ATL82DA126

Factual narrative

DURING FLIGHT THE AIRCRAFT ENGINE DEVELOPED A NOISE WHICH THE PILOT DESCRIBED AS A HISSING. THE PILOT DECLARED AN EMERGENCY, WAS VECTORED TO THE NEAREST AIRPORT, AND PROCEEDED TO SHUT OFF THE ENGINE AT 5000 FEET WHEN OVER THE AIRPORT. DURING THE FORCED LANDING THE AIRPLANE WAS FLOWN BENEATH ELECTRICAL TRANSMISSION WIRES LOCATED NEAR THE RUNWAY THRESHOLD AND IMPACTED APPROXIMATELY 200 YARDS SHORT OF THE RUNWAY. APPROXIMATELY 1/2 INCH OF THE NUMBER 1 EXHAUST RISER WAS FOUND ATTACHED TO THE CYLINDER WITH THE REMAINDER LYING IN THE ENGINE COWL LOWER SECTION. EXAMINATION REVEALED SOOT DEPOSITS ON THE ENGINE COWL ADJACENT TO THE NUMBER 1 ENGINE EXHAUST RISER. A LIGHT BROWN DISCOLORATION WAS OBSERVED ON THE NUMBER ONE CYLINDER LOWER SPARK PLUG AND THE FRACTURE SURFACES OF THE SEPARATED NUMBER 1 EXHAUST RISER. THE PIPER AIRCRAFT CORPORATION INDICATED THAT MISALIGNMENT OF THE CYLINDER HEAD COULD RESULT IN A CRACKED STACK ASSEMBLY IMMEDIATELY BELOW THE STACK ASSEMBLY FLANGE. Source: NTSB Aviation Accident Database (Pre-2008 Archive) Retrieved: 2026-02-12