Key takeaways
- The 2016 is a modern ÖBB diesel locomotive based on the Siemens ER 20 platform, nicknamed Hercules.
- ÖBB class logic: the leading 2 of a four-digit class marks a diesel locomotive.
- ER 20 is legible: EuroRunner with a power class of around 2,000 kW.
- Fastest field feature: no pantograph, but a radiator and exhaust on the roof instead.
- Deployment areas change with electrification schemes, contract awards and timetable years.
Contents
Fact file
| Vehicle type | Four-axle diesel-electric main-line locomotive |
|---|---|
| Nickname | Hercules |
| Manufacturer designation | Siemens ER 20 (EuroRunner, around 2,000 kW) |
| Designation system | ÖBB Class 2016 – leading 2 means diesel locomotive |
| Wheel arrangement | Bo'Bo' (two two-axle bogies) |
| Maximum speed | 140 km/h |
| Years built | from the 2000s onward |
Identifying features
Is this really the class in front of you?
- No pantograph on the roof – that immediately rules out any electric locomotive
- Four axles in two bogies, compact body
- Visible radiator and exhaust equipment on the roof
- Class marking starts with 2016 – the leading 2 stands for diesel locomotive
- Typically seen ahead of trains on non-electrified lines and on engineering-train duty
Updated: August 2026 – Austria is a highly electrified railway country – and still needs diesel locomotives. The Class 2016, known in the community as the Hercules, is the ÖBB’s modern answer to this task. This page shows you how to recognise it in seconds, what the manufacturer code ER 20 reveals, and what a diesel locomotive is even needed for in an electrified network.
Spotted a diesel locomotive? Note it straight away.
Diesel locomotives often run outside the standard diagrams – all the more reason to document them with number, location and date.
What is the ÖBB Class 2016?
The Class 2016 is a four-axle diesel-electric main-line locomotive of the ÖBB with a Bo’Bo’ wheel arrangement, rated for 140 km/h. It belongs to the Siemens platform ER 20 (EuroRunner). Its established nickname is Hercules.
Diesel-electric means: the diesel engine drives a generator, whose current supplies the traction motors at the axles. This design allows very fine control of tractive effort – an advantage when starting heavy trains and on the gradients that are the rule in Austria.
Two codes, two pieces of information: Class 2016 and ER 20
Almost every modern rail vehicle carries two designations. Reading both saves you a lot of looking things up.
ÖBB class: the vehicle type
A four-digit number with the word "Class". The first digit tells you what it is: 1xxx electric locomotive, 2xxx diesel locomotive, 4xxx electric multiple unit, 5xxx diesel railcar.
ER: the platform
EuroRunner, Siemens's diesel locomotive line. Vehicles from this platform run at several railways across Europe, each under its own operator number.
20: the power class
An indication of around 2,000 kW. Anyone who knows the code has the order of magnitude at once, without opening a data sheet.
UIC number: the individual vehicle
Twelve digits, beginning with the type code – typically 92 for diesel locomotives – and the country code 81 for Austria.
You’ll find the same platform in Germany under the designation Siemens ER 20. How to generally get from the vehicle type via the axle count to the specific class is described in the guide to identifying rolling-stock classes.
Why an electrified network needs diesel locomotives
This question comes up often – and the answer is surprisingly varied.
| Task | Why an electric locomotive isn’t possible |
|---|---|
| Non-electrified lines | No overhead line present |
| Engineering-train and maintenance duty | Overhead line switched off in the work area |
| Shunting away from the overhead line | Siding tracks without overhead line |
| Fallback in case of faults | Loss of power supply on line sections |
The fastest look for identification
Look at the roof first. A pantograph present means electric locomotive, a radiator and exhaust mean diesel locomotive. This feature works at great distance, in rain and against the light – and it immediately cuts the number of possible classes by more than half.
Older representatives of this family of tasks are the Class 2143 and the closely related ÖBB Class 2143, which shaped main-line diesel duty for decades. How to generally spot the right features on diesel locomotives is shown, using the German example, by the article on older diesel locomotives of Classes 218 and 232.
Diesel workings are hard to plan for
Live-reported sightings are often the only reliable source of information for engineering and special workings.
Placement in railway operations
For spotters, diesel locomotives differ fundamentally from electric ones in clock-face services. Their workings follow demand more than the timetable.
- Less predictable. Engineering trains, trip workings and special duties don’t appear in the timetable book. Where a machine runs tomorrow depends on construction planning, not on the clock-face pattern.
