FTW04LA109 · Spannagel RV-8A

The homebuilt airplane landed short of Runway 21 following a loss of engine power after takeoff. The 355-hour private pilot/owner/builder reported that prior to takeoff he pulled into the run-up area and "checked all conditions....and all indications [were] positive." The takeoff was normal until he reached an altitude of 1,200 AGL, when he noticed an increase in oil temperature. The pilot leveled the airplane, and initiated a left crosswind turn, followed by a downwind turn in the traffic pattern. The oil temperature continued to increase toward the red-line mark on the gauge. When the airplane was on the downwind leg, engine power decreased and he was unable to maintain altitude. The pilot extended the flaps to 20 degrees and turned onto a short final approach for Runway 21. The airplane impacted terrain approximately 100 feet short of the landing threshold. Subsequently, the landing gear collapsed, and the airplane nosed over, slid for approximately 100 feet, and came to rest in an inverted position at the threshold of Runway 21. Continuity was established for the engine controls and fuel system, and honey-colored oil had exited the carburetor and had pooled around the engine area. The engine oil and engine oil filter were changed approximately 1-hour before the flight. The new Chevrolet V6 4.3 liter liquid cooled automotive engine had accrued a total of five hours at the time of the accident. A normal amount of engine coolant was also observed. Further examination of the engine by the pilot/owner/builder, revealed that the main bearings and connecting rod bearings were partially seized on the engine, and that the clearances between the journals and the bearings were too tight. The bearings exhibited chafing.

Verbatim NTSB analysis and probable cause from the NTSB dataset