Wind turbine collapses at Haltern AV9 wind park in Germany

On 29 September 2021, a Nordex N149/4.0-4.5 wind turbine almost completely collapsed at the Haltern AV9 wind park in North Rhine-Westphalia, Germany. The turbine had been installed on a 164 metre hybrid tower in January 2021 and commissioned on 11 March 2021. No one was injured in the incident. Following the collapse, the site was secured and an interdisciplinary team of experts began a root-cause analysis, working with authorities and insurance companies. As a precaution, Nordex temporarily shut down all turbines of identical configuration, including 22 further units installed or being installed in Germany. Drone footage was used to assess the site before allowing safe access for detailed component analysis, including tower segments and rotor blades. Recovery of the turbine's bottom box was planned to allow analysis of operational data at the time of the incident. At the time of the statement, no cause had been identified and investigations were ongoing in all directions.

Not reported at the time of the statement; investigations were ongoing into all possible causes.

1. Following any structural failure of a turbine, operators should promptly and precautionarily shut down all units of identical configuration until the cause is understood.
2. Securing the incident site and using drone imagery before allowing personnel access supports safety during early investigation stages.
3. Recovery and analysis of turbine control and monitoring data (such as bottom box data) is important for establishing root cause and should be planned for early in the investigation.

nordex-online.com/en/2021/10/statement-on-the-collapse-of-a-wind-turbine-i...