History of the Flight
The aircraft, a Cessna F172M registered G-BAOS, departed on a private cross-country flight from Hawarden, Cheshire, to Seething Aerodrome, Norfolk. Approaching Seething, the pilot descended and crossed overhead at 800 ft to assess wind direction and runway conditions. He then climbed to 1,100 ft and joined the circuit on a left base for Runway 24.
The approach was made with 20° of flap and carburettor heat selected to HOT. On final approach, the pilot selected 30° flap but realized he was high. After continuing the approach briefly, he initiated a go-around from about 200 ft above ground level (agl). He applied full power and selected carburettor heat COLD. During the go-around, recognizing a possible tailwind on the approach, he decided to reposition to a right base for Runway 06. As the aircraft climbed, he noticed a reduction in power; he lowered the nose to maintain airspeed and selected carburettor heat HOT. He also reduced flap from 20° to 10°, though later commented it may have gone to 0°.
Hoping the power would recover, the pilot opted not to commit to an immediate forced landing and turned left downwind, where several forced landing options remained. The power continued to decrease, and the pilot realized a landing was necessary. He had identified a field, but as he approached, his passenger alerted him to power lines ahead. He turned away, closed the throttle, and landed ahead in the field. The field contained a damp standing crop from recent rain. Upon touchdown on the main wheels, the aircraft decelerated rapidly, pitched forward, and came to rest inverted.
The pilot and passenger were disorientated after the accident but sustained minor injuries and evacuated through the side doors. The aircraft suffered substantial damage.
Weather Conditions
At the time of the accident, the weather at nearby Norwich Airport was reported as: surface wind from 330° at 14 kt, visibility greater than 10 km, few clouds at 1,400 ft, scattered clouds at 4,500 ft, temperature 8°C, dewpoint 6°C, and pressure 1018 hPa. There had been rain showers in the area. The conditions were conducive to carburettor icing.
Pilot Information
The pilot held a Private Pilot's Licence, was 42 years old, and had 431 total flying hours, with 7 hours on type. In the last 90 days, he had flown 13 hours, and 9 hours in the last 28 days.
Additional Information
The pilot reported suspecting carburettor icing as the cause of the power loss. He chose to continue flying rather than execute an immediate forced landing because some power remained and he expected carburettor heat to restore it. The Civil Aviation Authority Safety Regulation Group has noted that carburettor icing has been a contributory factor in numerous occurrences and continues to be studied.