FTW99LA059

During a precautionary landing following a loss of electrical power, the pilot turned the airplane to avoid colliding with a pickup truck, and the airplane impacted trees. The pilot reported that while IMC, at 14,000 feet msl, he started preparing for ice penetration and turned on the two propeller anti-ice switches. The right propeller anti-icing circuit breaker popped, and when the circuit breaker was reset, the airplane experienced a total electrical failure. The pilot initiated an emergency descent, and entered into VFR conditions at about 1,500 feet. After about 30 minutes of trying to locate an airport, with it getting dark and thunderstorms in the area, the pilot elected to land on a narrow road with trees on both sides. Testing of the alternator system revealed discrepancies with the left alternator, both voltage regulators, and the right alternator out sensor.

On January 1, 1999, at 1705 central standard time, a Cessna 421C twin-engine airplane, N234CG, was substantially damaged during a precautionary landing near Shelbyville, Texas. The airline transport pilot was not injured and his four passengers sustained minor injuries. The airplane was registered to and operated by Metro Redevelopment, Inc. of Omaha, Nebraska. Visual meteorological conditions (VMC) prevailed, and an IFR flight plan was filed for the 14 Code of Federal Regulations Part 91 personal cross-country flight. The flight originated from the Lakefront Airport, New Orleans, Louisiana, at 1520, with a destination of Omaha, Nebraska.

The pilot reported that while in instrument meteorological conditions, at 14,000 feet msl, he advised Houston Center that "I may have to go up soon, to avoid ice as my thermometer had dropped [to] 6 degrees below zero, and I needed to make it go to below 10 degrees Centigrade BELOW Zero to avoid ice." After about a minute, he started preparing for ice penetration and "flipped" the two propeller anti-ice switches. Turning on the second switch popped the right propeller anti-icing circuit breaker. When he reset the circuit breaker, the airplane experienced a total electrical failure. He then initiated an emergency descent and entered into VMC at about 1,500 feet. The pilot further reported that he flew around about 30 minutes trying to locate an airport; however, with it getting dark and thunderstorms in the area, he elected to land on a road. The pilot stated that he made a few "S" turns to observe traffic, and during the approach to the road, the aircraft "hit several power lines and cables and flew under another double set." During the landing on the narrow road, with trees on both sides, he turned the airplane left to avoid colliding with a pickup truck, and the airplane impacted trees.

Examination of the aircraft by the FAA inspector revealed that both wings were damaged. The right main landing gear, nose landing gear, and 5 feet of the nose area forward of the bulkhead was separated from the aircraft.

On January 22, 1999, the alternator system was tested under the supervision of an FAA inspector. Testing of the alternators revealed that the left alternator was "bad"; however, there was 12 volts at the AUX terminal. The right alternator checked out "okay." "Both the left and right regulators tested bad and they would not regulate the voltage." The alternator out sensors were then tested. "The left sensor checked okay, and the right sensor checked bad." According to the FAA inspector, "the right sensor had an open circuit and would not have turned on the light on the annunciator panel. The left sensor would not have turned on the light on the annunciator panel because the alternator was producing voltage at the AUX terminal, and that would have kept the circuit open on the sensor."