Accident Overview
On September 14, 2017, about 1130 eastern daylight time, a Beech C23 (registration N2120W) operated by Maine Instrument Flight was substantially damaged during a forced landing after experiencing a total loss of engine power while on approach to Machias Valley Airport (MVM) in Machias, Maine. The private pilot, who was the sole occupant, was not injured. The flight was conducted under Title 14 Code of Federal Regulations Part 91 as an instructional flight. Visual meteorological conditions prevailed, and a visual flight rules flight plan was filed. The flight originated from Augusta State Airport (AUG) in Augusta, Maine, about 1015.
Flight Sequence
The pilot was accruing cross-country flight experience for his commercial pilot license. He and his flight instructor reviewed his flight planning for a three-leg cross-country trip, and he departed with full fuel. During the first leg, approximately 10 miles from MVM, the pilot descended the airplane to the airport traffic pattern altitude. While in the traffic pattern, as the airplane turned onto a left base leg for the runway, the engine began to run roughly. The pilot verified that the mixture was full rich and the fuel boost pump was on. He also applied carburetor heat, but about 15 to 20 seconds later, the engine lost all power.
Forced Landing
After the power loss, the pilot turned the airplane directly toward the runway, resulting in a 45-degree angle to the runway threshold. Realizing the airplane would not glide to the runway, he prepared to land in a grass area just before the runway. During the landing, the landing gear sank into soft ground, and the nosewheel touched down hard, collapsing the nose gear. The airplane spun 180 degrees and came to rest upright in the grass area.
Examination
A Federal Aviation Administration (FAA) inspector examined the airplane and found damage to the right wing spar. Twenty gallons of fuel per wing were removed from the airplane. The magnetos, fuel boost pump, and engine-driven fuel pump tested satisfactorily. The carburetor was intact, and its screens and fuel bowl were free of debris. The inspector rotated the propeller by hand and noted camshaft, crankshaft, and valve train continuity to the rear accessory section of the engine. Due to damage to the engine mounts and exhaust system, an engine test-run was not performed. The engine had accumulated approximately 359 hours since major overhaul.
Weather Conditions
The recorded weather at Hancock County-Bar Harbor Airport (BHB), located about 40 miles west of the accident site, at 1156 was: wind from 180 degrees at 5 knots, visibility 10 miles, sky clear, temperature 24°C, dew point 17°C, altimeter 29.83 inches of mercury. Review of an FAA Carburetor Icing Probability Chart for the given weather conditions indicated "Serious icing (glide power)." A descent checklist from the pilot operating handbook for the airplane model stated: "Carmuretor Heat - FULL ON or FULL OFF, AS REQUIRED."
Probable Cause
Not stated in the source.