOND, SINCE WE HAD PRACTICED AT LEAST 2 PRIOR ENG OUT SIMULATIONS, THE STUDENT HAD AT LEAST SOME EXPERIENCE AND HAD NOT SHUT THE FUEL VALVE IN THOSE SIMULATED ENG OUTS. THIRD, JUST BEFORE OUR FLT, ABOUT HALF AN HR EARLIER, THE STUDENT ASKED ME IF EVER WE TURNED THE FUEL SHUT OFF VALVE OFF. I TOLD HIM NO, THAT WE ONLY SHUT THE VALVE OFF IN ACTUAL EMERS. THE NEXT DAY WE WENT BACK TO THE PLANE AND GOT IT STARTED. WE PLOWED THE SNOW SO WE HAD A SUITABLE RWY ON THE LAKE TO TKOF WHICH I DID WITH NO PROBS. IN ORDER TO PREVENT ANOTHER INCIDENT LIKE THIS I BELIEVE I WILL NEED TO CHK THE FUEL VALVE ANYTIME A STUDENT'S HANDS GOES NEAR THE VALVE. THIS ACTION MAY CAUSE SOME STUDENTS TO THINK I HAVE NO CONFIDENCE IN THEM, BUT I CAN EXPLAIN TO THEM WHY I AM DOING IT. ALSO, I COULD NOT ALLOW A DSCNT QUITE THAT LOW. THE ONLY PROB THERE IS THAT MAY NOT BE A REALISTIC TRAINING METHOD. HOW CAN A STUDENT KNOW HOW HE OR SHE WOULD DO IN THAT SIT IF THEY ONLY ALLOWED TO GO TO 500 OR 1000 FT? I BELIEVE NO REGS WERE BROKEN. I KNOW ANOTHER PLT WHO FLIES OFF OF THAT SAME LAKE, WITH SKIS, ALL WINTER. I TOOK OUR SAFETY INTO CONSIDERATION WHEN I DECIDED TO DO THE ENG OUT AND THE FACT THAT WE, AND THE PLANE, CAME AWAY WITHOUT A SCRATCH IS PROOF. ALSO, THERE IS A POSSIBILITY THAT IF WE WERE ANY HIGHER I STILL COULD NOT HAVE RESTARTED THE ENG AND WE WOULD NOT HAVE BEEN ABLE TO LAND ON THE LAKE. WE WALKED AWAY SAFELY AND FOR THAT I AM THANKFUL, BUT THIS INCIDENT SHOULD STILL NOT BE TAKEN LIGHTLY.

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.