Incident Overview
During an aerial survey operation, the pilot was required to fly straight and level for four minutes before reaching the first survey fix. While maneuvering the airplane close to hills, the pilot needed to cross a ridge line while turning to get on course.
Pilot Actions
The pilot looked at the ridge line and determined that the airplane would clear the ridge and all obstacles. He then started the turn and looked inside the cockpit to make a power adjustment. When he looked up again, he saw that the airplane would not clear a tall tree on the ridge line directly in front of the airplane's nose.
Collision
To avoid the tree, the pilot turned the airplane to the right. During this maneuver, the right wing struck some other trees.
Investigation
The investigation focused on the pilot's visual assessment and the sequence of events leading to the collision. No causal determination was provided in the source material.