History of the Flight
On 2 May 2007, at 1230 UTC, a Cessna 152 (registration G-BWEV) was on a private flight from Shoreham Airport, Sussex, to Andrewsfield Airfield, Essex. The aircraft had departed from Andrewsfield earlier that day for a one-hour instructional flight, after which its fuel tanks were filled to a total of 80 litres. The pilot of the accident flight, a 60-year-old Private Pilot's Licence holder with 304 total hours (57 on type), did not fly that instructional flight but was aware of its duration.
Using commercially available software, the pilot planned the flight from Shoreham to Andrewsfield and a return. The calculated fuel burn for the leg from Shoreham to Andrewsfield was 19 litres. Prior to departing Andrewsfield, the pilot dipped the fuel tanks, measuring 30 litres in the left tank and 40 litres in the right, as he considered the aircraft's fuel gauges to be inaccurate. The weather was CAVOK with wind 070°/15 kt at 3,000 ft amsl. The flight to Shoreham lasted 55 minutes and was uneventful.
At Shoreham, the pilot dipped the tanks again, measuring 20 litres in the left and 30 litres in the right. Using an assumed fuel burn of 25 litres/hr, he estimated an endurance of 2 hours. He took off at 1135 hrs, cruising at 3,000 ft amsl, 90-95 kt, with a power setting of 2,200 rpm. At 1230 hrs, about 11 nm southeast of Andrewsfield, the pilot requested airfield information. Approximately three minutes later, the engine began to falter. He selected carburettor heat ON, mixture fully rich, and applied full throttle, but the engine continued to falter. The left fuel gauge flickered around empty; the right indicated approximately ¼ full (18 litres). Suspecting fuel starvation, the pilot decided to make a forced landing and informed Andrewsfield. Shortly afterwards, the engine stopped completely.
Forced Landing and Aftermath
The pilot's initial choice of field was not achievable, so he selected a closer but smaller field. The aircraft touched down at about 60 kt with no flaps selected. Realizing he could not stop before the boundary hedge, he steered through a gap into the adjacent field. The aircraft eventually stopped in a hedge on the far side of that field. Before shutting down, the pilot transmitted to an airborne aircraft that he was uninjured and was vacating the aircraft.
Andrewsfield Airfield manager and an engineer from the maintenance organization attended the site. On inspection, they found no fuel in the right tank and 10 litres in the left tank.
Fuel Planning Discussion
G-BWEV was fitted with long-range fuel tanks, capacity 147 litres (5.5 litres unusable). The pilot's information manual for the Cessna 152 states that 3 litres is used during start-up, taxi, and takeoff (SUTTO), and at 2,200 rpm and 3,000 ft, fuel burn is about 19 litres/hr. The Chief Flying Instructor at Andrewsfield recommends 25 litres/hr based on 20 years of experience. Using 25 litres/hr and 3 litres for SUTTO, the estimated fuel remaining after the first instructional flight was 52 litres. After landing at Shoreham, the aircraft would have had about 29 litres (5.5 litres unusable), giving an endurance of approximately 50 minutes. The engine stopping after 55 minutes on the subsequent flight supports these calculations.
The pilot accepted that he ran out of fuel but could not understand how he measured the fuel quantity incorrectly on two occasions. He was also unaware that the aircraft had been initially filled to 80 litres that day; had he known, he might have been suspicious of his initial dipping before departing for Shoreham.