Tatra KT4


Tatra KT4 is the name of a four-axle type articulated tramcar developed by the Czech firm ČKD Tatra. The first pre-production vehicles entered service in Potsdam in 1975, with the first production vehicles in 1977. A total of 1,747 units were built, with initial deliveries to East Germany and later to the USSR and SFR Yugoslavia. KT4 variants were built for both standard gauge and metre gauge tramways. Production of the KT4 tramcar was halted in 1991 due to worldwide economic and political changes at the time. Production was briefly resumed in 1997 to construct the last 20 units for Belgrade, Serbia.
Since the start of the 1990s, many of the earliest production tramcars have gone through extensive refurbishment and rebuilding, including the replacement of folding doors and the installation of low-floor center sections.

History

The KT4 was originally designed to demands set out by the needs of the GDR, who found bogie cars too expensive and needed a solution to their aging fleet of two-axle vehicles. The first steps into the KT4s design were made when ČKD Tatra modified a six-axle K2 tramcar, to a four-axle suspended articulation formation which later presented itself in the KT4. The KT4 has identical pedal control systems and bogies to the Tatra T3 bogie tramcar. As production continued, the design was improved, noted particularly in 1983 with the addition of thyristor control type TV3. The type is called KT4t.

Variations

Variations of the KT4 exist, though they are generally subtle and focused around seat layout and pantograph type.
The KT4D model was delivered to the following GDR and North Korean cities:
CityDelivery yearsNumber delivered
Berlin1976–88574
Brandenburg1979–8316
Cottbus1978–9065
Erfurt1976–90156
Frankfurt 1987–9034
Gera1978–9060
Görlitz1987–9011
Gotha1981–826
Leipzig19768
Potsdam1974–8745
Chongjin199150
Plauen1976–8845
Zwickau1987–8822
TOTAL1974–901,042

In 1984, Leipzig handed over their eight trams to Berlin. Since the early 2000s, the Tatra tramcars in the former GDR are being replaced and sold to other countries in Central and Eastern Europe.

Original KT4D

Modernised KT4D

Sold KT4Ds

KT4SU

The Soviet Union ordered the KT4SU for their meter-gauge tramways, the following cities received deliveries:
CityDelivery yearsNumber delivered
Yevpatoria1987–9018
Kaliningrad1987–9030
Liepāja1983–8822
Lviv1976–88145
Pyatigorsk1988–9025
Zhytomyr1981–8820
Tallinn1980–8874
Vinnytsia1980–9081
TOTAL1976–90415

KT4YU

The KT4YU is the Yugoslav variant of the tramcar, which were delivered to the now Serbian and Croatian capitals. The last KT4s ever produced were delivered to Belgrade in 1997. Those tramcars were equipped with IGBT modules and recuperative braking and named KT4M-YUB. In 2002, 30 Belgrade tramcars were modernized in Goša FOM / Inekon, and marked as KT4-YUBM.
CityDelivery yearsNumber delivered
Belgrade1980–97220
Zagreb1985–8651
TOTAL1980–97271

Other variations of the KT4

A series of KT4 trams were also produced for Pyongyang, North Korea, but have subsequently had their articulation removed.