At the beginning of the 1890s, express trains were still transported on the Gotthard railway in two separate ways. In the lowlands from Lucerne to Erstfeld the trains were pulled by light tank locomotives and in the mountains freight locomotives took over. In order to accelerate these trains, new locomotives were needed that combined sufficient tractive power with a higher maximum speed, thus making locomotive changes and double heading superfluous. The requirements were to transport an express train of 140 tonnes alone on the mountain and 250 tonnes on the flat.

In order to enable sufficient tractive effort and, at the same time, good curve running, the locomotive was given three coupled axles and a leading bogie, which made it the first locomotive of this wheel arrangement in Switzerland. A driving wheel diameter of 1,610 mm represented a good compromise for the required performance. For smoother running, coil springs were used instead of leaf springs, which were later replaced with leaf springs.

The first prototype with the number 201 was built with a three-cylinder compound engine. In order to develop a higher tractive force on the mountain, the low-pressure cylinders could be operated permanently with live steam. In the 202, a four-cylinder compound engine according to De Glehn was used, which also worked with the compound effect on the mountain.

For the production of the 28 series machines, the arrangement with four cylinders was chosen because it ran more smoothly and was more economical on the mountain route. Compared to the 202, the cylinders were enlarged while the boiler pressure was increased from 14 to 15 bars. The high-pressure cylinders acted on the first and the low-pressure cylinders on the second coupled axle. A slightly smaller boiler was installed in the last six locomotives from number 225 onwards. These locomotives were later retrofitted with a superheater. 

The locomotives could pull a 320-tonne express train on the flat at 50 km/h. A load of 140 tonnes was initially planned for the ascent at 40 km/h, which was later reduced to 120 tonnes to reduce fuel consumption. Likewise, the tender was expanded from a water capacity of 14.4 to 17 cubic meters. When the Gotthard Railway was nationalized in 1909, the SBB gave the locomotives the numbers 901 to 930. After the line was electrified in 1920 and these locomotives were slower than later type A 3/5 locomotives, they were retired between 1923 and 1926.

After the first type A 3/5 express locomotives, the Gotthardbahn had Maffei develop another variant of this type in 1908. Although it was primarily intended for use on the company's valley routes, it was also intended to pull lighter trains on the mountain routes and, like its predecessors, was therefore given relatively small wheels with a diameter of 1,610 mm. Maffei used the basic construction of the Bavarian P 3/5 as a basis.

Thus, the locomotives had a bar frame and a long, narrow firebox that lay between the wheels of the second and third coupled axle. The roof of the firebox sloped backwards so that it was always sufficiently covered with water when driving downhill on the 2.7 percent mountain route. To increase efficiency, a Crawford-Clench design steam dryer was used, which was replaced by the Schmidt smoke tube superheater from 1913 onwards.

The dimensions of the cylinders and parts of the valve gear corresponded to the type C 4/5 freight locomotive also supplied by Maffei in 1906 in order to reduce the number of spare parts to be kept on hand. All cylinders acted on the first coupled axle according to the Von Borries design. A piston valve was used on each side, which simultaneously controlled one high- and one low-pressure cylinder. While this arrangement was efficient, over time it resulted in damage to the valve gear.

Sectional drawing with dimensions

Die Lokomotive, June 1909

Maffei delivered four vehicles, four more were delivered by SLM in Winterthur in the same year. On the valley lines, they could transport 350-tonne trains at one percent at 60 km/h, and at 2.7 percent on the mountain route, it was still 150 tonnes at 40 km/h. The Gotthard railway was nationalized as early as 1909, so that the locomotives were now operated by the SBB. After the Gotthard Railway was electrified, it was scrapped as early as 1925.

Schematic drawing of Nos. 89 to 92 from the SLM

SLM

When the 2-6-0 wheel arrangement was not yet widespread in Europe, the Gotthard Railway had eight tank locomotives with this wheel arrangement built in Esslingen. They were to be used to pull passenger and express trains on the mountain route and also to pull freight trains in the lowlands. Four more followed in 1883 from the SLM. These differed from the first eight by the coal bunker, which was behind the cab. Upon the nationalization in 1909, all came to the SBB. They were retired between 1914 and 1933.

The challenges for locomotives on the Gotthard railway were not only the incline of 2.7 percent, but also the spiral tunnels with a radius of 300 meters. This required a high tractive force and at the same time made the adhesion conditions more difficult. In order to be able to dispense with the previously necessary one or two auxiliary locomotives per train, eight-coupled locomotives or those with articulated chassis should be procured. In 1890 Maffei in Munich delivered locomotive number 151 to test the Mallet design.

