Primary finding
Probable cause
The pilot’s inadequate fuel management, which resulted in fuel starvation and a total loss of engine power. Contributing to the accident was the inaccurate fuel gauge.
Investigator assessment
Analysis narrative
The pilot stated that the left wing fuel tank contained 3 gallons and the right wing fuel tank contained 4 gallons of fuel before departing on the accident flight. The pilot said he determined the fuel quantities during the prefight from fuel quantity gauge indications and by looking into each fuel tank to see if it was wetted with fuel. The pilot departed, performed one touch-and-go landing, then flew about 3 miles west, where he performed two steep turns before returning to the airport. The pilot reported that, while on the downwind leg of the traffic pattern, the left wing fuel quantity gauge indicated 2 gallons, the right wing fuel quantity gauge indicated 3 gallons. While on final approach for landing, about 250-300 ft above ground level (agl) the engine lost total power. The pilot switched fuel tanks, but the engine did not regain power. The pilot performed a forced landing about 300 to 400 ft short of the runway, resulting in substantial damage to the airplane. Postaccident examination revealed that the left wing fuel tank was empty and the right tank contained about 1 ½ gal of fuel. No fuel was present at the carburetor jets or the fuel supply line to the carburetor. The lack of fuel in these locations is consistent with a loss of engine power due to fuel starvation. It is likely that the engine could not be restarted immediately due to air within the fuel system. Testing of the left wing fuel tank quantity gauge found the gauge was inaccurate, likely due to the presence of corrosion within the gauge assembly. Examination of the engine revealed no mechanical anomalies that would have precluded engine operation.
Source record
Factual narrative
On November 6, 2024, about 1555 central standard time, a De Havilland DHC-1, N420TD, was involved in an accident near East Troy, Wisconsin. The airplane sustained substantial damage. The private pilot received minor injuries. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight. The pilot stated that, during his preflight inspection, there were 3 gallons of fuel in the left wing fuel tank and 4 gallons of fuel in the right wing fuel tank. He stated that the airplane had a fuel capacity of 9 gallons per wing tank. The pilot said that he determined the fuel quantity in each tank by looking at the fuel gauges and looking into each fuel tank to see if it was wetted. The pilot departed, performed one touch-and-go landing at the airport, and then flew about 3 miles west, where he performed two steep turns. He returned to the airport, and while the airplane was on the downwind leg of the traffic pattern for landing, the left wing fuel tank quantity gauge indicated 2 gallons and the right wing fuel tank quantity gauge indicated 3 gallons. While on final approach for landing at an altitude of about 250 to 300 ft agl, the engine lost total power. The pilot changed the fuel tank selector, but the engine did not regain power. The pilot performed a forced landing about 300 to 400 ft short of the runway, resulting in substantial damage to the wings and fuselage. Postaccident examination of the airplane revealed that the fuel selector was in the right wing fuel tank position. The airplane was equipped with direct-reading fuel gauges at the inboard left and right wing, adjacent to each wing fuel filler port. Both gauges indicated zero at the accident site. The left wing fuel tank was empty, and the right wing fuel tank contained about 1 ½ gallons of fuel. No fuel leaks were present in the left and right fuel tanks. No fuel was present at the carburetor jets or the fuel supply line to the carburetor. The wing fuel tank vents and the fuel selector valve had no anomalies that would have precluded normal operation. While testing the fuel tank quantity gauges for accuracy, the left wing fuel tank quantity gauge indication was stuck at 3 gallons when fuel was introduced, and it remained at 3 gallons as the fuel quantity was altered. Examination of the left fuel tank quantity gauge assembly found that it was corroded. The right wing fuel tank quantity gauge was accurate during testing. Examination of the engine revealed no mechanical anomalies that would have precluded engine operation.