MIA04FA128 · Cessna R182

During a checkout flight by a certified flight instructor (CFI) with the operator in the accident airplane the day before, an excessive (200 rpm) decrease was noted when checking the right magneto. Maintenance cleaned the spark plugs, performed an engine run-up, and returned the airplane to service. The pilot passed the check out flight and was provided the airplane. The CFI reportedly advised the pilot that if there was any maintenance problem to have the airplane worked on and the maintenance cost would be deducted. The day before the accident the pilot flew the airplane to Milton, Florida, and landed uneventfully where the airplane remained overnight. No maintenance was performed or requested, and no fuel was purchased. The pilot and three passengers boarded the airplane for a local flight and three witnesses, one of whom is an A & P mechanic, reported hearing the pilot having trouble starting the engine. The engine ran rough after starting, and the airplane was taxied to the approach end of runway 36 where the pilot performed an engine run-up. Several witnesses including the A & P mechanic reported hearing a discrepancy during the magneto check. The pilot was heard increasing the engine rpm while at the engine run-up area. During the takeoff roll one witness reported that the engine was, "making sounds as if it was not developing power." Several witnesses noted the airplane did not become airborne until approximately 3/4 down the 3,700 foot-long runway, or approximately 2,828 feet down the runway. Conservative takeoff distances for ground roll and distance to clear a 50 foot obstacle per the airplane "Information Manual" were 910 and 1,745 feet, respectively. The airplane began climbing to an estimated height of 100 feet, and the landing gear was noted to retract. One witness reported the airplane flew over her position and the engine was heard to be running rough. A pilot who was flying in the area at the time observed the airplane turn onto the downwind leg, stall, then pitch straight down. The airplane crashed in the side yard of a residence located approximately .30 nautical mile and 303 degrees from the departure end of runway 36. Examination of the flight controls and power section of the engine revealed no evidence of preimpact failure or malfunction. The ignition harness was impact damaged which precluded testing. Examination of the heat damaged magneto revealed the left capacitor was shorted to ground consistent with heat damage, while the right capacitor was functional. Heat damaged components were replaced, the magneto was placed on a test bench and operated with no discrepancies noted. Examination of the impact and heat damaged carburetor revealed the accelerator pump piston seal was badly worn exposing most of the sealing spring; the worn seal would reportedly not result in increased fuel flow. The as found setting of the economizer would result in a leaner fuel/air ratio. Rust was noted in the drain cavity below the float bowl, on the inner portion of the carburetor bowl drain plug, and a small amount of debris was noted in the main bowl chamber. Documents provided by the operator indicate a discrepancy related to excessive rpm decrease during a magneto check on August 27, 2004. The spark plugs were removed, cleaned, rotated, and reinstalled.

Verbatim NTSB analysis and probable cause from the NTSB dataset