Ot1-18 (ex 41 316, MBAG 13275/1940), photographed near Jelenia Góra, date unknown. Written off in April 1970. Photo by Frank Engel (www.frank-engel.de) – thanks for permission!
DR class 41 side drawing by K.-E. Hertam (TB vol.1).
Development of the BR41: TCDD 46059, photographed at the Çamlık museum on
DRG 41 182, Orenstein & Koppel 13174/1938. Photo from my collection. This engine after WWII served with DR, later was re-designated 41 1182-9 and withdrawn in September 1986.
DR 41 1123-3 (formerly 41 123, BMAG 11062/1938), photographed in Magdeburg, Germany, on March 29, 1972. Photo by W. Kleiber (postcard from my collection). This engine was fitted with the modified boiler in 1959 and survived in service until 1983.
German soldiers posing in front of the 41 010 (Henschel 24312/1938), February 1941, location unknown. This engine remained with DB after the war; re-numbered 041 010-0, it was withdrawn in March 1968. Photo from my collection.
DB 41 360 (Jung 9318/1940) was re-boilered in 1958 and remained in use until May 1977. Sold to a private owner, it sometimes runs with DB special trains. Photo taken in Oberhausen on July 9, 2011, by someone who wants to be known as ‘Tenderlok’ (nice name!). Source: www.commons.wikimedia.org.
DR ‘Reko’ 41 1130 (ex DRG 41 130, BMAG 11069/1938), Saalfeld, May 14, 1971. Withdrawn in April 1987. Photo from my collection.
Another picture from Saalfeld: an unidentified BR41 in its original version (possibly withdrawn), date unknown. Photo from my collection.
‘Reko’ 41 150, DR (Schichau 3356/1938), Dessau, date unknown. Photo by H. Müller (from my collection). This engine was withdrawn in June 1993 and transferred to Bayerisches Eisenbahnmuseum, Nördlingen.
Yet another ‘Reko’ engine: 41 1180, DR (ex DRG 41 180, Orenstein & Koppel 13172/1938), photographed near Leuchtenburg, date unknown. This locomotive was withdrawn in November 1987. Photo by G. Feuereisen (postcard from my collection).
41 025, DRG (Henschel 24327/1938), RAW Frankfurt-Nied, 1939. After WWII with DR, transferred to Dampflokmuseum Hermeskeil in December 1991. Source: www.commons.wikimedia.org.
‘Reko’ 042 097, DB (ex 41 097, Krupp 191/1938), fitted with welded boiler and oil firing; Emden depot, date unknown. Withdrawn in December 1976. Photo by Hugh Llewellyn (source: as above).
German class 41 locomotive was designed in 1934 to fulfill the demand for a fast freight machine, capable of maintaining relatively high speed while not exceeding maximum axle load of 18 tonnes. It was intended to succeed DRG class 5620-29 (ex-Prussian G82, after 1945 PKP class Tr6). Four designs with the 1-4-0 axle arrangement were submitted to this specification by Henschel, Schwartzkopff, Schichau and Krauss-Maffei, but none of them found favor. It was found impossible to maintain moderate axle load with a sufficiently large (and heavy) boiler. The choice thus fell on a 1-4-1 engie, designed by Schwartzkopff – partly because it utilized the same boiler as the class 03 express locomotive then in production. This very type was standarized as BR (Baureihe, or class) 41, however, with boiler pressure increased from 16 to 20 bar. This demanded new materials and St47K steel was widely used. Soon it turned out that this steel was prone to premature ageing and after few years boiler pressure had to be reduced to 16 bar – the same was the case with several other types then in use with DRG. It should be noted here that experiments with even higher boiler pressure, then actively pursued in Germany, in general proved unsuccessful.
Class 41 featured drivers of untypical diameter – 1600 mm, larger than adopted in Germany for freight locomotives (1400 mm) but smaller than that of typical passenger machines (1750 mm). Furthermore, maximum axle load could be increased from 17.6 to 19.7 tonnes by simply repositioning bolts in levers connecting idle axes with driven axles. These features contributed to versatility: the machine could be used for fast freight trains as well as for passenger and even express ones, the more so that front Krauss-Helmholtz bogie facilitated easy running even at 100 km/h.
Two prototypes were built in 1936 and series production started in 1938 to last until June 1941, when war needs dictated shifting to more versatile locomotives of simplified design. Production machines differed from prototypes in some details, mainly concerning boiler accessories. In all, 366 examples were built by nine companies: Borsig (73), Esslingen (35), Henschel (86), Jung (40), Krauss-Maffei (18), Krupp (31), MBA – formerly Orenstein & Koppel (21), Schichau (37) and Schwartzkopff (25). Orders for further 24 machines from Schichau and 46 from Schwartzkopff were cancelled in 1941. Very soon these locomotives acquired a somehow contemptuous nickname of ‘Oschenlok’ (literally ‘ox loco’), as they were widely used with express freight trains transporting livestock.
