Grob G109 power loss during take-off at Moreton-in-Marsh leads to ditch impact
On April 6, 1986, a Grob G109 self-launching motor glider experienced a power loss during take-off at Moreton-in-Marsh, Gloucestershire. The aircraft was on a training flight and had landed earlier due to a storm. As it attempted to take off from the wet grass airstrip, the engine's power suddenly reduced, causing the glider to sink back onto the runway. The pilot attempted to clear a ditch at the runway's end but the right wing dropped, resulting in the undercarriage collapsing upon impact. Both occupants were unharmed, but the aircraft sustained significant damage. The cause of the power loss was not determined, though carburettor icing was suspected.
- Self-launch takeoff roll: During a self-launch takeoff from the 500-yard wet grass strip, the Grob G109 accelerated normally and became airborne at about 45 kt, well before the predetermined abandon point.
- Sudden power loss: While the aircraft was held level to build speed to the 52 kt climb-out value, the engine speed suddenly reduced, causing a significant loss of power.
- Attempt to clear ditch: With insufficient runway remaining to stop and seeing a wide ditch at the end of the strip, the pilot attempted to fly across it using the limited remaining engine power.
- Wing drop and impact: As the aircraft just became airborne again, the right wing began to drop and the right undercarriage struck the far side of the ditch, collapsing the fixed gear.
- Crash - no injury: The aircraft sank to the ground, slewed to the right, and came to rest in the field with substantial structural damage but no injuries to the two occupants.