some shots of my dad's and my model railroad...
(1) Red switching/road switching diesel. 500 hp, being powered by a marine diesel with diesel-hydraulic transmission, this loco had a top speed of 60 kph and was mostly used for wayfreights, local passenger services on branchlines and light switching duties. Normally these locos wore a dark green or black livery. The red ones were rare, being used for switching passenger cars at bigger stations.
The marine diesel was of the same type being used for the German U-Boats... (the real things not what runs on the rails!