In order to obtain a more powerful express locomotive than those with the 4-6-0 wheel arrangement, the Reichseisenbahnen in Alsace-Lorraine had some of the first Pacifics built in Europe in 1908. However, in order to be able to use existing turntables and at the same time allow a large tender, the trailing axle had a very small distance from the third driving axle. 

This meant that the Belpaire firebox had to be moved between the driving wheels, so the G 12 was not one of the typical Pacifics with a wide firebox. Typical of French-influenced areas, they had four cylinders based on the de Glehn system. Other features included serve tubes in the boiler and an exhaust system with a variable cross-section and cloverleaf shape.

Since the boiler and firebox were too small compared to other Pacifics and ten-wheelers, only eight S 12 were built. The seven that remained after the First World War came to SNCF in 1938 as 1-231 A. After the Second World War, three came to Luxembourg, two to the GDR and two to Poland. While they were used in Luxembourg until 1950 and in the GDR until 1953, the two in Poland were decommissioned in 1946 without actually being used.

The closely linked Atlanta & West Point and the Western Railway of Alabama had to pull the Southern Railway's "Crescent" between Atlanta, Georgia and Montgomery, Alabama. So they each ordered one locomotive, which was given the numbers 290 (AWP) and 190 (WRA). Like the Southern Ps-4, they were based on the USRA Heavy Pacific, but like them also had smaller drivers. The diameter was initially 73 inches and was later increased to 74 inches with thicker tires, which explains the designation P-74.

Both machines were operated together. While one hauled the northbound Crescent, the other simultaneously took over the southbound one. They were retired in 1954, after which the 190 was scrapped. The 290 was saved by the “290 club”, but remained non-operational for the time being. It was finally refurbished between 1986 and 1989 and was used until 1992, when maintenance work on the running gear was required. It now resides at the Southeastern Railway Museum in Duluth, Georgia, awaiting visual restoration.

The Atlantic Coast Line was one of the few US railroads which used Pacific locomotives for dual service. The P-5-B was the successor of the P-5-A that had been of the USRA Light Pacific design. The P-5-B had a driver diameter of only 69 instead of 73 inches to be used in freight service. In the case of the ACL these were often light and fast trains with agricultural products.

The weight on the drivers could be changed by pins which in turn increased or decreased the weight on the leading truck and trailing axle. This changed the maximum axle load by nearly 4,000 pounds. The newer batches also had a booster. Of 165 locomotives built, the first 70 had Baker valve gear and the rest had Walschaerts. They were retired between 1950 and 1953.

The IV f was an express locomotive with which the Munich company Maffei had won a competition held by the Grand Duchy of Baden State Railways in 1905. After three pre-production models built by Maffei, 32 more followed from the Karlsruhe mechanical engineering company. It was the first locomotive in Germany with the 4-6-2 wheel arrangement, which is also known internationally under the American designation “Pacific”. The well-known Bavarian S 3/6 was later to become a development of the IV f.

The Pacific design and the bar frame instead of a plate frame were approaches that had been taken over from American locomotive construction. Nevertheless, the entire locomotive received a filigree and streamlined appearance, which was in contrast to the bulky American locomotives. In addition, the four-cylinder compound engine based on the Von Borries design was a typical feature of southern German express train locomotives.

Since the IV f was also to be used in mountainous areas away from the main Rhenish route, its 1,800 mm diameter driving wheels were relatively small. As a result, a higher tractive force could be achieved on inclines than with larger wheels, but the entire running gear reached high rotational speeds on flat land at high speeds, which also led to increased wear and consumption. To enlarge the grate area, the firebox was pulled behind the driving wheels and widened so that it is clearly visible from the outside. It was only because of this change and the resulting increased overhang that the 4-6-0 wheel arrangement had to be abandoned and the trailing axle added. By balancing the load between the two rear axles, it was possible to increase the adhesive weight by around three tonnes on well-developed lines.

When they were taken over by the Reichsbahn in 1925, 22 of the 35 locomotives were still in use, which became the class 18². While the more numerous former S 3/6 remained in service for a long time despite the high-maintenance power plant, all members of the former IV f were retired by 1930.

