The Junkers F 13 was the world's first all-metal airliner; its impressive characteristic was a corrugated duralumin fuselage. Rebuilding of this "primordial mother" of passenger traffic began in 2009 based on historical construction plans and using the latest surveying technology. Crucial to the success of this prototype was the right mixture of high-precision manual work and the necessary know-how – one of the great strengths at Kaelin.
One very special assignment was the field repair of a Pilatus Porter PC-6 for an Indonesian airline. The plane had a landing accident at the Long Alango airfield. The problem was getting there, because the landing strip could only be reached by plane in a three-hour flight over the jungle without any opportunity to land.
