Cessna 310 N2625H

A 3,800-hour commercial pilot departed on a personal cross-country flight in a light piston powered, twin-engine airplane. Shortly after take-off, the pilot reported to the controller that "[he] found a problem and that he wanted to check it out on the ground". The pilot stated that, he was heading back to the departure airport. The air traffic controller offered the pilot, a straight-in approach to the airport. The pilot declined, and stated that he would do a [normal] downwind to the runway. During the conversation with the controller, the pilot did not disclose the nature of the problem. The airplane crashed approximately 4 miles prior to reaching the airport, in a vacant lot. Radar data revealed the airplane departed the airport and flew the runway heading. When the airplane was approximately 5 miles from the airfield and approximately 5,000 feet mean sea level (msl), altitude, the airplane initiated a turn to the right. The airplane continued with a 180-degree turn and then proceeded in a straight line. During the return flight back to the airfield, radar showed the airplane gradually descending while at a ground speed of 170 knots. The last radar hit showed the airplane at 2,700 feet, at a ground speed of 160 knots. The wreckage of the airplane was examined at the accident site on January 11-12, 2007. A post-impact fire consumed part of the airframe cabin. All major components of the airplane were accounted for at the scene. The airplane was found to have impacted the ground in a near nose-down (vertical) attitude. The airframe was extensively crushed by the impact, in an "accordion" style-crushing nose to tail. The wings remained attached to the airplane and perpendicular to the fuselage; both engines were driven several feet into the ground. Control continuity to all flight controls was established. The landing gear was in the retracted position. The flap drive mechanism was located and corresponded to a flap setting of approximately 30 degrees. Post examinations of the engines and propellers were conducted. The left engine sustained heavy impact damage to the front of the engine, and included a crack in the engine's crankcase. Both magnetos separated from the engine during the accident sequence; the magneto's had heavy impact damage and would not produce a spark. Sparkplugs in the left engine were removed and examined. When compared to the Champion Aviation Check-a-Plug Comparison card, the sparkplugs were worn out normal. The top sparkplugs had light gray deposits and the bottom sparkplugs were oily in the electrode areas. No anomalies were noted with the fuel pump or oil pump. The engine was disassembled, and no pre-impact abnormalities with the engine, cylinder assemblies, or engine components were found. The right engine also sustained heavy impact damage. Both magnetos, which separated from the engine during the crash, produced spark. The sparkplugs had similar appearances to the ones installed in the left engine. During the disassembly of the right engine, no pre-impact abnormalities with the engine, cylinder assemblies, or engine components were found. During the accident sequence both propellers remained attached to their respective engine. The propeller blades on both engines were "wrapped" aft to the engines. Examination of the propellers revealed that neither propeller was feathered at the time of impact. Three of the four propeller blades had extensive nicks and gouges along the leading edge.

Quoted verbatim from the NTSB record.