What aircraft was involved and where did it happen?

The accident on null involved a aircraft, registration N-272, at IE.

What was the probable cause of the accident?

The runway excursion was caused by a destabilized approach resulting from the late selection of 50° flaps, combined with the failure of the ground spoilers to deploy due to throttle advancement, which prevented effective braking.

MD-11 Runway Excursion at Shannon Airport

A World Airways MD-11 overran the runway at Shannon Airport after a series of bounces and a failure of the ground spoilers to deploy.

What happened

On September 18, 1999, a World Airways MD-11, registration N-272 WA, was completing a scheduled passenger flight from New York JFK to Shannon Airport. While approaching Runway 24, the crew monitored challenging weather conditions, including recent wind gusts of 37 knots that had forced other heavy aircraft to divert.

During the final stages of the approach, the captain selected a 50° flap setting at approximately 300 feet altitude. The aircraft touched down 1,600 feet beyond the intended touchdown point. The landing was unstable, characterized by four distinct bounces. During the landing sequence, the throttles were advanced, which prevented the automatic ground spoilers from deploying. Because the spoilers failed to extend, the autobrake system also failed to activate.

Despite the pilot applying maximum manual braking and full reverse thrust, the aircraft could not decelerate sufficiently on the wet runway. The aircraft exited the end of the runway and traveled approximately 230 feet into the grass overrun area. There were no injuries to the 317 passengers or the 14 crew members on board.

The investigation

The AAIU examined flight data from the Digital Flight Data Recorder and Cockpit Voice Recorder, alongside meteorological reports and aircraft maintenance records. The investigation focused on the sequence of the landing roll, the configuration of the aircraft during approach, and the functionality of the braking and spoiler systems. Investigators analyzed the impact of the late flap configuration change and the subsequent failure of the automatic ground spoiler system (AGt) due to throttle inputs.

Findings

The late selection of 50° flaps destabilized the approach.
The aircraft touched down significantly past the normal touchdown zone.
The advancement of the throttles during the landing phase prevented the automatic deployment of the ground spoilers.
The failure of the spoilers to deploy meant the aircraft's weight was not properly transferred to the main wheels, severely reducing braking efficiency.
The autobrake system remained inactive because the ground spoilers did not deploy.
The crew did not call out the failure of the spoilers, which could have alerted the pilots to the loss of braking capability.