On January 13, 2001, about 1630 Eastern Standard Time, a Mooney M20C, N1398W, was substantially damaged when it impacted power transmission cables, then force-landed in the Taunton River, in Somerset, Massachusetts. The certificated private pilot was seriously injured. Visual meteorological conditions prevailed at the time of the accident. No flight plan had been filed for the local flight, which originated at Newport State Airport, Newport, Rhode Island. The personal flight was conducted under 14 CFR Part 91. According to a Federal Aviation Administration (FAA) inspector, the airplane was cruising northbound over the Taunton River, in an area that was urbanized on both sides. It passed over the Brada Bridge, then impacted one of two, eight-cable bundles of power transmission cables. The airplane continued northward, over the Brightman Street Bridge, then flew under another set of power cables, before being forced down in the river. After water touchdown, the airplane skidded into rocks along the river's western shoreline. In a later interview with the FAA inspector, the pilot stated that about 15 minutes after takeoff, he noticed that the engine was producing less power, and there was increased vibration. Just after passing the Brada Bridge and "just prior to reaching stall speed," the pilot applied carburetor heat. However, "owing to [a] reduced visibility at dusk, the approaching cable span was not observed in time.... After the cable strike, (approximately 10 seconds) the engine smartly picked up rpms, but by then, directional control of the aircraft was lost." On-scene examination revealed that one of the power cables in the southernmost bundle had been severed. The airplane's propeller had gouge marks on each of the two propeller blades, and both blade tips had been curled backwards. There was impact damage to both wings and the tail, and the cable impact "had clearly removed the rudder." Fuel samples were absent of water and debris, and the carburetor heat had been activated. The airplane's last annual inspection was completed on September 15, 1997. Weather, at airports approximately 15 nautical miles to the northeast and 12 nautical miles to the southwest, about 20 minutes after the accident, included clear skies, winds from the south at 4 to 5 knots, a temperature of 34 degrees Fahrenheit, and a dewpoint of 22 degrees Fahrenheit. Carburetor icing calculations indicated a probability of light icing during glide and while at cruise power settings. According to U.S. Naval Observatory data, sunset occurred at 1638.