After 1945, the tram networks in most Polish cities relied on the small, slow and outdated Konstal N trams. The N-class trams were intended as a temporary measure to quickly improve the disastrous state of public transport in the aftermath of World War II, and were in fact based on a wartime German design, but all attempts at designing a better tram in Poland ended in failure. In 1955, two Tatra T1 trams were bought by the Warsaw Transport Authority. In 1956, these were sent to the Konstal works in Chorzów for analysis, and formed the basis for the first Konstal prototype called 11N. The prototype was then modernised: added were a different interior, Belgian ACECelectrical equipment, different wheels and transmission. In 1959, the prototype was put into production as the 13N.
Passenger service
Konstal 13N was a single-module unidirectional tram with three doors on the right side. It held 122 passengers, and was capable of reaching68 km/h. They were most often used in sets of two, though in peak times, and on particularly busy routes, sets of three were sometimes seen. Although early units suffered from reliability issues, these were soon rectified. The 13N remained in production for 10 years, and in that time, 842 units were built – 838 of those served in Warsaw, and the other four in the Upper Silesian network. The 13N went on to form the backbone of the Warsaw tram network for over 50 years. Due to their shape, they were nicknamed parówka and given stock numbers 1-500 and 503-840 . In the 21st century, with the need for more energy-efficient, easier-to-access low-floor trams, the 13N units were phased out and replaced by PESA 120Na. The last day of passenger service on a 13N was 31 December 2012.
Konstal 13N also forms the basis for the company's other trams seen in all Polish cities with tram networks. Konstal 102N and the subsequent 102Na are both articulated versions of the 13N, and the Konstal 105N started out as 13N in a more modern, lighter body.
Today
No 13N trams remain in regular passenger service after 2012, but several serve as museum cars in Warsaw, and Silesia. Due to their sturdiness a number of 13Ns have also been rebuilt as track maintenance vehicles.