View source for Prussian S 6

{{Short description|Class of German steam locomotives}}
{{refimprove|date=December 2014}}
{{Infobox locomotive
| name             = Prussian S 6<br/>DRG Class 13.10–12<br/>PKP Pd 5<br/>SNCB Type 66
| bgcolor          = 000000
| color            = FFFFFF
| image            = Pd 5-17 Warszawa Tech.Kol. 06.04.05.JPG
| caption          = Pd 5-17
| builder          = [[Linke-Hofmann-Busch|Linke-Hofmann]] (330)<br/>[[Henschel-Werke|Henschel]] (173), [[Maschinenbauanstalt Humboldt|Humboldt]] (81)<ref name="LBF">[http://www.lbforum.com/lbf1-00.htm Länderbahn-Forum] {{webarchive|url=https://web.archive.org/web/20081019122337/http://www.lbforum.com/lbf1-00.htm |date=2008-10-19 }}</ref>
| builddate        = 1906–1913
| totalproduction  = 584
| whytetype        = [[4-4-0]]
| DRGtype          = 2 24.18
| gauge            = {{track gauge|1435mm|allk=on}}
| leadingdiameter  = {{convert|1,000|mm|in|2|abbr=on}}
| driverdiameter   = {{convert|2,100|mm|in|2|abbr=on}}
| over bufferbeams = {{convert|18,350|mm|ftin|1|abbr=on}}
| axleload         = {{convert|17.6|t|abbr=on}}
| serviceweight    = {{convert|60.6|t|abbr=on}}
| weightondrivers  = {{convert|34.7|t|abbr=on}}
| fuelcap          = 
| watercap         = {{convert|21.5|m3|impgal USgal|abbr=on}}
| boilerpressure   = {{convert|12|bar|kPa psi|abbr=on}}
| fireboxarea      = {{convert|2.35|m2|sqft|abbr=on}}
| evaporativearea  = {{convert|136.98|m2|sqft|abbr=on}}
| superheaterarea  = {{convert|40.32|m2|sqft|abbr=on}}
| cylindercount    = 2
| cylindersize     = {{convert|550|mm|in|2|abbr=on}}
| pistonstroke     = {{convert|630|mm|in|2|abbr=on}}
| maxspeed         = {{convert|110|km/h|abbr=on}}
| indicatedpower   = {{convert|679|kW|abbr=on}}
| fleetnumbers     = DRG 13 1001–1286
| retiredate       = 1931
}}

The '''Prussian S 6''' (later '''DRG Class 13.10–12''') was a class of German [[steam locomotive]] with a [[4-4-0]] wheel arrangement operated by the [[Prussian state railways]] for [[express train]] services.

==Development==
After the Prussian steam locomotive classes [[Prussian S 4|S 4]] and [[Prussian S 5|S 5]] proved less than fully satisfactory, there was a requirement in [[Kingdom of Prussia|Prussia]] for faster and more powerful express locomotives. To that end the Head of the Locomotive Design and Procurement Department, [[Robert Garbe]], proposed to the Locomotive Committee in 1904 a design by [[Linke-Hofmann-Busch|Linke-Hofmann]] of [[Breslau]] for a 4-4-0 superheated, [[express train]] locomotive. This was an evolutionary development of the Prussian Class S 4 that also had a 4-4-0 configuration.<ref name="LBF" />
In putting this forward, Garbe was especially keen to prove the superiority of his design compared with the four-[[cylinder (locomotive)|cylinder]], saturated steam, [[compound locomotive|compound locomotives]], particularly its predecessor, the Prussian Class [[Prussian S 7|S 7]].<ref name="LBF" /><ref name="DLB">[http://www.dampflok-willi.de/beschreibung.htm#s6 Dampflok-Beschreibungen, pr. S6]</ref>

In 1905/1906 Garbe pushed through the construction of the S 6. Between 1906 and 1913 a total of 584 units were manufactured by [[Linke-Hofmann-Busch|Linke-Hofmann]],  [[Henschel-Werke]] and the [[Maschinenbauanstalt Humboldt]] in Cologne. They were the last four-coupled, express locomotives to be built in Germany and, for a long time, were the most economical locomotives in the Prussian state railways.<ref name="LBF" />

==Design features==
The design initially caused major difficulties, because it had to keep to the maximum permitted [[axle load]] for the railway network of {{convert|16|t|1|abbr=on}}.

This limitation led to the weight savings in many areas. At first, the [[plate frame]] was made of {{convert|22|mm|in|2|abbr=on}} thick material; this later had to be changed to the usual {{convert|25|mm|in|2|abbr=on}}. On the first few engines, a [[smokebox]] superheater was installed, but the design this was changed during the first year in favour of a [[Heißdampf-Schmidt|Schmidt]] smoke tube [[superheater]]. The long [[boiler]] was located well forward in order to spread the weight to the front [[carrying wheels]] and to keep the axle load within the maximum limits, thus giving the engine the typical appearance of a "Garbe locomotive".

The [[driving wheels]] of the S6 had the rather unusual [[diameter]] of {{convert|2,100|mm|in|2|abbr=on}} in order to keep the rpm down and to guarantee the smooth running of the driving gear. Originally a diameter of {{convert|2,200|mm|in|2|abbr=on}} had been planned, but in the end, it was reduced by {{convert|100|mm|in|2|abbr=on}}. The heavy balancing masses of the driving gear were badly affected by weight savings. That resulted in serious jerkiness when running. A remedy was achieved by coupling the [[tender (rail)|tender]] closer to the locomotive and thus raising the compression of the buffer springs.<ref name="LBF" />

Not until the lines were upgraded in 1910 to take a {{convert|17|t|1|adj=on}} axle load, could the necessary reinforcing measures be taken. The S 6 then became the heaviest 4-4-0 locomotive on continental Europe, even outweighing the subsequently built four-cylinder, saturated steam locomotives of Class [[Prussian S 7|S&nbsp;7]].

