FTW83FA252

Witnesses reported that when the acft was stabilized on final apch, it pitched up slightly & yawed, then rolled left to an inverted attitude & crashed in a canal. Several witnesses stated that the left prop was windmilling. One stated the left prop had stopped. Two others said smoke was trailing from the acft. One witness stated that after the acft passed over his car, a fine mist of oil fell on his windshield. When the acft was recovered from the canal, the left prop was found in the feathered position while the right prop was near its low pitch stops. The left prop dome was found depleted of air pressure & no oil was found in the left eng case. Also, an oil film was found on the bottom of the left eng, left flap & left stabilizer. A further exam revealed that an oil interconnect line, Piper pn: 920024-811, had failed inside its fire proof covering. The hose was 8 yrs old, its recomended replacement interval was 5 yrs. It hadbeen installed with a small bend radius. Also, the left eng had evidence of heat & wear due to lack of oil.