KKS Class S

Class S
KKS Class S tram no. 208 in Karl Johans gate in 1900
Interior in 1960
Manufacturer	Schuckert & Co. Busch
Constructed	1899
Number built	20 motor cars 12 trailers
Capacity	20 seated, 14–20 standing
Operator(s)	Kristiania Kommunale Sporveie (1899–1905) Kristiania Sporveisselskab (1905–24) Oslo Sporveier (1924–67)
Specifications
Car length	7.8 m (25 ft 7 in)
Width	2.0 m (6 ft 7 in)
Weight	9.3 t (motor car) 6.4 t (trailer)
Traction system	2× Schuckert AB71
Power output	51 kW (68 hp)
Electric system(s)	600 V DC Overhead wire
Current collection method	Trolley pole / Bow collector / Pantograph
Track gauge	1,435 mm (4 ft 8 1⁄2 in)

Class S (Norwegian: type S) was a class of 20 twin-axle trams and 12 trailers built by Schuckert & Co. and Busch for Kristiania Kommunale Sporveie (KSS) in 1899. The trams were originally 7.8 meters (26 ft) long and 2.0 meters (6 ft 7 in) wide. They featured wooden benches in the longitudinal direction seating twenty. The motor cars had two motors providing a combined power output of 51 kilowatts (68 hp). The motor cars weighed 9.3 tonnes (9.2 long tons; 10.3 short tons), while the trailers weighed 6.4 tonnes (6.3 long tons; 7.1 short tons).

Ownership of the class moved to Kristiania Sporveisselskab (KSS) in 1904, when it bought KKS. The trams were variously rebuilt from 1918. One was converted to a snow plow, while three motor cars and three trailers were converted to cargo trams for hauling grain. The remaining units were rebuilt and lengthened in 1919 and 1920. The wheelbase was extended from 1.8 to 3.0 metres (5 ft 11 in to 9 ft 10 in) and the platform bays covered. A further rebuilding took place between 1921 and 1925, when they received new motors and undercarriages from Siemens Schuckertwerke. They passed on to Oslo Sporveier when it took over KSS in 1924. There the trams remained in service until 1967.

Kristiania Kommunale Sporveie was the third street tram operator in Oslo and the first to be owned by the municipality. The municipal council voted on 23 September 1897 to establish the company, which was issued the task of building three lines: Sagene Ring, the Rodeløkka Line and the Vippetangen Line. These lines opened in intervals in 1899 and 1900.

Two city engineers were sent on a study tour of Germany and the Netherlands to gain experience from tram operations there. KKS placed its order with Schuckert & Co. of Nürnburg and Busch, consisting of twenty motor cars and twelve trailers. All 32 units were delivered in 1899. Schuckert had recently delivered the first trams to Holmenkolbanen (HkB), which operated a suburban tramway in Oslo. However, KKS opted for larger trams than HkB, ordering trams of the same size as those operated by the two other street tram operators, Kristiania Sporveisselskab and Kristiania Elektriske Sporvei (KES). To avoid overlapping numbers with KSS and KES and KSS, the Class S motor units were numbered 201–220 and the trailers numbered 250–261. They received a dark red paint scheme and were KKS therefore became known as the "Red Trams".