Mr B,
I took it from this - perhaps the translation is incorrect and it should be Sauerland ? One of the other articles I posted a link to had a local police spokesman quoting an investigation as well.
"Flugzeugabsturz im Sauerland:Staatsanwaltschaft ermittelt wegen fahrlässiger Tötung" [Plane crash in Saarland: Prosecutor investigating pilot for manslaughter] (in German). Der Spiegel. Retrieved 24 June 2014.