JŽ 133-005 is ex-KkStB 73.372 (StEG 3286/1906). Photo was taken at the Lublana railway museum on June 18, 2009.




KkStB 73.79 (Wiener Neustadt 3169/1887) later became ÖBB 55 5708 and currently is awaiting restoration at Heizhaus Strasshof; photo taken on June 20, 2009.




 KkStB 73.416 (BMMF 309/1909) was transferred to PKP and numbered Tp15-194. Taken over by DRG in 1939, it was re-numbered 55 5854; returned after the war, remained in service for a few more years as Tp15-2. Postcard from my collection.




KkStB 73.14, WLF 569/1885, became ČSD 414.004 in 1918 and survived in service until May 1968. Location and date unknown (postcard from my collection).




KkStB 73.284 (WLF 1280/1899), location and date unknown, probably before 1914. This locomotive later became ČSD 414.079, then DRG 55 5789. Returned after the war, it remained in service until March 1965. Source:



Side drawing of ČSD class 414.0; source: EZ vol. 2.



An unidentified Class 73 locomotive, location and date unknown. Source: Die Lokomotive February 1932.

The most numerous PKP locomotive of Austro-Hungarian origin was class Tp15 – former kkStB class 73. In all, over 230 engines of this type were taken over after WWI. This certainly gives them a place in the history of Polish railways, although not a single Tp15 has survived until today.

Origin of this class may be traced back to the year 1884, when the Arlbergbahn was completed. This important line was characterized by steep gradients, up to 31‰ – a great challenge in those times. Axle load was not to exceed 14 tonnes, so four coupled axles were considered mandatory from the very beginning. First contenders, built by Wiener Neustadt (Nos. 501 through 504, later kkStB class 76), Krauss of Munich (Nos. 505 through 509, later kkStB class 78) and WLF (tank engines Nos. 510 and 334, later kkStB class 79) were rejected and in 1885 WLF proposed a new design, initially classed BF IV and – compared to the earlier ones – characterized by internal frame. The latter feature allowed for larger cylinder bore and hence increased tractive effort of 11.2 tonnes, not a mean achievement for this time, especially with moderate boiler pressure of only 11 bar. This type was finally accepted for production. Until 1909, as many as 453 examples were built by BMMF (37), Krauss Linz (17), StEG (119), WLF (194) and Wiener Neustadt (86). They were numbered from 7301 through 7599 and then from 17301 onwards. When new designation system was introduced in 1905, it was decided that last two digits should match those of the old numbers. Thus, 7599 was re-numbered 73.299 and 17301 became 73.301; there was no 73.300 and the last engine built was 73.454, so some sources give 454 as the total number built. The majority went to kkStB, but smaller numbers were also built for various private railways – all these engines had also kkStB service numbers.

Although winning large production contracts, 73s were by no means star performers. With large firebox, no rear idle axle and comparatively short axle base running qualities left much to be desired and maximum speed, initially set at 40 km/h, was later reduced to a mere 35 km/h. However, these engines were capable of hauling a 200-tonne draft on a 25‰ gradient at 12 km/h and indeed were among the most powerful European locomotives with four coupled axles. They remained the most important freighters in the kkStB service until class 170, with the tractive effort of 11.6 tonnes and better running qualities, became available in quantity in early 1900s. There were some minor differences between individual batches; in particular, 73.149 had the pressure reduced to 10 bar, while 73.151 and 152 – increased to 12 bar. Externally 73s could be easily distinguished by a large steam dome and a saddle-type sandbox immediately behind it. They were usually fitted with large Rihosek-type spark arresters, typical for many Austrian engines.

After WWI, Austrian state railways BBÖ kept only 44 engines of this type; after the Anschluss they became DRG class 5557. Czechoslovakian state railways ČSD took over 120 examples, classed 414.0 – in 1938 most of them shared the fate of their Austrian kinsmen. Italian state railways FS obtained 25, classed 424: last were withdrawn in 1931. 21 were transferred to Romania, where they were impressed into the CFR service with original numbers; last were withdrawn in 1937. Four went to the Kingdom of Serbs, Croatians and Slovenians (later class 133) and seven were lost in Russia. According to some Russian sources, class designation ChG was provided for captured 73s (ЧГ in Russian script – Ch stood for ‘chetyrekhosnyi’, or four-axle, and G for ‘Galitsya’, the region where they served), but it is doubtful if it was ever in fact assigned. In fact, Russian troops captured a number of Austrian locomotives during the 1914 offensive, but very little is known on their subsequent fate.

