On January 28, 2005, at 1700 central standard time, a Cessna 310J twin-engine airplane, N3138L, was substantially damaged when the landing gear collapsed after touchdown at the Crosbyton Municipal Airport (8F3) near Crosbyton, Texas. The instrument rated private pilot, the sole occupant of the airplane, was not injured. The airplane was registered to and operated by the pilot. Visual meteorological conditions prevailed, and no flight plan was filed for the 14 Code of Federal Regulations Part 91 business flight. The cross-country flight originated from the Kent County Municipal Airport (22F) around 1615 with an intended destination of Lubbock, Texas. The 830-hour pilot reported in the Pilot/Operator Aircraft Accident Report (NTSB Form 6120.1/2), that the main cabin door opened just after takeoff. He then decided to return to 22F, land and secure the door. After extending the landing gear, he checked the landing gear position lights for agreement. The lights indicated that the gear was not extended and locked down. The pilot aborted the attempt to land at 22F and decided to continue onto Lubbock where more assistance would be available. En-route to Lubbock, the pilot was attempting to hold the cabin door closed and address the gear problem as well. His right arm became fatigued, and he then decided to declare an emergency. Lubbock approach control vectored the airplane to the nearest airport at Crosbyton, Texas, approximately seventeen miles away. En-route to Crosbyton, he attempted to manually extend the gear using the emergency gear extension crank. Allthough he believed the gear was extended, he still failed to achieve a safe gear indication. Upon arrival at 8F3, the pilot set up for a landing on runway 35. Just before touchdown, the pilot released his grip on the cabin door. The door swung almost fully open. The airplane rolled to the right, striking the right wing-tip on the pavement. The pilot corrected to the left, and impacted the runway hard, collapsing the landing gear. The airplane slid off the runway to the left, coming to rest in a field adjacent to the runway. According to an FAA inspector, who examined the airplane at the accident location, the airplane sustained damage to the landing gear, landing gear doors, belly skin and both propellers. The right engine mounts sustained structural damage. The right fuel tank was also ruptured.