What happened
On 29 November 2002, a Ryanair Boeing 737-200 ADV, registration EI-COA, landed at Charleroi Airport in Belgium following a scheduled flight from Dublin. The landing was performed by the First Officer on a wet runway under light drizzle. After touchdown, the aircraft decelerated normally using reverse thrust and speed brakes, but the Captain took control of the aircraft at approximately 80 knots before reaching the S2 exit.
Seeking to avoid delaying a following aircraft on the ILS approach, the Captain decided to continue toward the end of the runway to vacate at exit S1. At approximately 70 knots, reverse thrust was cancelled. The Captain then attempted to use the brakes, but instead of applying steady pressure, the brakes were applied and released repeatedly. This modulation caused the anti-skid system to lose efficiency. Consequently, the aircraft failed to reach a safe taxi speed before reaching the S1 turnoff. As the aircraft attempted the turn, the nose wheel and part of the right main landing gear departed the paved surface and entered the soft grass.
The investigation
The investigation, conducted by the AAIU, examined flight data recorder (FDR) information and the aircraft's mechanical systems. Technical inspections of the braking and anti-skid systems revealed no mechanical defects, with all components found to be fully serviceable. The investigation also noted that the cockpit voice recorder (CVR) was not deactivated by the crew following the incident, which prevented investigators from accessing relevant cockpit communications.
Findings
- The aircraft was fully maintained and all mechanical systems, including the brakes and anti-skid unit, were functioning correctly.
- The runway surface was wet due to ongoing drizzle.
- The Captain elected to bypass the S2 exit to clear the runway quickly for following traffic.
- The use of an inappropriate braking technique, specifically the repeated modulation of the brake pedal, prevented the aircraft from achieving a safe taxi speed.
- The aircraft entered the turn at approximately 50 knots, which was too fast for the maneuver given the lack of deceleration.
Safety action
- The operator was advised to update its manual to instruct crews to de-activate the CVR after an incident.
- A recommendation was made for the operator to consider making autobrake selection mandatory for certain landing configurations.