Key takeaways
- The 50.35 isn't a new-build locomotive but a reconstruction: 208 Class 50 engines received a completely new boiler from 1957.
- The new-build boiler of type 50E with combustion chamber gave noticeably more power than the original boiler.
- The sub-class .35 comes from the number range 50 3501 to 50 3708 – that's how the German class-numbering system works.
- Oil-fired engines ran as Class 50.50 and were redesignated Class 50.0 in 1970.
- No scheduled service any more: many engines are preserved in museums and count among the more frequently seen large steam locomotives.
Contents
Fact file
| Vehicle type | reconstructed freight tender locomotive of the Deutsche Reichsbahn |
|---|---|
| Original build | Class 50 locomotives |
| Wheel arrangement | 1'E h2 – one leading axle, five coupled driving axles, two cylinders |
| Conversion years | 1957 to 1962 |
| Conversion works | Raw Stendal |
| Quantity | 208 locomotives, running numbers 50 3501 to 50 3708 |
| Maximum speed | 80 km/h |
| Boiler | New-build boiler of type 50E with combustion chamber |
| Oil-fired variant | 72 engines from 1966 as Class 50.50, redesignated Class 50.0 from 1970 |
| Current status | no scheduled service, numerous engines preserved in museums |
Identifying features
Is this really the class in front of you?
- Five coupled driving axles with a single leading axle ahead, two outside cylinders
- Smooth, welded new-build boiler without the rivet rows of the original Class 50
- Running number in the range 50 3501 to 50 3708 – this gives the sub-class .35
- Witte-type smoke deflectors, tidied-up boiler fittings
- Oil-fired engines carry a closed tank instead of the open coal bunker
- Today runs exclusively ahead of museum, special and heritage trains
Updated: August 2026 – A freight locomotive with five coupled axles, but a strikingly smooth, welded boiler: this is Class 50.35, the Reko version of Class 50. 208 engines were built between 1957 and 1962 at the Raw Stendal works by giving existing locomotives a completely new boiler. This page explains what reconstruction means technically, how to recognise the engines, and where they still run today.
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What is Class 50.35?
Class 50.35 is a reconstructed freight tender locomotive of the Deutsche Reichsbahn. Between 1957 and 1962, the Raw Stendal works thoroughly rebuilt 208 Class 50 locomotives, fitting them with a newly manufactured boiler of type 50E with a combustion chamber. The engines carry running numbers 50 3501 to 50 3708 and kept the 80 km/h maximum speed and the 1’E wheel arrangement.
The gain lay in performance: the new boiler worked with better heating surfaces and markedly more effective combustion. That made the Reko engines noticeably superior to the original locomotives, without a complete new design being necessary. Today they run exclusively in museum and special-train service – there are no scheduled duties.
Reconstruction: the principle behind the sub-class
In the 1950s the Deutsche Reichsbahn faced a problem: ageing locomotives, tight funds, high demand for transport. The answer wasn’t new construction, but reconstruction.
Replace the boiler
The core of every reconstruction was a newly built boiler with a combustion chamber. It improved combustion and steam generation and was at the same time the most expensive component of a steam locomotive.
Keep the running gear
The frame, driving axles and running gear were essentially retained and overhauled. That saved time and material compared with a new build.
Modernise auxiliary equipment
Feedwater heaters, feed pumps and fittings were changed to newer types. That makes Reko engines noticeably tidier in detail than their predecessors.
Assign a new number group
Converted engines got their own serial numbers. The range from 3500 upward became the short form 50.35 – the same logic led to Class 52.80 for the war locomotives.
This pattern explains a whole family of designations: wherever the German class scheme has a number after the point, it almost always conceals a variant build – a conversion, a different origin, or different equipment. How to read such numbers in general is explained in the guide to identifying classes.
Reko or original?
The quickest test is the boiler surface. Pre-war original boilers show rivet rows; Reko boilers look smooth and welded. This is confirmed by the running number – serial numbers from 3501 upward point to a Reko engine.
