CEN16LA264

The sport pilot was conducting a personal cross-country flight in the experimental, amateur-built airplane. He reported that, during cruise flight, the engine began running roughly and that he then landed at a nearby airport to examine the engine. The pilot was not able to determine what caused the roughness. He started the engine and performed a run-up, which was normal, so he departed to continue the flight. While en route, the engine again started running roughly and subsequently experienced a total loss of power. The pilot chose to conduct a forced landing in a soybean field, during which he had to lower the pitch altitude to fly under power lines, which resulted in an increase in airspeed and subsequent hard impact in the field. A postaccident examination of the engine revealed no mechanical malfunctions or failures that would have precluded normal operation. The weather conditions at the time of the accident were not conducive for the accumulation of carburetor ice at cruise power.

On July 10, 2016, at 1205 eastern daylight time, an Alonso CH 701 airplane, N701ZG, collided with the terrain during an off-airport landing in Dexter, Michigan, following a loss of engine power. The pilot was not injured. The airplane was substantially damaged. The airplane was registered to and operated by a private individual under the provisions of 14 Code of Federal Regulations Part 91 as a personal flight. Visual meteorological conditions prevailed for the flight, which was not operated on a flight plan. The flight originated from Livingston County Spencer J Hardy Airport (OZW), Howell, Michigan about 1150.The pilot reported he departed from Howard Nixon Memorial Airport (50G), Chesaning, Michigan, and was flying to Ann Arbor Municipal Airport (ARB) when the engine began running rough. He landed at OZW to examine the engine with another pilot who was flying in an accompanying airplane. He stated they were not able to find anything wrong with the engine. The pilot started the engine and performed a run-up which he stated were normal, so he departed OZW to continue the flight to ARB. While en route, the engine once again started running rough and subsequently experienced a total loss of power. The pilot chose to land in a soybean field. During the forced landing approach, he saw power lines and had to lower the pitch altitude to fly under them. The airplane impacted hard in the soybean field. A postaccident examination of the airplane and engine was conducted by a Federal Aviation Administration (FAA) inspector along with an airframe and powerplant mechanic. The examination did not reveal any anomalies that would have resulted in the loss of engine power. The FAA Special Airworthiness Information Bulletin (SAIB) CE-09-35 "Carburetor Icing Prevention" chart indicated that the temperature and dewpoint, 79° F and 61° F respectively, were conducive for serious icing at glide power, not cruise power.