The aircraft suffered a hydraulic system problem shortly before commencing an approach to Blackpool Airport. The hydraulic pressure fluctuated initially and there was subsequently a total hydraulic system failure, which was not recognised by the crew. The loss of hydraulic pressure resulted in the speedbrake/lift dump system and power brakes being unavailable, but the emergency braking system remained operational.
The emergency brakes, although available, were not applied during the landing and the aircraft overran the runway at about 80 kt and was extensively damaged. The occupants, who were uninjured, evacuated without assistance.
The investigation determined that, irrespective of the omission to apply the emergency brakes, the Landing Distance Available (LDA) at Blackpool was insufficient for the aircraft to land with a hydraulic failure. A fatigue crack in the port cap of the left hydraulic pump had caused a hydraulic leak which eventually resulted in the total loss of the hydraulic system.