In 1937, Turkish state railways TCDD ordered from Henschel eleven engines, derived from BR41, for fast passenger trains. These locomotives were slightly lighter and had modified boilers with larger superheaters; diameter of drivers was increased to 1750 mm and cylinder bore to 650 mm. Designated No.46051 through 46061, they served mainly at the Istanbul-Ankara line. No.46059 (Henschel 23659/1937) has been preserved at the steam locomotive museum in Çamlık.
After WWII most class 41 machines remained in Germany. 220 examples served with DB and DR had 119. One engine, 41 153, was taken over by Czechoslovak railways, but probably was not allocated a service number; in March 1955 it was transferred to an industrial operator. Soviets took six machines, but nothing is known about their further service. PKP took over 19 locomotives of this class (some sources give 18 – probably because the last one was accepted as late as in 1948). One more (41 076, Borsig 14797/1939) was handed over by DR in 1946, but this engine was not restored in service and had no PKP number. It was soon handed over to MPS (Soviet ministry of transport) and withdrawn in November 1948. According to the monographic article by Ryszard Stankiewicz (see References), seven examples were overhauled in Bydgoszcz in 1946 and saw brief service with PKP, which is not confirmed by www.beitraege.lokomotive.de. They retained their original DRG service numbers and in late 1946 were handed over to Soviet military railways, finally ending up with DR (one) and DB (six). Contrary to pre-war DRG practice, Polish locomotives of this type were used almost exclusively with passenger trains, hence their designation Ot1. Just as with those operated by DR and DB after WWII, boiler pressure was soon reduced to 16 bar, although some tests with higher pressure were in fact performed. Most Ot1s were used in Lower Silesia, but as electrification progressed, many of them were shifted to Lublin, to replace elderly and never entirely satisfactory Os24s. In early 1950s six examples were briefly based in Iłowo.
Premature ageing of boiler elements was an inherent flaw of these otherwise successful machines, therefore reconstruction was the only means to keep them in service. In Western Germany, 103 machines were fitted between 1957 and 1961 with new welded boilers of high efficiency, which radically changed their silhouettes. Forty of them were converted to oil firing and re-designated class 042; last of them was withdrawn in October 1977. Last original machines (not reconstructed – class 041) were written off in 1971. In Eastern Germany, 21 machines were fitted with reconstructed welded boilers (otherwise identical with the original ones) and, from 1961 onwards, eighty were rebuilt with entirely new boilers of indigenous design. Last DR machines survived in service until 1984. PKP had only nineteen Ot1s, so launching a dedicated reconstruction program was perhaps considered unjustified. Thus, when signs of intensified deterioration of material properties had been discovered during major overhauls in late 1960s, this meant a death sentence. All machines of this class were written off between August 1969 and March 1973; the last of them was Ot1-17 (ex DRG 41 313, Orenstein & Koppel 13272/1940). This meant that, in effect, these modern and efficient locomotives were outlived in service by older classes. Unfortunately, no Polish Ot1 has been preserved (nothing particularly shocking for a railway fan in Poland!). In contrast, as many as 23 machines of this type (most of them, if not all, in reconstructed versions) have survived in Germany. None of them, however, is fitted with original Wagner-type smoke lifters, which have been replaced by narrow Witte-type ones. Four of them (41 018, 41 144, 41 231 and 41 360) are in working order and there are plans to restore further two in service. 41 105 (Krupp 1927/1938) has had an eventful career: after 31 years with DB it was sold in 1976 to The Netherlands and served as a stationary boiler in Vlissingen until 1979. Sold to Stoom Stichting Nederland, Rotterdam, it was restored in service in 1980 and ran with special trains until 1991, when boiler ticket expired. There are plans to bring it back to the working order.
Main technical data
1) Some sources give 18 – probably because Ot1-19 was accepted later than other examples; one more not restored in service.
2) Initially 2.04 MPa, later reduced.
3) 1000 / 1000 mm for locomotives built by Borsig.
4) Repositioning of undercarriage lever bolts allowed for reducing weight on drivers to 70 000 kg and maximum axle load to 17.6 T.
List of vehicles can be found here.
References and acknowledgments
- Monographic article by Paweł Terczyński (SK vol. 2/2001);
- Monographic article by Ryszard Stankiewicz (SS vols. 151 and 152);
- TB vol. 1;
- http://www-personal.umich.edu/~khmiska (website by Kurt H. Miska – unfortunately currently not active);
www.beitraege.lokomotive.de (locomotive database by Ingo Hütter).