The Tiny Twins.
After the Second World War, the V 36 was practically the only mass-produced diesel locomotive available to the new DB and the East German DR. Around 120 of these units built from 1937 to 1944 were still in existence and the DB had another 30 locomotives built from the same designs. They were used in switching work and on transfer routes.
These locomotives produced 360 horsepower and could be upgraded to the medium power class for road operation with light passenger or freight trains. A simple form of M.U. operation back to back was included in the design of the V 36. Both cabs were accessible by means of crossover doors, and direct communication between them was possible. At that time two-man operation was the rule anyway with this locomotive class; in operation as pairs the workplaces were separated by the buffer beams. The mechanical connection of the throttles for both locomotives and control from one cab was possible in a limited way.
The novel by Erich Kästner in 1949 gave the double locomotive its nickname in German "Doppelte Lottchen" or "Double Lotte" (in English, an approximate equivalent is "Tiny Twins"). The option of m.u. operation was used again and again until finally the compact V 100 was available in sufficient quantities. Today, two museum locomotives sometimes meet to form a special attraction - the "Tiny Twins".