The Grand Duchy of Baden State Railways used the IV f from 1907 on its 413 km long main line from Mannheim to Constance. However, this was unable to cope with long, fast routes with its driving wheels, which were only 1,800 mm large. Thus, in 1915, the IV h was ordered from Maffei in Munich, where the IV f and the S 3/6 had already been manufactured. Since only use on flat routes was planned, the IV h received driving wheels with a diameter of 2,100 mm. This negatively affected acceleration, but made it possible to maintain high speeds for a long time. The certification was only for 110 km/h, which was 10 km/h faster than its predecessor series. It was only in the thirties that it proved on test drives at speeds of up to 155 km/h that it ran very smoothly even at higher speeds. It was therefore equipped with more powerful brakes and approved for 140 km/h.

The locomotive was powered by a four-cylinder compound engine, which combined characteristics of the De Glehn and Von Borries types. The low-pressure cylinders drove the second coupled wheel set and had to be located on the outside due to their large diameter. While the outer high-pressure cylinders on the De Glehn type were pulled back to achieve shorter connecting rods, the outer cylinders were at the height of the smoke chamber. Thus, the high-pressure cylinders were on the inside and drove the first set of coupled wheels. Since they were also pulled very far forward, they could be clearly seen from the outside.

When they were taken over by the Reichsbahn, they became the class 18³. After about ten years of service on the Baden trunk line, the 20 built IV h were replaced by class 01 standard locomotives and relocated to other locations. Although they had a higher fuel consumption than the newer locomotives, it later turned out that they could almost keep up with the 01 and even surpassed the 03 in terms of power. After all, the power measurements were in a range from 1,950 to 2,200 hp. 

After the war, all 19 remaining examples went to the Bundesbahn and only road number 18 314 ended up being traded for an S 3/6 to the Reichsbahn, where it was fundamentally rebuilt. All others were initially retired because their Number was very small. However, three were subsequently reactivated and modernized for use as brake locomotives or for other trials. The 18 316 was preserved and was again in running condition between 1995 and 2002, but was parked again after damage.

In 1927, the B&O put a total of 20 examples of the P-7 class into service, which at the time were the most powerful Pacifics ever. The power was achieved with a driver diameter of 80 inches and cylinders measuring 27 by 28 inches. The firebox, with a combustion chamber and thermic syphons, reached an area of 394 square feet. The first locomotive was manufactured with a booster on the trailing axle, the others were only prepared for its later installation. They were given names after the first 20 Presidents of the United States, beginning with No. 5300 “President Washington”.

The P-7 hauled the most important express trains of the B&O. Over time, there was no standard rebuild of the class, but various different modifications. This resulted in the classes P-7a to P-7d, which differed primarily in the heating area and, among other things, had different superheaters. The P-7a and P-7d were also streamlined. Trains they hauled included the “Royal Blue” and the “Cincinnatian”. Their service ended in 1958 after the introduction of diesel locomotives in express service.

The Bavarian S 3/6, later designated as the class 18^4-5, was probably one of the best-known express steam locomotives in Germany. Developed by the Munich company Maffei, it was not only procured by the Royal Bavarian State Railways from 1908, but even the Deutsche Reichsbahn commissioned new series until 1931.

Although more than 150 km/h had already been achieved with the S 2/6 trial locomotive in 1906, the speed to be reached with the S 3/6 was reduced to 120 km/h, which was more suitable for everyday use. Their performance program stipulated that a train weighing 400 tonnes should reach at least 115 km/h on the level. The same train should still be pulled at 95 km/h at 0.5 percent and at 65 km/h at one percent.

The locomotive was based on the Baden IV f and was given a driving wheel diameter of 1,870 mm as a compromise. This enabled the S 3/6 to cover long distances at a high line speed without excessive wear on the engine, without having to sacrifice too much traction for climbing. As with previous Bavarian express train locomotives, the running gear was built on a bar frame. 

Of the 159 locomotives of series a to o, only 18 locomotives of series d and e were built with wheel diameter of 2,000 mm in order to be able to drive at a constant speed of 120 km/h on flat lines between the largest cities in Bavaria. These were mainly the Munich-Nuremberg and Munich-Augsburg routes, on which there were hardly any significant inclines. They were soon given the nickname “Hochhaxige” (“the high-heeled one”) to distinguish them from the rest of the S 3/6.

