Incident Overview
On 18 January 2000 at 1100 UTC, a Cessna T310R (registration G-GREN) was on approach to Llanbedr, Powys, after experiencing a dual engine failure. The aircraft, manufactured in 1978, was powered by two Continental Motors Corp TSIO-520-B piston engines. The flight, operated under a Private Pilot's Licence, originated from Southend Airport, Essex, with a destination of Weston Airfield, Ireland. The sole occupant, a 57-year-old pilot with 930 total flight hours (15 on type), was uninjured, and the aircraft sustained no damage.
Sequence of Events
While in level flight at Flight Level 80 and approaching the North Wales coast, the left engine stopped. The pilot, receiving a Flight Information Service from London, secured the engine and broadcast a MAYDAY call. He was instructed to squawk 7700 and switch to emergency frequency 121.5 MHz. During these actions, the right engine also stopped. The pilot sighted Llanbedr airfield on the coast and elected to make an emergency landing. Weather conditions were clear with surface wind less than 5 kt.
Llanbedr Air Traffic Control (ATC) observed the emergency squawk on radar and heard transmissions on 121.5 MHz. They contacted the Distress and Diversion centre, assumed control of the aircraft, and passed airfield details to the pilot. The pilot initiated a visual approach to Runway 36 but realised he would land short. He informed ATC of his intention to land in a field outside the airfield boundary, and the Aerodrome Fire Service was alerted. The aircraft landed in the field without damage or injury.
Investigation Findings
The pilot reported he had mismanaged the fuel system, allowing the auxiliary fuel tanks, from which the engines were feeding, to run dry. The main tanks contained sufficient fuel for the planned flight to Ireland. The pilot had approximately 350 hours of twin-engine flight experience but was not very familiar with the Cessna 310 type. The fuel system design on the Cessna 310 is such that auxiliary tanks are typically used during cruise, and excess fuel is returned to the main tanks. Consequently, the endurance of the auxiliary tanks may be less than their initial contents. Fuel gauges do not necessarily display the tank in use and require correct selection, which can cause confusion for pilots less experienced with the system.
The aircraft was recovered to the airfield and departed the following day. The CAA incident database recorded no similar previous events involving Cessna 310 aircraft in the UK, though numerous occurrences had been noted in the United States.