KTM-1 — is a Soviet-made two-axle tram with a body made of solid metal, KTP-1 is a two-axle trailer car to intended to work under KTM-1 traction. It was the first Soviet-made tram to be originally single ended, as well as designated to work on looped (not dead-end) lines. Also, it was a first Soviet-made tram with wide four-segment folding doors and bigger passenger storage spaces. Doors were driven pneumatically.
KTM/KTP1 developments began right after the end of the World War two. These trams were intended for replacement of obsolete pre-war tram series. KTM/KTP1 was a kind of transitional stage between pre-war and post-war tram developments. In difference of the majority of pre-war trams, КТМ/КТП-1 featured solid metal body. Meanwhile, they were two-axle and intended to use only by motor-trailer scheme. Later on people refused to use two-axle trams, and all the trams were started to be equipped with bogies. And the articulated trams, as well as Multiple Unit Systems came in use, on segment with huge ridership.
Why archaic design features?
Despite old the old design, the KTM/KTP1 tram was not an engineering mistake. It was expected to use KTM/KTP1 it tram properties, where a service-base was moderately weak (the war detracted the modernization of technical equipment in tram properties), the use of more modern trams could be a problem for all of them. Some of the tram properties had worn tracks, which were incapable to be used by heavier trams. That time, two-axle trams could work on the lines with a moderate ridership.
The production of experimental KTM/KTP1 trams began in December 1947 on a Tram Manufacturing Plant in Ust' Katavsk City. IN the next year, the plant started the serial production of the trams. The production lasted till the year of 1961, when the plant switched to the production more modern КTM/КTP-2 trams.
KTM/KTP1 worked in numerous cities, that's why it is much easier to point the cities, where these trams did not exist. In Russian Federation these cities were Zlatoust, Kolomna, Kopejsk, Kursk, Leningrad, Noginsk, Smolensk, and Yekaterinburg.
KTM/KTP-1 trams started to be removed from passenger service by the middle of the 1970s. In Ukrainian cities of Zaparozh'e and Odessa, Ukraine, KTM/KTP1 were in service till 1986. Some of them were rebuilt into service trams.
The body of the tram is rigid (solid) and continuously welded of metal. The frame and the coating are the main carrying elements. Doors - single segment, from right side only (the tram was built as a one side). The tram was designed for a wide gauge tracks, as found in Russia (1,524 mm (5 ft)), however in Rostov-Na-Donu KTM/KTP-1 were rebuilt for European rail gauge (1,435 mm (4 ft 8 1⁄2 in)).
The motor tramcar was driven by fast DK-254А engines, with a power of 50 kW (67 hp) per each. Two step reductor was used as a power transmission from a traction motor to the leading wheel pair. In the rear wheel pair a two step reductor with a kardan of an automobile type was in use. The tram was driven using the fist-like controller МТ-22 or МТ-1. The tram collected electric power by a bugel', however in Rostov-na-Donu trolley poles were in use. The brakes, and doors were pneumatic. There was a special valve, which lead tram to full stop if a multiple unit was broken. The hand brake also existed.
Due to high use on some routes, three and four car tram couples were used. This was done since KTM/KTP1 trams were not intended to work as multiple traction systems. In these cases the motor circuits of two tramcars are combined into one, and everything was done as in 4-car units.
The low level of comfort is a major fault of the tram. The seats in trams were wooden. Since the car-base of the tram was not perfect, the tram squealed while making turns. Compressors also made much noise.
Due to external similarity sometimes it is possible to see an opinion about the similarity of КТМ-1 tram, and American-made PCC trolley. In reality, this similarity is only in external view. In difference of PCC trolleys, which had boogies, КТМ-1 was a double-axle tram. The control system of KTM-1 was different of PCC.