Traction was provided by a four-cylinder compound engine, which enabled very smooth running and led to consumption that did not need to fear comparison with the later two-cylinder standard locomotives. Despite the significantly higher maintenance effort due to the internal cylinders, the S 3/6 continued to be procured in several series even after the Deutsche Reichsbahn was founded. This can be explained, among other things, by the fact that the new standard express train locomotive of the class 01 had an axle load of 20 tonnes and many main lines were not strengthened accordingly at the time. With an axle load of 18 tonnes, the last S 3/6 could also be used on almost all main routes until a lighter standard express locomotive became available with the class 03.

After the Second World War, all locomotives came to the Bundesbahn, where they were extensively modernized. Despite their still comparatively very good performance and economy, however, all of them were retired between 1961 and 1965, since a miscalculation during the rebuilding process had meanwhile made it necessary to reduce the boiler pressure and thus the power.

A few years before the First World War, Jean-Baptiste Flamme developed a very powerful boiler that was to be installed in a freight locomotive and an express locomotive at the same time. So from 1909 the type 36 with the 2-10-0 wheel arrangement and from 1910 the type 10 Pacific were built. Since the boiler was relatively short with a large diameter and the chassis of the Pacific naturally had a long overall wheelbase, the appearance of the Locomotive somewhat unusual with a long overhang in front of the smoke box.

The boiler had a grate area of five square meters and narrowed in front of the firebox. It delivered 2,250 hp, making the type 10 one of the most powerful Pacific locomotives in Europe. Since the bogie hardly had to carry any weight from the smoke box, the load was kept within limits despite the four cylinders with simple steam expansion. Due to the special arrangement of the cylinders, the inner cylinders were accessible from above, which made maintenance easier. Although the cylinders were in one plane, the inner ones drove the first driving axle and the outer ones the second. The problem, however, was the weight of the large firebox, which made the load of the trailing axle too high. The Type 36 didn't have this problem as the weight was carried by the coupled axles. 

As a result, the second batch from 1912 was delivered with a smaller grate surface in order to reduce the axle load on the trailing axle. However, this reduced the power to 1,950 hp, while the service weight of the locomotives was reduced by around four tons. A total of 58 pieces were made by 1914, when production was stopped due to the war.

In the 1920s, the locomotives received double chimneys and new feed pumps. From 1931 there was a major conversion with new feedwater heaters, a larger superheater, new safety valves and smoke deflectors. The result was an output of 2,700 hp for the first batch and 2,400 hp for the second batch. 1938 followed the installation of Kylchap blast pipes. A large proportion of the engines were retired in 1956 and some continued to run on a different route for three more years.

The last ten Pacifics that the Boston & Maine purchased were also the last Pacifics that Lima manufactured. Their task was regional traffic over distances of up to around 200 miles, and they were designed for an average speed of 70 mph or 113 km/h. The firebox contained three thermic syphons and arch tubes. The coffin feed water heater was concealed in the smokebox. Initially there was a skyline casing on the top of the boiler, which was later removed. The locomotives from the two production years 1934 and 1937 were designated P-4a and P-4b. They were given names that were chosen in a competition among kindergarten children and students. Only 3713, which is currently being overhauled in Steamtown, has been preserved.

The Boston & Maine's first Pacifics were 82 members of the classes P-1 and P-2. They were characterized by 73 inch (1,854 mm) drivers and cylinders which were sized 22 by 28 inches. The P-1 consisted of twelve saturated locomotives built in 1910 by ALCO. Between 1911 and 1916, ALCO delivered 70 P-2 which were superheated and had a much larger firebox. 

In 1915, also all P-1 were superheated at the cost of much of the tube heating surface. Later additions added to many P-1 and P-2 included an Elesco or Worthington feed water heater. All in all, they were referred to as unexceptional locomotives which did their work without many problems, but also without noteworthy records. With a factor of adhesion of 4.5 for the P-1 and 5.0 for the P-2, it doesn't look like slipping was an issue.