**This report was modified on 2/24/2016. Refer to the public docket for this accident for additional information.** the pilot's improper preflight planning and his decision to depart with known landing gear system mechanical deficiencies, which resulted in a forced landing during a partial loss of power on one engine. Factors related to the accident were the fatigue failure of an engine cylinder barrel, the inadequate manufacturing process of the cylinder barrel, and the pilot's inability to retract the landing gear.