Beech 36 N66FN accident near Cincinnati, Ohio

Probable cause

A loose fuel inlet fitting on the fuel pump due to improper maintenance, which resulted in a total loss of engine power.

NTSB analysis

During a descent to his destination, the pilot noticed an "unusual" vibration. After checking the engine analyzer, he noticed that one of the engine cylinders was not producing an exhaust gas temperature (EGT) reading. A few moments later, another cylinder EGT dropped offline, then a third cylinder. Cylinder EGTs continued to drop offline then the engine "quit." The pilot maneuvered the airplane over a populated area and landed on a roadway. Upon landing, the airplane struck obstacles along the roadway and came to rest underneath a concrete overpass. The wings and fuselage sustained substantial damage.

Examination of the engine revealed that both the fuel inlet and fuel return line fittings on the fuel pump were loose and could be turned by hand. No adjacent impact damage was noted around the loose fittings. The fuel pump had been removed and replaced 2 days prior to the accident. The loose fuel inlet fitting likely resulted in the loss of engine power.

Text from the NTSB. Open the NTSB docket for CEN20LA148 for the full record.