Placing it in railway operations: what the Reko engines delivered
The 50.35 was the Reichsbahn’s workhorse for freight traffic on lines that couldn’t take a heavy locomotive. The following overview places it in context.
| Class | Origin | Boiler | Special feature |
|---|---|---|---|
| 50 | new-build 1939–1948 | original boiler, riveted | low axle load, very broad route clearance |
| 50.35 | conversion 1957–1962 | new-build boiler 50E, welded | more power at the same wheel arrangement |
| 50.50 / 50.0 | conversion from 1966 | new-build boiler, oil-fired | closed oil tank instead of coal bunker |
| 52.80 | conversion from 1960 | new-build boiler 50E | reconstruction of the Class 52 war locomotive |
| 44 | new-build from 1926 | original boiler | three-cylinder design, heaviest freight duties |
The comparison shows how systematically the Reichsbahn proceeded: the same boiler type migrated into several classes. That’s why the Reko war locomotives of Class 52.80 and the 50.35 look similarly modernised at first glance. The original build remains Class 50, while the three-cylinder Class 44 took a completely different path.
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Spotting: where Reko engines run today
Because many engines survive, the 50.35 is one of the steam locomotives you can actually expect to see with a bit of planning. Heritage operators such as the Eisenbahnfreunde Traditionsbetriebswerk Staßfurt keep such engines operational. The route there runs via the operators:
- Heritage railways and preservation societies in eastern Germany maintain a large share of the surviving engines. Their vehicle lists are generally published.
- Season and event calendars. Running days, museum festivals and anniversaries are announced well in advance. The overview on researching heritage railways shows where these dates appear first.
- Special-trip listings. For runs on the general network, the guide to special trains and special trips is worthwhile.
- Community reports. They show the day-to-day picture and reveal short-notice locomotive changes. How to usefully report your own observations is covered in the guide to reporting sightings.
Photographically, it’s worth looking at the boiler with Reko engines: the smooth, welded surface reflects differently from a riveted one and copes better with soft side light than harsh midday sun. Everything else on steam-train photography is in the guide how to photograph steam trains.
House rules apply on museum grounds
Tracks, engine sheds, turntables and workshop areas are operational railway land and must not be entered. Barriers and staff instructions are binding, even at organised photo events. Stick to designated locations or publicly accessible areas; the basic rules are in the article on the safe distance from the track.
Also practically relevant is the difference between preserved and operational engines. A locomotive already counts as preserved if it stands somewhere as a monument or waits in a shed for restoration. The Eisenbahnmuseum Bayerischer Bahnhof zu Leipzig, for instance, shows such shed stock. It’s only operational once it has a valid boiler certificate, and that expires after a few years. Because a general overhaul on a large steam locomotive is costly, engines regularly switch between the two states. Lists that simply note “preserved” therefore say little about whether you can actually experience the locomotive under steam.
For planning this means: don’t search for the class, search for the specific running number. Operators usually communicate deadlines and workshop stays per vehicle, and it’s exactly this information that decides whether a trip is worthwhile.
Common mix-ups
It points to the 50.35 if …
- you count five coupled axles with a single leading axle ahead
- the boiler looks smooth and welded, without rivet rows
- only two outside cylinders sit on the frame
- the running number lies in the range 50 3501 to 50 3708
Look more closely if …
- the engine looks modernised but you can't read the number – the 52.80 also carries a 50E boiler
- the tender has no coal superstructure – then it's an oil-fired engine
- a preserved locomotive has been deliberately returned to a different state
It's not a 50.35 if …
- a third cylinder works between the frame plates
- the boiler clearly shows rivet rows
- you count only four coupled axles
Conclusion
Class 50.35 is a textbook example of how the German class-numbering system works: the number after the point reveals the variant build, here the conversion with a new-build boiler. In the field you recognise it by the smooth boiler cladding and the number from 3501 upward. And because so many engines survive, it’s one of the more accessible German large steam locomotives for spotters.
In short
1'E, two cylinders, smooth new-build boiler, number from 50 3501: that's the Reko Class 50.35. It doesn't run to a timetable, but turns up comparatively often at heritage railways and special trips.
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Summary
- Class 50.35 shows the principle of reconstruction: upgrading existing vehicles with new boilers instead of building new locomotives.
- In the field it's distinguished from Class 50 above all by the smooth, welded boiler and the number range.
- Because the Reichsbahn deployed many of these engines right up to the end of steam traction, an above-average number survived.