The tank locomotive had six coupled axles and no carrying axles and was therefore given the type designation Ed 2x3/3. All cylinders acted on the respective third coupled axle. Due to the short distance between the wheels, only the first and last axle of each running gear group could be braked from the outside, otherwise there would have been no space for the brake pads between the wheels. Since enough space had to be planned for the water tanks on the sides of the boiler, the boiler turned out to be relatively small for a locomotive with a service weight of 87 tonnes.

Since a high steaming capacity was required for the long, continuous incline, the Ed 2x3/3 quickly reached its limits. Although the engine offered sufficient traction and was able to convert a lot of power, the boiler was too small in comparison. Calling up full power for a short time was also difficult because the maximum coupler force could be exceeded. Thus the maximum train weight of the Ed 2x3/3 on the Gotthard railway was only 200 tonnes, while the existing D 4/4 could pull 175 tonnes. The Mallet thus remained a one-off while further, reinforced batches of the D 4/4 were purchased.

Starting in 1898, the Swiss North Eastern Railway got 25 4-4-0 express locomotives from the SLM. They were called A 2/4 and were two-cylinder compounds. Being the only inside-cylinder locomotives of the NOB, their designers hoped to get smoother running characteristics. The Walschaerts valve gear was located on the outside.

On flat lines, they were usually used in trains of 300 to 600 tonnes and 200 to 240 tonnes on 1.2 percent. After the NOB became part of the SBB in 1902, the SBB ordered 25 more. The newer locomotives had a steam and a sand dome, while the earlier ones didn't have any domes. Only the three oldest were retired in 1917, all others followed in 1925.

These freight locomotives were built according to the Longboiler or “Bourbonnais” design, i.e. as a six-coupled with large overhangs both at the front and rear. A first series of 16 locomotives was built between 1891 and 1895 and a second of 24 locomotives from 1897 to 1902. The locomotives of the second series had compound engines and the last machines were delivered directly to the SBB. After the First World War, eight came to MÁV. The SBB parted with the last machines by the end of the 1920s.

The Nordostbahn grouped together a total of 32 two-axle tank locomotives under the name E 2/2. They were built between 1865 and 1876 and differed significantly in some respects. The first four locomotives were developed by machine master Krauss and built in the NOB's own workshops. A significantly heavier variant was also built four times under Maey. A ninth machine was created from the rebuild of a D 1/3, which was not officially designated as E 2/2. Finally, the SLM and the Maschinenfabrik Esslingen delivered a further 24 locomotives, which were again heavier and based on the C 2/2.

The E 2/2 was not only used in shunting service, but also on branch lines in passenger and freight service. The first four were scrapped in 1882. All others received a new boiler between 1884 and 1906. The machines that remained in 1916 were sold to the Army Administration of Austria-Hungary in 1906 and from there came to the FS and MÁV.

When the Rigi Railway opened on May 21, 1871, it was the first rack railway in Europe. It first led from Vitznau on Lake Lucerne at an altitude of 439 m (1,440 ft) to the Rigi Staffelhöhe at 1,550 m (5,085 ft). Only two years later, after negotiations with the canton of Schwyz, could the route be extended to Rigi Kulm at an altitude of 1,752 m (5,748 ft). On this line, which has a gradient of up to 25 percent, the Riggenbach system is used, in which a single gear wheel engages the central rack from above.

The first ten locomotives were delivered between 1870 and 1873 by the workshops of the Swiss Central Railway in Olten and SLM. The four examples of the SLM were the first locomotives ever to be manufactured by this company. All locomotives were characterized by the fact that all equipment was inclined by twelve percent in order to enable easy water management in the boiler and convenient operation on the sections with different steepness.

No. 9 in the original version with vertical boiler

Giorgio Sommer

In the beginning they had a vertical boiler, but this did not prove itself and was later exchanged for a horizontal one. The gear wheel was on the valley-side axle and was driven via a reduction gear. The cylinders were directly behind the axle on the mountain side. A centrifugal governor, which actuated the brake when the rotational speed was too high, protected the locomotive from excessively high speeds when going downhill. At the uphill end was an open baggage platform. One large or two small trailers could be taken along to transport people.

In 1899 and 1902, SLM delivered two heavier locomotives with horizontal boilers and a boiler pressure of twelve bars. These had a separate drive shaft, which was in the center of gravity of the locomotive and led to the relocation of the cylinders in front of the axle on the mountain side. They could now push a large and a small trailer at the same time.

Between 1911 and 1929 four of the locomotives were fitted with a superheater. The two older ones received a new boiler, larger cylinders and new piston valves. In the meantime number 14 appeared as H 1/2, which had come from the Arth-Rigi railway. Between 1913 and 1925 the three H 2/3 were put into service and the H 1/2 were soon used less often. With the electrification in 1937, all steam locomotives were retired. At this point, number 7 received the original vertical boiler again and has been operational again since 1996.