The Erprobungsstelle 61 (Est61, later renamed Wehrtechnische Dienststelle für Luftfahrzeuge und Luftfahrtgerät der Bundeswehr, WTD 61) is the German unit responsible for test, evaluation and certification. As such, many of the German military aircraft types fly or have been operated by the unit. This F-104 ended up as a monument at its home base Manching.