Accident Overview
On June 3, 2014, at about 1515 central daylight time, a Cessna 172N, registration N734BY, sustained substantial damage when it nosed over during a forced landing near North Padre Island, Texas. The pilot, who was the sole occupant, was not injured. The aircraft was operated by an individual under 14 CFR Part 91 as a personal flight. Visual meteorological conditions prevailed, and no flight plan was filed. The flight originated from David Wayne Hooks Memorial Airport near Houston, Texas, and was destined for Port Isabel-Cameron County Airport, Port Isabel, Texas.
Pilot Report
The pilot reported that while in cruise flight at 8,500 feet above mean sea level, the engine began running rough. He suspected carburetor ice or an overly lean fuel-air mixture, so he applied carburetor heat and set the mixture control to full rich. The engine continued to run rough. He then attempted to switch fuel tanks and cycled the ignition switch to test the magnetos, but the engine continued running rough at reduced power. The airplane had approximately twice the required amount of fuel for the flight. When all efforts to restore engine power failed, the pilot executed a forced landing on an island. During the landing, the tires sank into soft sandy soil. Once the nose landing gear tire touched down, it sank, and the airplane nosed over.
Weather Conditions
Weather near the accident site included a surface temperature of 32 degrees Celsius and a dew point of 21 degrees Celsius. Radiosonde data from NOAA indicated that at the airplane's cruising altitude, the temperature was about 17 degrees Celsius and the dew point about 3 degrees Celsius. According to a carburetor icing probability chart, the surface conditions were in a range of susceptibility for light icing at cruise and descent power settings. The altitude conditions were in a range of susceptibility for moderate carburetor icing at cruise power settings and severe carburetor icing at descent power settings.
Post-Accident
Due to the location of the accident site, an on-scene examination of the airplane was not possible. Miscommunication between interested parties resulted in the airplane being released before an FAA or NTSB postaccident examination could be conducted after it was recovered. An Aircraft Owners and Pilots Association flight training publication notes that when carburetor heat is applied to melt ice, the engine may run rougher due to additional fuel enrichment, and the mixture may need to be leaned to achieve a burnable fuel-air mixture.