ChS4 – the first comfortable AC passenger locomotive in the former USSR The ChS4 electric locomotive was developed by the Škoda Works (Czechoslovakia) in the 1960s for hauling passenger trains on AC-electrified railways. It was the first locomotive to combine high power with improved crew comfort – featuring a modern ergonomic cab, better heating, and sound insulation, making it a major step forward compared to earlier models. With a power output of 5100 kW and a top speed of up to 160 km/h, the ChS4 provided fast and reliable passenger service on major intercity routes. For decades, it was the primary locomotive for AC passenger transport in Ukraine, operating on key lines between Kyiv, Kharkiv, Lviv, Odesa, and other major cities. Technical specifications: Power system: AC, 25 kV, 50 Hz Top speed: 160 km/h Power output: 5100 kW Wheel arrangement: Co’Co’ Weight: approx. 120 tons Tractive effort: up to 260 kN Manufacturer: Škoda, Czechoslovakia The ChS4 became a symbol of a new era in railway transport and remains an iconic locomotive for generations of railway workers and passengers.