(AP) -- The National Transportation Safety Board says lack of fuel probably caused a fatal 2009 Spartanburg County plane crash.

Authorities say 64-year-old Stuart Adcock Jr. of Campobello, S.C., was killed on April 7, 2009, when his single-engine 1974 Grumman American AA-1B crashed in a pasture.

In a Dec. 20 report, the NTSB concluded the engine died because it was not getting enough fuel, due to inadequate planning and failure to maintain air speed while making a forced landing.

The investigation found the fuel tanks were drained.

The report said the pilot had both over-the-counter and prescription medicines in his system but investigators could not determine whether he was impaired at the time of the accident.

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