Class E 16

Updated: August 2026 – Few locomotives give themselves away as quickly as the Class E 16: large round drive discs sit on one side of the vehicle, and not on the other. Once you’ve seen this picture, you don’t forget it. This page explains what’s behind it and how to correctly place and photograph the vehicle.

What is Class E 16?

The E 16 is an express-train electric locomotive that AEG built in 21 examples between 1926 and 1933. It has the wheel arrangement 1’Do1’ – four coupled driving axles between two carrying axles – and runs at 15 kV, 16.7 Hz. At the Deutsche Bundesbahn it later ran as Class 116.

Its technical unique selling point is the Buchli drive. Instead of mounting the traction motor directly on the axle, it sits sprung within the frame; the power travels to the driving wheel via a large, externally mounted disc mechanism. On the E 16, this mechanism is arranged on only one side of the vehicle. The result: one and the same locomotive looks like two different vehicles from the left and from the right.

The fastest identification there is among electrics

With modern classes you have to compare fronts and read numbers. With the E 16, a glance at the right side is enough.

If you want to work through such features systematically and in the right order, the guide to identifying classes helps.

Placing it: drive technology as an identifying feature

The drive solution was the defining design feature of electric locomotives right into the 1950s. It only vanished from view once bogie construction took over. The following table places what you see on which type of vehicle.

Class	Visible drive	Carrying axles	Typical era
E 16 with Buchli drive	yes, strikingly one-sided	present	1920s and 1930s
Other classic electrics	partly, rods or spring cans	mostly present	1920s to 1940s
Post-war electric like Class 110	no	absent	1950s and 1960s
Modern three-phase locomotive	no	absent	from the 1980s onwards

How great the difference is shows up in a direct comparison with the Class 110 (E10): there a smooth body on two bogies, here a machine that puts its mechanism on open display.

Photo tips: why one side isn’t enough

The E 16 is the rare subject where a single photo misrepresents the locomotive. Anyone who only photographs the other side ends up with an unremarkable classic electric in the can – and misses the actual point.

The basic technique – choosing a viewpoint, light, composition – is covered in the guide to good photos of trains. How to file the pictures afterwards so you can still find them in years to come is in the article on a photo archive for spotters.

Why the drive sits on the outside at all

At first glance, the Buchli drive looks like an unnecessarily complicated solution. In fact, it solved a real problem that every fast electric locomotive of the early era had.

A traction motor is heavy. If it sits directly on the axle, its weight is accelerated unsprung with every rail joint and track irregularity. That stresses the track and the vehicle and limits the permitted speed. For slow freight locomotives that was acceptable; for express locomotives it wasn’t.

The solution was to mount the motor sprung within the locomotive frame and transmit the power to the driving wheel via a movable linkage. That’s exactly what the striking disc mechanism does: it allows the axle to move relative to the motor without the power transmission breaking off. The price for that is space – and that space was only available outside the frame, meaning visibly on the side of the vehicle.

The fact that this mechanism sits on only one side on the E 16 has the same cause: it’s large, and two such arrangements would have made the vehicle unnecessarily wide and heavy. The result is a vehicle with two faces – a gift for photographers, a challenge for model builders. Anyone wanting to document both sides should plan a visit to where such machines are permanently on show, for instance at the Bavarian Railway Museum in Nördlingen.

With post-war bogie construction, the problem disappeared. Modern drives are compact enough to be housed inside the bogie; unsprung masses can be limited in other ways by design. That’s why today’s locomotives show nothing of the drive technology on the outside any more. Anyone wanting to understand how strongly technology shapes appearance will find the E 16 the best illustration German electric locomotive building has to offer.

Common mix-ups

The streamlined express locomotive of the same era is found under Class E 18, the design relative under Class E 17.

Conclusion

The E 16 is perhaps the most rewarding classic electric for beginners: its most important feature sits on the outside, is large, and can’t be missed. At the same time it shows how strongly drive technology used to determine a locomotive’s appearance. Anyone photographing it should take the trouble to document both sides – otherwise the picture only tells half the story.