Never heard about him advising the Spanish Army, and I think it is not correct. If he was indeed an adviser, I think he would have advised the Spanish Olympic equestrian team, not the Spanish Army cavalry branch. After all, his Spanish decoration, the "Gran Cruz de la Orden del Mérito Militar", was apparently awarded "for his services to the German-Spanish equestrian friendship":Edward L. Hsiao wrote:I remember reading about German general Horst Niemack going to Spain after World War II. He and some other Germans were advisers to the Spanish horse calvary army. Niemack was awarded a high Spanish neck decoration for his service to the Spanish Army. I forgot what source it was.
Source: http://www.lexikon-der-wehrmacht.de/Per ... ackH-R.htmIm Jahre 1953 erhielt er für seine Verdienste für die deutsch-spanische Reiterfreundschaft von Generalissimus Franco das Großkreuz des spanischen Militärverdienstordens. Ab 1954 war er Präsident der Ordensgemeinschaft der Ritterkreuzträger.
Anyway, I'm fairly sure he was never considered a member of the Spanish Army.
The first Spanish-made jet trainer was the HA–200 "Saeta", designed by a team headed by Willy Messerschmitt. I don't know if there were German test pilots involved in the development of the plane (I do know that the first test flight was made by a Spanish pilot, Fernando de Juan Valiente), but if there were they well could be staff from the Hispano Aviación firm and not members of the Spanish Air Force. Anyway, again I must say that without any names all this is just gossip, no way to confirm or disprove it.Edward L. Hsiao wrote:]There were German test pilots who used to be in the Luftwaffe and flew Spanish air force planes including the first Spanish made jet trainer.