What happened
On 13 December 1999, a Gulfstream G-IV, registration VP-BIS, was conducting a training flight at Norwich Airport. The crew, consisting of a training captain and three trainee pilots, had arrived from Luton Airport to perform periodic training exercises. Following an initial successful landing on a wet runway, the crew changed positions and prepared for a second landing.
During the second approach, the crew initiated a missed approach procedure due to a lack of visual contact with the airfield. Upon deciding to attempt an ILS approach, the aircraft landed on Runway 27. While the pilot initially believed the runway condition remained consistent with the previous landing, the aircraft failed to decelerate as expected despite the use of full reverse thrust and wheel braking. The aircraft overran the paved surface near the centerline, coming to rest on firm grass approximately two metres beyond the runway edge. The nosewheel sank into the soft ground upon exiting the pavement. There were no injuries to the four crew members and no damage to the aircraft.
The investigation
The investigation examined the aircraft's flight parameters, meteorological conditions, and runway inspection records. The commander noted that the aircraft had been slightly high and fast on the final approach, with a light touchdown occurring outside the normal touchdown zone. The pilot also reported a lack of the typical anti-skid 'juddering' during braking, suggesting potential aquaplaning.
Meteorological reports indicated that snow had been falling since approximately 15:30 hrs. While an earlier runway inspection at 16:00 hrs had found the surface to be merely wet, subsequent observations by the pilot revealed a significant depth of slush on the runway following the incident. The investigation also reviewed the communications between Air Traffic Control and the flight crew regarding the state of the runway.
Findings
- The aircraft's approach was characterized by an excessive speed and a high descent rate, resulting in a touchdown point beyond the standard zone.
- Accumulated slush or snow deposits likely formed on the runway surface between the time of the initial inspection and the aircraft's landing.
- The reduction in braking effectiveness was exacerbated by the combination of the contaminated runway surface and the landing energy.
- The Aerodrome Controller did not provide a specific warning to the crew regarding the deteriorating runway conditions or the need for a new inspection.