- Different times of day. Work under a switched-off overhead line often takes place during possession periods – frequently at night or at weekends.
- Different locations. Branch lines, siding connections, construction site areas. These are rarely the classic photo locations on main lines.
- Highly changeable. Every electrification scheme changes the range of tasks. What’s diesel-worked today may be run electrically within a few years.
Taken together, these points mean: anyone specifically searching for diesel locomotives works with current reports rather than annual plans. When work takes place under a switched-off overhead line is set by ÖBB-Infrastruktur via its possession periods. The guide to the ÖBB live train radar for Austria shows which tools help with this.
Diesel-electric or diesel-hydraulic – why it matters
With diesel locomotives, there are two fundamentally different ways of getting the engine’s power to the wheels. The difference explains a great deal about why particular classes were procured for particular tasks.
Diesel-hydraulic means: a hydraulic transmission, a so-called torque converter, sits between the engine and the axles. This design was the European standard for decades because it’s light and comparatively compact. Older Austrian main-line diesel locomotives mostly belong to this category.
Diesel-electric means: the engine drives a generator, whose current supplies traction motors at the axles. Mechanically this is more elaborate, but electrically very elegant – tractive effort can be regulated steplessly and extremely finely. That pays off precisely when starting heavy trains and on long gradients, because tractive effort can be matched precisely to the available adhesion.
There’s a second advantage besides: the drive technology resembles that of a modern electric locomotive. Traction motors, converters and control follow the same principles, which simplifies development, spare-parts holding and training. The Class 2016 belongs to this modern diesel-electric generation.
For you on the platform, the difference isn’t directly visible, but it is audible: diesel-electric machines accelerate more smoothly, without the noticeable gear changes of a hydraulic transmission.
Spotting and photography
Diesel locomotives are photographically rewarding because they often run slowly and stand in unusual places. At the same time, the same rules apply as everywhere else.
- Choose a publicly accessible location. Platforms and public paths, yes. Tracks, operational railway land, construction site areas and stabling sidings are closed off and life-threatening – without exception and regardless of how quiet it looks there.
- Prefer a three-quarter view. About 30 to 45 degrees to the vehicle axis shows the front, side wall and marking at the same time.
- Get the roof in too. The radiator equipment and exhaust are the characteristic detail on a diesel locomotive. A slightly elevated vantage point pays off.
- Watch for exhaust plumes. Pulling away under load produces visible exhaust plumes – a subject that simply doesn’t exist with electric locomotives. The exposure basics for this are in the guide to good photos of trains.
Common mix-ups
It points to the Class 2016 if …
- no pantograph sits on the roof, but a radiator and exhaust do
- the marking begins with 2016
- the locomotive has four axles in two bogies and looks modern
Look more closely if …
- a very similar-looking machine from another keeper is in front of you – the ER 20 platform is widespread
- the vehicle is running in a company livery
- a country code other than A appears next to the number
It's not a 2016 if …
- a pantograph sits on the roof – then it's an electric locomotive
- the class marking begins with 1
- the vehicle is a railcar with a passenger compartment – then the class falls in the 5xxx range
The second point in particular is relevant in Austria. The ER 20 platform was delivered in several variants, and in cross-border traffic as well as on engineering workings, vehicles from private keepers are everyday sights. The ÖBB’s own freight workings, on the other hand, mostly run for the ÖBB Rail Cargo Group. The keeper marking next to the twelve-digit number is therefore just as important as the class number.
Conclusion
The Class 2016 shows that diesel traction has a fixed role even in a heavily electrified network – wherever no overhead line is available or can be used. It can be recognised in seconds via the roof, placed via the class number, and its platform designation ER 20 reveals the power class in the same breath.
In short
No pantograph, four axles, marking 2016: the ÖBB's modern diesel locomotive based on the Siemens ER 20. Its workings follow demand, not the clock-face pattern – anyone searching for it works with current reports.
Capture the rare workings too
Engineering trains and special trips don't repeat – document them with number, location and date.
Summary
- The Class 2016 covers the tasks at the ÖBB for which no overhead line is available or can be used.
- The manufacturer code ER 20 reveals the platform and power class, the ÖBB class number the vehicle type.
- For identification, a glance at the roof is enough: no pantograph means diesel.
- Because diesel locomotives often run on engineering-train and branch-line duty, their deployment locations are less predictable than in clock-face services.
Frequently asked questions
What is the ÖBB Class 2016?
