ERA21LA361 · Beech C24R

The chief flight instructor of the flight school was performing a checkout flight for two other flight instructors, one of whom was in the front right seat and conducted the short-field takeoff. During the takeoff roll, the airplane lifted off in about 2,000 ft, leaving about 6,000 ft of runway remaining. Shortly after liftoff, the airplane failed to maintain airspeed or altitude upon reaching an altitude of about 150 ft above ground level. The chief flight instructor took control of the airplane and attempted to land on the remaining runway; however, the airplane struck the approach lighting system, flipped over, and came to rest inverted in a marsh. Examination of the engine revealed that two fuel injector lines were not installed properly: one contained a damaged nut and was pulled off the injector with ease, and the other was secured by only one thread. In addition, the oil filter screen was contaminated with large pieces of carbon and metal. These discrepancies should have been detected and addressed during the previous annual/100-hour inspections that occurred 5 flight hours before the accident flight. Based on this information, it is likely that condition of one or both of the fuel injector components allowed air to be introduced into the fuel stream for their respective cylinders, thus reducing the engine performance and resulting in a partial loss of power during the initial climb.

Verbatim NTSB analysis and probable cause from the NTSB dataset