Accident Overview
The pilot of a twin-engine airplane reported a loss of power in the right engine while overflying Tri-City Airport, Tennessee, at an altitude of 9,000 feet. The airplane was in clouds with an outside air temperature of approximately 0 degrees Celsius. The pilot applied right engine manifold heat for a few seconds, but observed no noticeable difference in engine performance. He also checked the right magnetos, noting no obvious malfunctions.
Descent and Approach
A descent for landing was initiated toward Tri-City Airport. During the descent, the pilot applied and removed manifold heat several times, with no appreciable effect. On short final approach, when the landing gear was extended, the right main gear did not indicate a down-and-locked position. There was insufficient time to perform the emergency gear extension procedure.
Go-Around and Landing
The pilot initiated a go-around, during which he discovered that the left manifold heat control was stuck in the 'ON' position. With less than full power available on the left engine and the right propeller unfeathered, the airplane could climb to only about 200 feet. The pilot continued flying until terrain clearance was no longer possible, then landed in a field with the landing gear retracted. The airplane slid into trees and was substantially damaged.
Findings
The official probable cause was the pilot's improper use of carburetor heat, which resulted in a continuing loss of engine power, and the right landing gear's failure to extend during a single-engine approach. A contributing factor was the insufficient time available to extend the landing gear via the emergency extension procedure.