According to a witness on the ground, the pilot-in-command landed from west to east and after unloading the supplies decided to takeoff in the same direction. The pilot taxied down to the end of the runway and upon turning around the witness stated the tail of the airplane came off the ground during the turn. The witness further stated that the end of the runway was marked with a tarp that was held down with rocks placed upon its corners. As the airplane started its takeoff roll, the witness noticed the tarp wrapped around the right section of the tail of the airplane. The witness ran out to the runway waving his arms but the pilot did not see him. The airplane lifted off at the end of the runway and did not gain any altitude. The right wing struck a tree and it cartwheeled into the ground. The airplane was on fire before the witness reached the accident site.