On October 16, 1999, about 1030 eastern daylight time, a Beech D35, N2109D, registered to Quality Computer Systems, Inc., was first observed resting in a ditch with the left wing separated just north of the Indiantown Airport, Indiantown, Florida. Weather conditions at the time of the accident are unknown and no flight plan was noted to be filed. The airplane was substantially damaged and pilot information is unknown. The date and time of the occurrence is unknown. On October 16, 1999, about 1030 hours, Detective Sergeant Ken Ault of the Martin County Sheriff Department was notified that cattle were on the runway at the Indiantown Airport. He responded and noted damage to a barbed wire fence and to three fence posts on the north end of the airstrip; the airplane was located in a drainage canal. The emergency locator transmitter was out of the attach bracket and was in the "off" position. Following recovery of the airplane, a set of aircraft keys was located on the back seat of the airplane. Subsequent investigation of the hangar where the airplane had previously been secured revealed no padlock and no damage to the hangar doors. The owner was contacted by the Detective who reported that the owner did not appear to be surprised when he was advised of the incident. The owner and the owner's brother refused to take polygraph tests when asked by representatives of the Martin County Sheriff Department. The owner of the airplane reported that he and another pilot flew the airplane from Michigan to Florida, on September 20, 1999. The owner flew back commercially to Michigan and returned to Florida, also flying commercially, on October 13, 1999. He last saw the airplane on October 14, 1999, about 0900 hours, at the Indiantown Airport where it was hangared. He flew commercially, returning to Michigan on October 14, 1999, instead of the previously scheduled flight on October 15, 1999. The reported purpose to fly out 1 day earlier was to avoid adverse weather that was scheduled to affect Florida. He further reported that no individual had his permission to fly the airplane. According to the owner, his medical certificate was being reviewed by FAA located in Oklahoma City, Oklahoma. Examination of the accident site by the FAA revealed ground tracks past the departure end of runway 31. Damage to a fence was noted past that location and the left wing was noted to be separated at the wing root; damage to trees was associated with the wing separation. The airplane then traveled up an embankment and into a ditch where the airplane was observed to be upright and partially submerged. On October 14, 1999, at 1107 local, one emergency locator transmitter (ELT) signal was received by one ground station. The ground station calculated the source of the ELT signal to be located from one of two locations, one of which was determined to be located 34 nautical miles and 046 degrees from the Indiantown Airport. According to personnel from the Indiantown airport, the owner's brother paid by check for hangar rental from September 22, to be vacated by October 15, 1999. The owner later stated to personnel from the airport that his brother was supposed to contact them regarding keeping the airplane beyond October 15, but that did not occur.