Occurrence
The pilot of an airplane reported encountering propeller RPM problems during flight. This issue deteriorated the airplane's climb performance. The pilot elected to land in a rough, uneven field. Ground witnesses reported that the airplane staggered into the air in ground effect and then crashed.
Witness Observations
Upon arrival at the accident site, witnesses observed that the airplane's wings, fuselage, and empennage were covered with ice. The ice appeared to have melted and refrozen.
Pilot Report
The pilot reported that he had removed ice from the airplane before departing. Despite this preflight action, ice was present on the airframe after the accident.