What happened
On August 22, 2016, at approximately 08:05 a.m., a Piper PA-32-300 Cherokee Six, registration HI-482, was conducting a commercial flight from Punta Cana International Airport to Arroyo Barril Airport. Minutes after departing Punta Cana, the aircraft experienced a significant loss of engine power.
In response to the power loss, the pilot performed an emergency landing on the Bulevar del Este, near the Macao intersection in the province of La Altagracia. While the 5 occupants on board the aircraft remained uninjured, the sudden appearance of the aircraft caused a motorcyclist traveling on the highway to lose control. The motorcyclist sustained serious injuries due to a fall and impact with the pavement, but the aircraft did not strike the third party.
The investigation
The CIAA investigation focused on the mechanical state of the Lycoming IO-540-K1A5 engine and the circumstances of the flight. Investigators examined the engine components, specifically inspecting the spark plugs and the cylinder heads. The investigation confirmed that the aircraft's airworthiness documentation was up to date, with the last 100-hour inspection having been completed in May 2016.
Findings
- The engine failure was caused by a loss of compression and an oil leak through the exhaust valves of cylinders #3 and #6.
- The loss of compression led to a significant drop in engine RPM.
- The pilot successfully followed manufacturer-established emergency procedures to execute a controlled landing.
- Weather conditions at the time of the event were considered favorable for flight operations.