On December 14, 2000, about 1400 Alaska standard time, a wheel-equipped Cessna 180 airplane, N4955A, sustained substantial damage after colliding with a fence and trees at the Birchwood Airport, Chugiak, Alaska. The airplane was being operated as a visual flight rules (VFR), local personal flight, when the accident occurred. The airplane was operated by the pilot. The commercial certificated pilot, the sole occupant, was not injured. Visual meteorological conditions prevailed. During a telephone conversation with the National Transportation Safety Board (NTSB) investigator-in-charge (IIC), on December 15, 2000, the pilot reported he had just gotten the airplane from a maintenance facility at the Birchwood airport, and he was planning to fly to the Elmendorf Air Force Base, Anchorage, Alaska. The pilot said he performed an engine run-up to 1,700 rpm before takeoff. The run-up was normal. He then departed on runway 19R and began a left turn-out. Just after lift-off, the pilot said the engine did not seem to be producing full power. He did not recall the amount of power, but the airplane would not continue to climb above about 300 feet. He decided to return to the airport and began a landing approach to runway 19R. When the pilot pulled the throttle control to idle, the engine power did not change. It continued to run at less than full throttle, but he could not make any power changes, up or down. The pilot said he descended to the runway, but since he could not reduce power, continued to fly down the length of the runway until reaching the end. He said he was flying at low level, and did not remember to shut-off the engine with the mixture or magnetos. Upon reaching the end of the runway, he banked the airplane to the left along a taxiway. The taxiway abruptly ended at a six feet high fence. The airplane collided with the fence, and then struck numerous trees beyond the fence. The airplane received damage to the engine, wings, and fuselage. During a telephone interview with the maintenance facility personnel and the NTSB IIC, the mechanic/owner of the facility reported that the airplane's engine was removed and disassembled due a previous propeller strike. The engine was reinstalled, and had several engine runs to check for leaks and proper rigging of the engine controls. The mechanic, and another mechanic employee, observed the pilot perform an engine run-up before departing. The airplane appeared to only climb to about 500 feet and then return for landing. During the landing, the airplane touched down on the runway for about 5 to 7 seconds on the main landing gear tires. The touchdown point appeared to be about mid-length of the runway. The airplane then lifted off to about 40 feet until reaching the end of the runway. It banked hard to the left, bounced the main wheels on the taxiway, and disappeared from view. After the accident, the maintenance facility personnel recovered the airplane. During a postaccident examination of the engine, the nut that clamps the throttle linkage to the carburetor throttle arm, was found to be loose.