The P160 DE and F140 DE are two diesel locomotives from the TRAXX 2E generation. The designations are made up of “passenger - 160 km/h” (P160) or “freight - 140 km/h” (F140) and DE for “diesel-electric”. After no diesel variants could be sold with the TRAXX 1 and 2, the 2E with its modular design was more attractive in this respect. Since there is an installation area for a power converter or diesel motor with generator in the machine room, diesel-powered locomotives can be implemented with the same body, thus saving money. An MTU 16V 4000 engine was installed in this installation bay, which originally had an output of 2,200 kW. External differences to the electric locomotives are initially only additional ventilation grilles on the sides and a higher roof. While the F 140 DE freight version has node-suspended motors, the passenger version has quill drives for better driving characteristics at higher speeds.

The first order for the P160 DE went back to the Lower Saxony commuter company, which ordered eleven units in 2005. The engines, now referred to as the class 246 based on the class 146, were delivered in 2007 and are used, among other things, with the “Metronom” brand on the Hamburg-Cuxhaven route. The only example on the DB was road number 246 010, which belonged to the Southeast Bavarian Railway for less than a year in 2009. The F140 DE was first ordered by leasing company CBRail in 2006 and also delivered in 2007. It is listed in Germany as class 285. Other customers were the Polish Lotos Kolej and various private railways from Germany. The Pressnitztal railway uses the locomotives as towing locomotives for failed multiple units on the Erfurt-Leipzig/Halle high-speed line. At the request of the freight transport division of the SNCF, a more powerful variant with 2,400 kW was developed, which is used as the BB 76000 or BB 76100 in cross-border traffic.

The class 37, known as the English Electric Type 3 until TOPS numbering was introduced in 1968, is one of Britain's best-known diesel locos. Their use began in 1960 with the first production batch of 42 locomotives and the total had increased to 309 by 1965. With the classification into power class 3 from 1,500 to 1,999 hp, it had a low weight for a locomotive with six axles, which made it suitable for use on most branch lines.

The heart of the locomotives was the well-known diesel from English Electric, which was used here in the variant with twelve cylinders, turbocharger and intercooler. The distinctive exhaust sound led to the nickname “tractor” and is probably one of the reasons for the great popularity of the locomotives, some of which are still in use today, among enthusiasts. With a maximum speed of 90 mph, they were equally suitable for goods and passenger trains. For this reason, many locomotives were equipped with a steam boiler, the water tank of which was housed together with the fuel tank between the bogies. 

The boxes for displaying the four-digit train number, which were once found on almost all British locomotives, can be found on the class 37 in two distinctive designs. The earlier design, with two separate boxes, was mostly found in their initial service area of northern and eastern England and was referred to as a “split (headcode) box”. The later built machines only used a center box, more commonly seen in the South West and Wales. With the later conversions, the displays were removed and their lighting used as a headlight.

37 405 and 37 419 operated by Direct Rail Services in sandwich operation with only two passenger cars in December 2016 on the East Suffolk Line

Jeremy Segrott

With the introduction of more powerful locos, the class 37 became more widely distributed around the British Isles in line with current demand. In the Scottish Highlands, for example, they sometimes served almost all locomotive-hauled traffic, while in South Wales they were used to pull the heaviest coal trains. They were very well suited for these services because they had a high adhesive weight compared to their engine power.

Although British Railways phased out many first generation diesels in the 1980s, they could not do without the class 37 and modernized a large proportion of the stock. With the disappearance of steam-heated passenger cars, many locomotives were equipped with electric train heating, creating the subclass 37/4. Others were given new bogies for use in front of goods trains, which only allowed a top speed of 80 mph and thus increased the tractive effort. Some received additional ballast weights to increase adhesive weight. By eliminating the water tank for the steam heating system, the fuel capacity of many locomotives was almost doubled. With these modifications and various different adjustments to the electrics, the subclasses 37/3, 35/6, 37/6 and 37/7 were created in addition to the 37/4, while those that remained in their original condition were subsequently designated as class 37/0. A total of six locomotives were fitted with Mirrlees or Ruston engines in preparation for the development of new locomotives and listed as class 37/9.

Even after the privatization of the British rail system, a large number of class 37s continued to serve with different operators. Demand for passenger transport fell in the 1990s after a large number of Sprinter family diesel railcars had been completed. However, they were able to hold their own in front of goods trains for a long time, especially on routes with low axle loads, until these routes could be released piece by piece by locomotives such as the class 66. Special tasks include the use of departmental, construction or measurement trains and the transport of nuclear waste by Direct Rail Services. In addition to special trains, class 37 locomotives could sometimes still be seen pulling passenger trains after the turn of the millennium, especially when there was a shortage of DMUs. Between 2015 and 2019, passenger transport on the Wherry Lines in the Norwich region was also handled by DRS in sandwich operation with two of these locomotives and usually three passenger cars in order to still achieve good acceleration.

The Class 47 was produced in large numbers from 1962 to replace the last steam locomotives and therefore had to have an axle load of less than 20 tons. They were powered by a Sulzer twelve-cylinder engine with two cylinder banks. The initial 2,750 hp was soon reduced to 2,580 hp to improve reliability. Initially, most of the locomotives were given steam boilers, which were later replaced with electric train heating. This resulted in a large number of sub-variants that are used for passenger and freight trains and have a maximum speed of 75, 95 or 100 mph. A total of 33 locomotives were converted to Class 57 from 1998. The number of locomotives in use that have not been converted has now fallen significantly.

In the nineties, Freightliner was faced with the problem that their fleet of class 47 diesel-electrics was ageing and inefficient. Since the procurement of new locomotives would have been too expensive, they decided to rebuild the old locomotives and designate them class 57. Brush Traction took over the task to fit them with re-condtioned 12-cylinder EMD two-stroke engines and the traction alternators which are also used in the class 56.

Additional orders followed, which brought the number of rebuilt locomotives to 33. Aside from the standard freight variant with 2,300 hp, some were rebuilt as class 57/3 with 2,800 hp, electric train heating equipment and a higher top speed. Freightliner later sold its class 57/0 locomotives in favor of new-built class 66 locomotives.

Direct Rail Services needed a new diesel locomotive around 2010, which, in contrast to the widespread class 66, could also be used in passenger service and, above all, should have more comfortable cabs. An offer came from Vossloh España, which included a version of the EuroLight specially adapted for the British market. DRS received 34 locomotives in a total of three batches, of which the later ones were already delivered by Stadler.

The class 68 has only four axles and a light, fast-running Caterpillar engine with 2,800 kW or 3,800 hp. Despite the top speed of 100 mph (161 km/h), a starting tractive force of 71.000 pounds is achieved thanks to the three-phase traction motors. Some of the locomotives were equipped with push-pull train control so that passenger trains could be driven with driving trailers or in top-and-tail operation.

At DRS, the class 68 mainly pulls container trains, but also trains from the infrastructure operator Network Rail and nuclear flasks. Chiltern Railways, TransPennine Express and formerly Abellio ScotRail have also leased the class 68 from DRS for passenger service. TPE only plans to use the class 68 together with the modern driving trailers until December 2023 and replace it with railcars.