According to LP, Poland took over 233 examples, of which at least 219 were classed Tp15 and given new service numbers. There are some discrepancies between various sources. According to, 73.170 (StEG 2301/1893) became Tp15-87 and 73.418 (BMMF 311/1909) went to ČSD. LP does not confirm the former and states that the latter went to PKP, but its service number (if assigned) is not known. Finally, according to EZ, 73.418 became Tp15-196, which is not consistent with LP, which gives that this PKP number was assigned to 73.419. Most probably fourteen 73s handed over to Polish authorities were either damaged or in very poor condition, so they had already been withdrawn when new PKP designation system was introduced in mid-1920s. Over ten engines of this type were armored at railway workshops in Nowy Sącz and Lwów and used with armored trains during fights with Ukrainians and Soviets in early 1920s (six kkStB numbers are known). Later they were returned to PKP and restored in service, with the exception of 73.367 (StEG 3281/1906), which was most probably withdrawn from use.

Tp15 was considered a sturdy and useful machine of good manufacturing quality, but soon approached obsolescence. As many as 99 examples were withdrawn from the PKP service before 1936 and twenty more followed until September 1939. Immediately before WWII this class was assigned to regional railway managements in Kraków and Lwów. As with most types of Austro-Hungarian origin, based at depots in southern and south-eastern Poland, in 1939 most fell into Soviet hands – 54 in all, plus one already withdrawn. Some were later re-gauged and used with Polish service numbers, written in Russian script. Germans captured 35 engines and impressed them into DRG class 5557,58. Further 41 followed after the attack on the Soviet Union: some remained with Ostbahn and other were given DRG numbers. Most served in Austria and Czechoslovakia.

After the war, thirteen engines were returned and given new PKP service numbers. Nine more followed from Austria between 1947 and 1949, plus two from Czechoslovakia in 1959. In 1953, Tp15-121 was returned by MÁV; this engine was initially erroneously designated Tp1-98 and later became Tp15-26, but was written off a few months later. Of fifteen examples that returned from Germany and Yugoslavia (some as late as in the mid-1950s) only Tp15-209 was re-numbered Tp15-25, but similarly saw little service, if any; the rest were scrapped without being given new service numbers. Post-war service of these elderly engines was inconspicuous and comparatively short: last were written off in 1956.

Three 73s have survived until today. 133-005 (ex kkStB 73.372, StEG 3286/1906) can be seen at the railway museum in Lublana and ÖBB 55.5708 (ex 73.79, Wiener Neustadt 3169/1887) is awaiting restoration at the Heizhaus Strasshof, Austria. ČSD 414.096 (ex 73.368, StEG 3282/1906) was for a long time plinthed in Česke Velenice. In spring 2014 it was transported to Lužná u Rakovníka, to be restored to the working order. First test rides took place in May 2019.


Main technical data







Years of manufacture


1885 – 1909


Total built / used in Poland


453 / 2331)


Tender class




Axle arrangement




Design maximum speed




Cylinder bore


2 x 500


Piston stroke




Engine rating


490 / 665


Tractive effort


11 800


Boiler pressure




Grate dimensions

m X m

2.25 m2


Firebox heating surface




Distance between tube plates



Number of flue tubes




Heating surface of flue tubes




Number of smoke tubes




Heating surface of smoke tubes




Evaporating surface, total




Superheater heating surface




Diameter of drivers




Diameter of idlers front/rear


- / -


Total weight, empty


47 500


Total weight, working order


55 100


Weight on drivers, working order


55 100


Weight with tender, empty



Weight with tender, working order


87 000


Maximum axle load




Axle base (with tender)


10 680


Overall length (with tender)


16 518


Brake type




1)      Only 219 given PKP service numbers.

2)      Limit imposed due to uneasy running.

3)      ČSD modification: 190 flues, 155.3 sq.m.


List of vehicles can be found here.


References and acknowledgments


- (Ingo Hütter’s database);

- (website by Josef Pospichal);

- (website by Michał Derela – information on armored engines);

-       LP, EZ vol. 2, EDÖ, ITFR;

-       Josef Pospichal (private communication);