- For spotters, it's therefore one of the more realistic chances to experience a German large steam locomotive under steam.
Frequently asked questions
What does reconstruction mean for a steam locomotive?
From the 1950s, the Deutsche Reichsbahn thoroughly rebuilt existing locomotives instead of procuring new ones. The core of the conversion was usually a completely new boiler with better heating surfaces and a combustion chamber. The chassis and running gear stayed essentially the same – the result was a significantly more powerful engine at lower cost.
How do I recognise a Reko engine of Class 50.35?
By the smooth, welded boiler without the rivet rows of the original engines, and by the running number in the range 50 3501 to 50 3708. Wheel arrangement and cylinder count match the original class: five coupled axles, one leading axle ahead, two outside cylinders.
How many Class 50.35 locomotives are there?
208 engines were converted between 1957 and 1962 at the Raw Stendal works. Because they stayed in service with the Reichsbahn right up to the end of steam traction, an above-average number survived. The exact preserved fleet keeps changing through restorations and sales.
Why is it called Class 50.35 and not something else?
Because the sub-class derives from the number range. The engines carry numbers 50 3501 to 50 3708, i.e. serial numbers from 3500 upward – hence the short form 50.35. In the German system, the number after the point always marks a variant build within the same class.
What's the difference from the regular Class 50?
The basic design is the same: 1'E, two cylinders, 80 km/h. But the Reko engines have a new-build boiler of type 50E with a combustion chamber, which enabled better combustion and more power. Visually the smooth, welded boiler cladding stands out above all.
What was Class 50.50?
That's how the Reichsbahn ran the oil-fired Reko engines. 72 locomotives were converted to oil firing from 1966. In the 1970 computer-based renumbering, they moved into the Class 50.0 range. Externally you can recognise them by the closed oil tank on the tender instead of the open coal bunker.
Does Class 50.35 still run today?
Not in scheduled service. Numerous engines are preserved in museums, some of them operational and regularly deployed ahead of special and museum trains. Whether a particular engine is running right now depends on boiler certificate deadlines, workshop schedules and the operating society's finances.
How do I find out where Class 50.35 is running?
Via the event calendars of heritage railways, the pages of operating societies, and special-train listings on railway forums. Community sightings add the day-to-day picture. Fixed timetables don't exist – check again shortly before you set off whether the announced engine is really running.
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Related classes
Class 50
Class 50 is the most successful German freight steam locomotive: over 3,000 built, five coupled axles, low axle load. Today it only runs in heritage service.
Steam/specialClass 52.80
Class 52.80 is the rebuilt version of the wartime Class 52: 200 locomotives with a new boiler, converted from 1960. Today one of the most common museum steam locomotives.
Steam/specialDR/DB Class 44
The Class 44 was the heavy freight locomotive of the standard-design classes: five coupled axles, three cylinders, around 1,989 built. The "Jumbo" now only runs in preservation.
Steam/specialClass 01.10
The Class 01.10 was the three-cylinder development of the 01: 55 engines, streamlined from the factory, rated for 150 km/h. Today only seen as a heritage vehicle.
Steam/specialDR Class 01.5
The Class 01.5 was created by rebuilding the old standard Class 01 at the Meiningen works: new boiler, modernised cab, some engines converted to oil firing – today they are museum vehicles only.
Steam/specialDRG Class 03
The Class 03 was the lighter sister of the 01: same wheel arrangement 2'C1', same top speed, but a lower axle load – so it could run on far more lines.
Who is behind it
Groups, brands, manufacturers and operators – who owns whom and how to recognise them out in the field.
Eisenbahnfreunde Traditionsbetriebswerk Staßfurt
In Staßfurt, a society keeps a complete locomotive depot alive: roundhouse, turntable, workshop and a collection made up mostly of East German vehicles. Not a museum behind glass, but a site where work happens – and which is accessible on open days.
Heritage railwayEisenbahnmuseum Bayerischer Bahnhof zu Leipzig
At the Bayerischer Bahnhof in Leipzig stands Germany's oldest surviving terminus station – and alongside it a society maintains a collection of operational and under-restoration vehicles. The site combines two things that rarely coincide: the earliest railway history and active steam operation.
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