Accident Overview
On August 31, 2015, at approximately 1230 central daylight time, a Cessna T240 airplane, registration N452CS, made a forced landing after departing from West Houston Airport (IWS), Houston, Texas. The aircraft was on an instructional flight under 14 Code of Federal Regulations Part 91. Visual meteorological conditions prevailed and an instrument flight rules flight plan had been filed. The flight instructor and private pilot receiving instruction were not injured. The airplane sustained substantial damage.
Pilot Reports
According to the flight instructor, they had completed instrument flight rules training and three full-stop landings. On the final takeoff, at about 300 ft above ground level, the engine experienced a total loss of power. The instructor took control and executed a forced landing to a field beyond the departure end of the runway. The airplane landed and continued into trees, where it came to rest upright with the right main landing gear collapsed. The instructor secured the airplane and called for assistance using a handheld radio.
Before the flight, the fuel tanks were filled to capacity (102 usable gallons). Preflight inspection showed no contaminants. During the flight, both pilots switched the fuel selector to maintain fuel balance. Before the final takeoff, fuel gauges indicated 20 gallons left and 21 gallons right. No crew-alerting system warnings were noted. The flight lasted 1.81 hours; at an average fuel consumption of 30 gallons per hour (gph), the instructor calculated about 54 gallons consumed and 48 remaining.
Post-Accident Findings
Law enforcement secured the scene. Fuel was observed leaking from the right wing fuel vent; a plug was placed to stop leakage. The amount of fuel that leaked from the right tank was unknown. The responding FAA inspector noted that after the accident, the fuel selector knob was in the left OFF position and the emergency fuel pump was ON. It could not be determined when the emergency pump was switched ON.
FAA air traffic control data showed the airplane departed at about 0953, canceled IFR at 1151, and the accident occurred about 39 minutes later—a total flight time of about 2.5 hours. Using the instructor’s fuel consumption rate, about 75 gallons would have been consumed, leaving 27 gallons.
Engine Tests
On September 10, 2015, three engine test runs were conducted under FAA supervision. The Continental Motors engine remained attached to the airframe with no significant damage. The accident propeller was replaced. Engine oil level was 5 quarts. With the master switch ON, the left fuel quantity gauge indicated 0 gallons, right indicated 25 gallons. All runs used remaining fuel in the right tank (since left tank was empty).
First run: engine warmed, magneto check normal, power increased to 25 inches of mercury manifold pressure (MAP), then full power. As throttle was reduced, a propeller pitch oscillation was noted. The engine was shut down normally.
Second run: magneto check and propeller cycle performed, engine advanced to max power. No oscillation during throttle reduction. Power set to 25 in.Hg MAP and electric boost pump actuated; the engine subsequently lost all power.
Third run: engine at 25 in.Hg MAP, fuel selector moved to LEFT tank position; within one minute, total loss of power occurred. Digital instruments and crew-alerting system functioned normally. Examination revealed no anomalies precluding normal operation.
The pilot’s operating handbook states that if the emergency fuel pump switch is turned ON with the engine-driven fuel pump operating normally, total loss of engine power may occur. The engine manufacturer noted that at high power, the engine can generally handle extra fuel from the emergency pump, but at lower power settings, loss of power is more likely.