On August 31, 2010, about 0815 eastern daylight time, an Aero Commander 560E, N175SP, operated by a private individual, was substantially damaged during a forced landing, after experiencing a total loss of engine power in both engines during the initial climb after takeoff from the Herlong Airport (HEG), Jacksonville, Florida. The certificated private pilot and a certified flight instructor (CFI) were not injured. Visual meteorological conditions prevailed and no flight plan had been filed for the flight destined for Craig Municipal Airport (CRG), also located in Jacksonville, Florida. The personal flight was conducted under the provisions of 14 Code of Federal Regulations Part 91. During an interview, the pilot reported that he purchased the airplane on June 19, 2010. The airplane was previously owned by the Delaware State Police, and had not been flown for over 1 year. On July 23, 2010, after maintenance which included an annual inspection, the pilot took delivery of the airplane in Delaware, and flew it to HEG. The purpose of the accident flight was to fly to CRG for avionics related maintenance. The pilot performed a preflight inspection, which included checking the fuel tanks for water contamination, prior to the flight. The pilot and CFI, who the pilot considered a safety pilot per insurance requirements, departed without incident. The airplane was in a climb between 1,500 and 2,000 feet mean sea level, when the left engine lost all power. The pilot successfully feathered the engine; however, shortly thereafter, the right engine began to "sputter" and also lost all power. The pilot was unable to restore engine power in either engine, and performed a forced landing to Interstate I-10. During the landing, the airplane struck trees, which resulted in substantial damage to both wings and the fuselage. The CFI reported that he assumed control of the airplane immediately after the left engine failed. He secured the left engine and subsequently maneuvered the airplane for the forced landing. He noted that both engines "surged" several times prior to losing power. While on approach, he observed power lines which necessitated lowering the airplane's nose, and increased the touchdown airspeed. During the landing roll, the airplane's right tire departed the paved surface, and the airplane veered into trees, toward a fence. The airplane was subsequently removed from the accident site for further examination, which was conducted by Federal Aviation Administration (FAA) inspectors. Examination of the airframe and both engines did not reveal any mechanical malfunctions. It was noted that fuel drained from the airplane's fuel tanks prior to its removal from the accident site was contaminated with water. The inspector drained a 1.5-gallon fuel sample, which revealed approximately 2 cups of water. The pilot further reported that the airplane had been operated for about 24 hours since it was purchased, and was last flown on August 11, 2010. At that time, fuel was added to the airplane which brought the total fuel on board to approximately 80 gallons in the main fuel tanks, and 20 gallons in the auxiliary fuel tanks. The pilot reported 242 hours of total flight experience, which included about 90 hours in multiengine airplanes, of which 24 hours were accumulated in the accident airplane. The CFI reported 1,474 hours of total flight experience, which included about 375 hours in multiengine airplanes, of which 10 hours were accumulated in the same make and model as the accident airplane.