On October 2, 1997, at 0605 central daylight time, a Beech E18S, N916TM, operated by May Air Express, collided with the terrain during takeoff on runway 31 (2,850' x 75') at the Lake Elmo Airport, Lake Elmo, Minnesota, while on a 14 CFR Part 91 positioning flight. The airplane was substantially damaged. Neither the pilot nor the pilot-rated passenger on board were injured. Visual meteorological conditions prevailed. The airplane was being flown to Minneapolis, Minnesota, to pick up a cargo load when the accident occurred. The airplane lifted off at 70 knots. He reported he allowed the airplane to accelerate in ground effect for several seconds after which time the airplane became "... unstable in the roll axis." He reported he added power as there was not enough runway left to land on. The airplane was 3/4 the way down the runway when the left wing tip touched the runway. He reported that at this point he added more power at which point the left wing tip contacted the terrain off the left side of the departure end of the runway causing the nose to pitch up. He then reduce the power to idle and the aircraft touched down in the grass collapsing the landing gear. The pilot stated that the airplane normally lifts off between 70 and 75 knots when it is light. In addition, he stated that the engines sounded normal during the accident sequence. An inspector from the Minneapolis, Minnesota, FAA Flight Standards District Office reported that another Beech 18 had taken off on the same runway, but in the opposite direction of N916TM less than one minute prior to the accident.