The driver's cab was initially built with a tapered front and conical smokebox doors in order to reduce wind resistance. An unfortunate side effect of the streamlined driver's cab, however, was that the engine crew were dazzled at night by reflections from the diagonally oriented front windowpanes. From 1908/1909 the cab was built with a flat front.

The locomotives were equipped with Prussian Class pr 2’2’ T 21.5 [[tender (rail)|tenders]].

==Performance==
The S 6 achieved its highest indicated power of 1,160 PS ({{convert|870|kW|abbr=on|disp=or}}) at a speed of {{convert|100|km/h|abbr=on}}. On the level it could haul a train of {{convert|500|t}} (the equivalent of 13 eight-wheeled [[D-Zug]] coaches) at a continuous speed of {{convert|90|km/h|abbr=on}}. On engines with a feedwater preheater the performance was about 10% higher.<ref name="LBF" /><ref name="DLB" />

==Distribution==
{| class="wikitable" width="500" align = "right"
|+ style="padding-bottom:1em;" | Initial allocation of S 6 
|- class="hintergrundfarbe5"
! width="20%" | [[Eisenbahndirektion|Division]] !! width="10%"; align="center"| Quantity <br/> of S6 !! width="20%" | Division !! width="10%"; style="text-align:center"| Quantity <br/> of S6 !! width="20%" | Division !! width="10%"; align="center"| Quantity <br/> of S6 
|-
| Altona || style="text-align:center"|70 || Elberfeld || style="text-align:center"|23 || Kattowitz || style="text-align:center"|21
|-
| Breslau || style="text-align:center"|44 || Erfurt || style="text-align:center"|17 || Magdeburg  || style="text-align:center"|41
|-
| Bromberg || style="text-align:center"|31 || Essen || style="text-align:center"|31  || Mainz || style="text-align:center"|9
|-
| Cassel || style="text-align:center"|10 || Frankfurt || style="text-align:center"|5 || Münster  || style="text-align:center"|45
|-
| Coeln || style="text-align:center"|27 || Halle ||style="text-align:center" | 68 || Posen || style="text-align:center" | 35
|-
| Danzig || style="text-align:center"|21 || Hannover ||style="text-align:center" | 42 || Stettin || style="text-align:center"|44
|}
[[File:Prussian S 6 locomotive at Camp Williams, Is-sur-Tille, France, 9 June 1919 (111-SC-159657).jpg|thumb|641 Halle at Camp Williams, Is-sur-Tille, France, in June 1919. This one would become locomotive 6641 of the Belgian State Railways and ran until 1949<ref name="Locs"/>.]]
Apart from the [[Eisenbahndirektion|divisions]] of Berlin and Königsberg (other sources also name Saarbrücken), the S 6 was procured by all the Prussian railway divisions S 6. There were only a few transfers.<ref name="LBF" />

After the [[First World War]] the S 6 was employed in express train duties (on the Leipzig–Dresden, Berlin–Dresden and other lines) as well as in passenger train services. Many of the engines were rehomed at Dresden.

==Preserved locomotives==
From 1912 the S 6 was ousted from heavy express train services by the S 10.

In the 1923 [[DRG renumbering plan for steam locomotives]], 442 S 6 engines were listed for renumbering into the 13 1001 to 13 1442 series. In the third and final renumbering plan only 286 engines were listed: numbers 13 1001 to 13 1286.<ref name="LBF" />
The last engines in Germany were retired between 1926 and 1931.

After [[World War I]], 81 locomotives were handed over to [[Poland]] (class Pd5), 42 to [[Belgium]] (type 66), two to [[Italy]] (class 553) and one to [[Lithuania]] as [[World War I reparations|reparations]].<ref name="DLB"/>

The engines in those countries survived considerably longer in service; in Belgium they were not retired until 1949.<ref name="Locs">{{cite web| url=https://www.tassignon.be/trains/documentation/repertoire.php?type=32@224| title=Etat Belge - Type 66 | work=Tassignon.be - Repertoire - Locs | language=fr}}.</ref>

During the [[Second World War]], a total of 56 S 6 came back into the [[Reichsbahn]] fleet from Poland as numbers 13 501-556.

One S 6 has been preserved in [[Warsaw]] (Poland).

==See also==
* [[Prussian state railways]]
* [[List of Prussian locomotives and railcars]]
* [[List of preserved steam locomotives in Germany]]

==References==
{{reflist}}
*{{Hütter-01bis45|pages=117–118, 124–129}}
*{{Weisbrod-EFA1.1|pages=81–83}}
*{{Vandenberghen-SNCB12.2|pages=61–68}}

==External links==
{{Commons category|Prussian S 6}}
* [http://www.dampflok-willi.de/images/s6foto.jpg Photo of locomotive in original configuration]
* [http://www.dampflok-willi.de/images/s6strich.jpg Drawing with dimensions]

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{{DEFAULTSORT:Prussian S 06}}
[[Category:Locomotives of Prussia|S 06]]
[[Category:4-4-0 locomotives]]
[[Category:Railway locomotives introduced in 1906]]
[[Category:Passenger locomotives]]
[[Category:Standard-gauge locomotives of Germany]]
[[Category:Linke-Hofmann locomotives]]
[[Category:Henschel locomotives]]
[[Category:Humboldt locomotives]]
[[Category:2′B h2 locomotives]]