On June 28, 1995, at 0800 Alaska daylight time, a wheel equipped Cessna 208 airplane, N9825F, registered to Cessna Finance Corporation of Wichita, Kansas, and operated by TransNorthern Aviation Inc. of Talkeetna, Alaska, struck some trees during maneuvering flight while performing aerial survey work, approximately 20 miles northwest of Talkeetna. The aerial survey flight, operating under 14 CFR Part 91, departed Talkeetna on a company visual flight rules flight plan for a local flight. Visual meteorological conditions prevailed. The airline transport certificated pilot, and the two passengers were not injured. The airplane was substantially damaged. According to the pilot, they were surveying between two Global Positioning System (GPS) points and it was important for the airplane to be in level flight at 80 knots for 4 minutes prior to reaching the initial survey point. The pilot stated he positioned the airplane close to the Peters Hills to begin a survey run. The flight path was north and he was planning a right turn. The pilot stated he looked to the right and felt he would clear all the obstacles. He began his right turn, then looked inside the cockpit to make a power adjustment. When he glanced up again he noticed that he would not be able to clear a very tall tree located on the ridge line directly off the nose of the airplane. The pilot stated that he did not feel he could pull up because of the 80 knot airspeed and low power setting. He attempted to maneuver the nose of the airplane so the tree would pass off the left side of the airplane. The right wing struck some trees. The pilot could not see any damage to the wing, however, the outer 4 feet of the right wing were obscured by the radar pod. The leading edge of the wing and a section of the main spar, outboard of the radar pod, was damaged. The damage to the airplane was found during the postflight inspection. According to 14 CFR Part 135.1,b,4,iii, aerial photography or aerial survey is exempted from 14 CFR Part 135. According to the Director of Operations, the pilot submitted to a toxicological test as soon as this mishap was determined to be an accident. He stated the results of the test were all negative.