On December 23, 1999, about 1045 Alaska standard time, a tundra tire equipped Cessna 185 airplane, N70021, sustained substantial damage when it nosed over during takeoff from an off airport beach on Montague Island, Alaska, at 59 degrees 55 minutes north latitude, 147 degrees 30 minutes west longitude. The commercial pilot, and the two passengers on board were not injured. The flight was operated by Bear Lake Air Service, of Seward, Alaska, under 14 CFR Part 135. The on-demand air taxi flight was returning the two passengers to Seward from a hunting cabin. Visual meteorological conditions prevailed at the time of the accident, and a company VFR flight plan was filed.

The owner of the company, and the accident pilot, both told the NTSB investigator-in-charge (IIC) that the retrieval of the passengers had been delayed for five days due to bad weather. Both men told the IIC that they were concerned that if the passengers were not picked up, and the weather deteriorated, it could again be several days before they could be retrieved.

During a telephone interview with the NTSB IIC on December 23, the pilot of a second company airplane, who was in the area when the accident occurred, and was in communication with the accident pilot, said winds were light and variable, and the tide was coming in. When the accident pilot had not reported airborne to him 10 minutes after he said he was taking off, the reporting pilot returned and saw the airplane inverted in the surf. He related that all three occupants were out of the airplane, and had returned to the cabin for shelter.

The pilot wrote in his NTSB Pilot/Operator Report, that he waited on the ground about 45 minutes for the passengers to collect their equipment. He said the incoming tide was to be very high, but he estimated the available beach to be 50 feet wide when he began his takeoff roll. According to the pilot, an incoming wave washed over the takeoff area in front of the airplane. He wrote that the airplane was "too slow to fly, and too fast to stop." He indicated he rotated the airplane off the ground and applied more flaps in an attempt to takeoff over the incoming water. The airplane settled, the wheels contacted the water, and the airplane nosed over.