Synopsis
An aircraft experienced a runway overrun during landing, subsequently impacting approach lights, after encountering heavy rain on final approach. The crew had been aware of thunderstorm activity in the area but ceased radar observation due to increasing workload and ground clutter.
Sequence of Events
Approximately 26 minutes before landing, the crew received SIGMET 1C, which advised of a line of thunderstorms extending from Milwaukee to St. Louis, moving southeast at 15 knots. They also became aware of a thunderstorm located west of the airport. While about 20 miles northeast of the airport, the crew could see the storm visually and on radar, positioned west of the field.
At approximately 15 miles from the airport, the crew stopped looking at the radar because of increasing workload and ground clutter interference. During the final approach, rain intensity increased. The aircraft landed, overran the runway, and struck approach lights.
The crew did not consult the landing field length chart in the company operations manual. That chart indicated a stopping distance of 7,930 feet from initial brake application for a 'very wet' runway.
Another flight that was arriving in the airport area at the time of the accident received vectors north of the airport and held for about 10 minutes. They then flew '...on the back side of the weather for an approach to runway 14R...'. Runway 27L, which was 10,141 feet long, was available.
Weather Conditions
While the source does not provide a formal weather characterization, it notes that the crew received a SIGMET for thunderstorms and observed a thunderstorm west of the airport. Rain increased in intensity during the final approach.
Operational Considerations
The crew did not reference the landing distance performance data for a wet runway. The available runway length for landing was 10,141 feet on Runway 27L, but the aircraft landed on a different runway (not specified in the source). The approach was conducted in increasing rain without continued radar monitoring.