N1254DCessna 172S · 2006

The private pilot and the flight instructor had been practicing emergency engine-out procedures in preparation for the private pilot’s commercial checkride. The pilot stated that he just completed the emergency procedure for a simulated engine fire, which evolved into a simulated loss of engine power. He entered a steep spiral over the airport from 2,500 ft mean sea level (msl) to lose altitude and entered the left downwind leg of the traffic pattern at 1,200 ft msl. The private pilot said that while turning from downwind to base, the flight instructor suddenly took control of the airplane because the engine oil temperature annunciator illuminated. The flight instructor made a sharp turn onto final approach and declared an emergency. The airplane was high, so the flight instructor extended the flaps and performed a maximum forward slip to lose altitude. The airplane touched down more than halfway down the 2,600-ft-long turf runway before contacting a ditch, and then nosed over. The airplane’s vertical stabilizer/rudder and a wing strut were substantially damaged during the accident sequence.

The pilot said the engine never lost power and was operating right up until impact. The flight instructor said he had experienced an emergency about three months prior to the accident due to a cracked engine case, during which the engine was loud and would vibrate when he applied full power. He said he did not want to add power to go-around because he was concerned that he was dealing with similar scenario or that the engine would catch fire due to the high oil temperature.

A postaccident test-run of the engine was conducted utilizing the airplane’s existing fuel and oil systems. The engine started immediately, and all engine parameters were normal. A separate functional test of the oil temperature probe revealed that it operated within normal range. No mechanical deficiencies were noted with the engine that would have precluded normal operation.

According to flight data downloaded from the airplane’s digital avionics, each time the throttle was decreased to idle while performing the engine out simulations, there was a progressive increase in oil temperature. As such, it is most likely that the engine did not have time to cool down in between each engine-out simulation and the oil temperature gradually increased until the annunciator came on.