Shortly after takeoff on an extended crosswind leg about 800 feet mean sea level, the RV-4’s engine lost total power.
The pilot continued ahead and landed in a field near Butler, Pennsylvania. During the landing, the plane hit a wire fence and brush, which resulted in substantial damage to the fuselage and wings.
During post-accident interviews, the pilot reported that this was the first flight after he had made maintenance repairs to the automobile-converted engine due to an engine failure one month before the accident. He stated that he installed an aftermarket engine control unit and modified the fuel delivery software, which resulted in the engine running too lean for flight and likely caused detonation and piston damage to occur.
During the run-up before the accident flight, he was aware that the engine was not producing power as it should. However, he decided to depart with a known engine problem, and his decision to do so led to the accident.
Probable cause: The pilot’s improper decision to fly the airplane with a known engine problem and his improper modification of the engine control unit fuel delivery software, which led to the engine running too lean and resulted in a total loss of engine power during climb.
NTSB Identification: ERA18LA163
This June 2018 accident report is provided by the National Transportation Safety Board. Published as an educational tool, it is intended to help pilots learn from the misfortunes of others.
A wise person once said, “If it does not work correctly on the ground it is unlikely it will work any better in the air.” This guy was an accident looking for a place to happen. He does not seem to fully appreciate the Experimental category that the aircraft was operated under. To begin with there was no mention of why the engine had failed previously such that it required such extensive repair or what he did to prevent a reoccurrence. And then there is the question of why he switched to the aftermarket ECU along with fiddling around with its standard programming (was it even for that type engine?). Was that new Modified ECU more experimenting or an attempt to correct what caused the engine to fail previously? It all seems like he was not taking a careful and measured approach to running a non-standard powerplant in his aircraft. I do not know if there are very many (or any) other RV-4’s out there with that same GM engine setup so he could be working on a one of a kind setup that does not have any good examples to follow and that is when an abundance of caution is needed.
Actually, the NTSB did list that he effectively overhauled the engine replacing the pistons. One of them had a hole burned in it.
Then, he was test flying this plane as it was the first flight after maintenance.
What we do not know is why it did not produce max power on the ground, and what caused it to run lean enough to detonate and wreck the engine again.
Also, your observation on not making proper power on the ground is correct. If he could not get the projected max static RPM on the ground, he probably should not have taken off.
This guy should not be able to get insurance. A. running an auto engine B. running the engine again after a failure only a month before without a complete and total checkout C. departed KNOWING the engine was not right.