What happened
On June 13, 2012, at approximately 1915 Alaska daylight time, a de Havilland DHC-2, registration N121KT, was conducting a visual flight rules (VFR) sightseeing flight departing from Talkeetna Airport (PATK) in Alaska. The flight was being operated by Rusts Flying Service (doing business as K2 Aviation) under Part 135 regulations.
After departing runway 18 and reducing power to a cruise climb setting, the engine began running rough at approximately 1,200 feet above the ground. The pilot attempted to return to PATK and performed emergency procedures to restore power; however, the engine continued to run poorly at reduced power. The aircraft was unable to maintain altitude and suffered a total loss of engine power.
The pilot performed a forced landing on a sand bar along the Chulit . Upon impact, the aircraft bounced over logs and ditches, resulting in substantial damage to the main landing gear, empennage, elevators, and horizontal stabilizer. The pilot and six passengers were not injured.
The investigation
An FAA inspector examined the aircraft in Talkeetna on June 14, 2012. The inspection of the engine revealed that the number two cylinder head had cracks radiating from the spark plug hole throughout the head, and the component had begun to separate from the cylinder base.