What happened
On 30 September 2005, a Cessna 421C Golden Eagle, registration N421CA, was performing a private flight at Northrepps Airfield in Norfolk. The pilot initially attempted an approach to Runway 18 but decided to execute a go-around to reposition for a landing on Runway 36, intending to utilize the uphill slope of that runway to assist in braking.
The runway at Northrepps is a short grass strip measuring 1,617 ft with a 1.8% downslope on Runway 18. On the day of the accident, the grass surface was wet. During the approach to Runway 36, the pilot touched down near the threshold and immediately retracted the flaps. However, as the aircraft progressed along the runway, the pilot noted a significant loss of deceleration. The pilot described a sensation similar to aquaplaning, where braking authority appeared to vanish. Consequently, the aircraft failed to stop within the runway limits, crossed a grassed overshoot area, and struck an earth bank before coming to rest on a public road. There were no fatalities and no injuries to the pilot or the two passengers, though the aircraft sustained substantial damage to the engines, wings, fuselage, and landing gear.
The investigation
The AAIB investigation utilized field findings and video evidence recorded by a member of the public. The investigation examined the pilot's pre-flight preparations, specifically regarding wind information and performance calculations. While the pilot had consulted flight guides and contacted the airfield operator, the investigation found that the pilot did not consult the aircraft's flight manual to formally calculate landing distances for the specific conditions.
Analysis of available wind data, including reports from nearby airfields and the aircraft's onboard GPS, indicated that a significant tailwind component was present for the landing on Runway 36. The investigation also reviewed the impact of the wet grass surface and the runway slope on braking effectiveness.