Bavarian A IV engines were German

2-2-2 Under the Whyte notation for the classification of steam locomotives, 2-2-2 represents the wheel arrangement of two leading wheels on one axle, two powered driving wheels on one axle, and two trailing wheels on one axle. The wheel arrangement both ...

steam locomotives A steam locomotive is a locomotive that provides the force to move itself and other vehicles by means of the expansion of steam. It is fuelled by burning combustible material (usually coal, oil or, rarely, wood) to heat water in the locomot ...

with the

Royal Bavarian State Railways The Royal Bavarian State Railways (''Königliche Bayerische Staats-Eisenbahnen'' or ''K.Bay.Sts.B.'') was the state railway company for the Kingdom of Bavaria. It was founded in 1844. The organisation grew into the second largest of the German ...

(''Königlich Bayerische Staatsbahn''). The vehicles were developed for night journeys and operations on the North-South Railway. In order to increase the area of the

evaporator An evaporator is a device used to turn the liquid form of a chemical substance, such as water, into a vapor. Uses Air conditioning and refrigeration Some air conditioners and refrigerators use a compressed liquid with a low boiling point, ...

, the

boiler A boiler is a closed vessel in which fluid (generally water) is heated. The fluid does not necessarily boil. The heated or vaporized fluid exits the boiler for use in various processes or heating applications, including water heating, central h ...

was increased in length to 3,080 mm and in diameter to 1,219 mm. In addition, the weight and the

overpressure were raised. These were the first engines to have an outside

frame A frame is often a structural system that supports other components of a physical construction and/or steel frame that limits the construction's extent. Frame and FRAME may also refer to: Physical objects In building construction *Framing (con ...

with outside cylinders. This class was used widely, especially in

south Germany Southern Germany () is a region of Germany which has no exact boundary, but is generally taken to include the areas in which Upper German dialects are spoken, historically the stem duchies of Bavaria and Swabia or, in a modern context, Bavaria ...

and in

Austria Austria, , bar, Östareich officially the Republic of Austria, is a country in the southern part of Central Europe, lying in the Eastern Alps. It is a federation of nine states, one of which is the capital, Vienna, the most populous ...

. All the engines bar one were retired by 1883. The survivor was initially converted to a

0-6-0 Under the Whyte notation for the classification of steam locomotives, represents the wheel arrangement of no leading wheels, six powered and coupled driving wheels on three axles and no trailing wheels. This was the most common wheel arrangemen ...

, and later a

0-4-2 Under the Whyte notation for the classification of steam locomotives, represents the wheel arrangement with no leading wheels, four powered and coupled driving wheels on two axles and two trailing wheels on one axle. While the first locomotiv ...

wheel arrangement In rail transport, a wheel arrangement or wheel configuration is a system of classifying the way in which wheels are distributed under a locomotive. Several notations exist to describe the wheel assemblies of a locomotive by type, position, and c ...

. They were coupled to 3 T 5 tenders.

See also