The aircraft departed Dublin at 16:05 for the 4th leg of a rotation between Sligo and Dublin. The en-route segment of this flight was uneventful. At 16:50 , the aircraft was handed over from Shannon Control to Sligo Tower, descending to 3,500 ft to the SLG beacon for an NDB/DME approach to runway 11 (a 1199 x 30 m asphalt runway). At 16:53, the aircraft called overhead the SLG beacon and was cleared for the approach. Seven minutes later the flight reported at the Final Approach Fix and was cleared to land by the Tower, giving a wind of 120 degrees 15 kt, gusting 29 kts. Just prior to landing, the crew were given a wind check of 120 degrees 15 kt, gusting 31 kt. At 17:02 the aircraft made an initial touchdown at approximately the mid-point of the runway. The aircraft continued down the runway until it departed the paved surface at the right hand side of the threshold of runway 29. The aircraft continued on through a prepared run-off area at the end of the runway, for a further 50 metres, before coming to rest with the main wheels embedded in boulders that formed part of an embankment leading down to the sea. The main wheels were approximately one metre short of where the boulders fall away into the sea. The nose wheel, cockpit and forward section of the fuselage cleared the top of the boulder embankment and the aircraft tilted approximately 15-20 degrees nose down onto the outgoing tide. PRIMARY CAUSE: “The probable cause of this accident was a fast, low approach, leading to the aircraft landing late, beyond the normal touch down point, thereby making it impossible to stop the aircraft on the remaining runway available.” CONTRIBUTORY CAUSE: 1. The lack of an adequate overrun area before an aircraft, failing to stop on the runway, enters the sea. 2. The lack of experience of the Operator in scheduled air operations. 3. The changing operational management structure and uncertain nature of the direction of the company with regard to aircraft type and network development.