The Class 2016 is a four-axle diesel-electric main-line locomotive of the ÖBB, designated by the manufacturer as Siemens ER 20 and known in the community as the Hercules. It has a Bo'Bo' wheel arrangement, is rated for 140 km/h, and takes on tasks on non-electrified lines as well as in engineering and special duty.
Why does the class number begin with a 2?
Because the ÖBB encodes the vehicle type in the first digit of the four-digit class number. 1xxx means electric locomotive, 2xxx diesel locomotive, 4xxx electric railcar or multiple unit, 5xxx diesel railcar. The 2016 is therefore recognisable as a diesel locomotive from the number alone.
What does the designation ER 20 mean?
ER stands for EuroRunner, Siemens's diesel locomotive platform, and the 20 for the power class of around 2,000 kW. Manufacturer codes like this are helpful because the same platform runs at various railways under entirely different operator numbers.
What does diesel-electric mean?
The diesel engine doesn't drive a mechanical or hydraulic transmission but a generator. Its current supplies traction motors at the axles. The advantage lies in the fine controllability of tractive effort, which counts especially when starting heavy trains and on gradients.
How do I tell a diesel locomotive apart from an electric one?
By the roof. An electric locomotive carries at least one pantograph; a diesel locomotive has radiator equipment and an exhaust instead. This feature works from a great distance and in poor light – considerably more reliably than any shape feature.
Where are diesel locomotives needed in Austria?
On non-electrified lines, in engineering-train and maintenance duty, for work under a switched-off overhead line, and in shunting away from the overhead line. How large these tasks turn out to be changes with electrification projects and contract awards – this is explicitly subject to change.
How do I identify the individual machine?
Via the full twelve-digit UIC number. For diesel locomotives, the type code 92 comes first, followed by the country code 81 for Austria. Together with the ÖBB class marking, this identifies every vehicle unambiguously.
Does the 2016 also run outside Austria?
The ER 20 platform was delivered in various versions to several railways and private operators, so you may encounter very similar-looking machines in neighbouring countries too. Whether a specific locomotive is Austrian is settled by the keeper marking next to the vehicle number.
Log your sighting of the ÖBB Class 2016 (Hercules)
Date, location and vehicle number logged in seconds – and visible to the community.
Related classes
ÖBB Class 2143
The Class 2143 was the ÖBB's standard mainline diesel for decades. Here's how to recognise it by its roof, its axle count and its four-digit class number.
Diesel locoÖBB Class 2143
Why the ÖBB say "Reihe" instead of Baureihe, what 2143 reveals, and how to identify locomotives that moved to private keepers after the state-railway era.
Diesel locoSiemens ER 20
The Siemens ER 20 Eurorunner is one of the few modern diesel locomotives in Germany that also hauls passenger trains – with a diesel-electric three-phase drive.
Who is behind it
Groups, brands, manufacturers and operators – who owns whom and how to recognise them out in the field.
ÖBB-Infrastruktur
ÖBB-Infrastruktur owns the tracks, points, signals and most stations in Austria – but not a single train in the timetable. That's exactly why locomotives from companies with no connection to ÖBB roll over the Brenner, Semmering and Tauern lines.
State railwayÖsterreichische Bundesbahnen (ÖBB)
ÖBB isn't a single company but a group made up of passenger transport, the Rail Cargo Group and infrastructure. If you're spotting in Austria, you can't avoid the four-digit class scheme – it tells you the traction and design before you've even properly identified the vehicle.
GroupÖBB Rail Cargo Group
The Rail Cargo Group is ÖBB's freight division – and at the same time an umbrella brand that holds no licence of its own. Trains are actually run by Rail Cargo Austria and a string of national companies whose codes appear in the data panel, while only RCG is written on the outside.
Where to see the ÖBB Class 2016 (Hercules)
Specific viewpoints with lighting times, coordinates and an honest verdict on whether the trip is worth it.
Innsbruck Hauptbahnhof
Innsbruck is the only place in Austria where the Brenner axis, the Arlberg line and the Lower Inn Valley line meet. The result is a station where locomotives are constantly being moved, coupled and set up – against a mountain backdrop no other main station can match.
Junction stationSalzburg Hauptbahnhof
Salzburg is the station where two networks overlap: German traffic from Munich arrives from the north, the Westbahn from the east, and the Tauernbahn branches off to the south. Hardly anywhere else do German and Austrian rolling stock stand side by side so regularly.
Related guides from the blog
