Swiss Federal Railways C 5/6
For use in front of freight and express trains on the Gotthard, the SBB ordered the C 5/6, which was similar to the C 4/5 with a fifth coupled axle. Initially, three locomotives were built with four compound-acting cylinders and two with four simple-acting cylinders. The remaining 25 were built as compounds. Because of their power, they quickly earned the nickname “Elephant”. The 2901 and 2902 were also rebuilt into compound locomotives in 1920 and 1922, but did not achieve the same power as the others and were retired in 1933.
Since the Gotthard was electrified in the 1920s, the C 5/6 were relocated to the flatlands, where they were also used for heavy shunting duties. Since the Reichsbahn did not have enough locomotives for deliveries to Switzerland during the Second World War, 16 C 5/6s were leased to them. After the war, some were leased to France for the same reason. Their retirements took place between 1954 and 1968. Today there are two operational C 5/6 preserved and two more that are not operational.
Technical data
General
| Property | production | 2901-2902 |
|---|---|---|
| Built | 1913-1917 | 1913 |
| Manufacturers | SLM | |
| Wheel arrangement | 2-10-0 (Decapod) | |
| Gauge | 1,435 mm (Standard gauge) | |
Dimensions and weights
| Property | production | 2901-2902 |
|---|---|---|
| Length | 19.20 m | |
| Wheelbase | 8.80 m | |
| Service mass | 85.8 t | 85.3 t |
| Adhesion mass | 76.1 t | 75.6 t |
| Total mass | 127.6 t | 127.1 t |
| Rigid wheelbase | 6.45 m | |
| Water capacity | 18,000 l | |
| Fuel capacity | 7 t (coal) | |
Boiler
| Property | production | 2901-2902 |
|---|---|---|
| Grate area | 3.7 m² | |
| Firebox surface | 13.7 m² | |
| Tube heating surface | 197.65 m² | 207.5 m² |
| Evaporative heating surface | 211.35 m² | 221.2 m² |
| Superheater surface | 54.45 m² | 57.5 m² |
| Total heating surface | 265.8 m² | 278.7 m² |
Power plant
| Property | production | 2901-2902 |
|---|---|---|
| Driver diameter | 1,330 mm | |
| Boiler pressure | 15.5 bar | 13 bar |
| Expansion type | compound | simple expansion |
| Cylinders | four, HP: 470 x 640 mm and LP: 710 x 640 mm | four, 470 x 640 mm |
Power
| Property | production | 2901-2902 |
|---|---|---|
| Power source | steam | |
| Indicated power | 1,190 kW (1,618 PS) | |
| Top speed | 65 km/h | |
| Starting effort | 194.8 kN | 234.9 kN |
| Starting effort simple | 233.7 kN | |
| Estimated power | 1,050 kW (1,428 PS) | |
Calculated values
| Property | production | 2901-2902 |
|---|---|---|
| Factor of adhesion | 1 : 3.83 | 1 : 3.16 |
| Optimal speed | 37 km/h | 27 km/h |
| Power-to-weight ratio | 13.9 kW/t | 12.3 kW/t |
| Heating Surface Equivalent | 388.8 m² | 404.7 m² |
| Cylinder volume/HSE | 1 : 1,223.05 | 1 : 1,097.47 |
| Adhesive weight/Total | 1 : 1.13 | |
| Tractive force/Heating surface | 1 : 15.30 | 1 : 17.60 |
| Grate area/Heating surface | 1 : 71.84 | 1 : 75.32 |
| Firebox/Tube surface | 1 : 14.43 | 1 : 15.15 |
| Total/Superheater | 1 : 3.88 | 1 : 3.85 |