The reference for locomotives and railcars
Nordhausen-Wernigerode Railway No. 51 and 52
German Reichsbahn class 99601
Germany | 1922 | 2 produced
Decorated locomotive for Walpurgis Night 1932 on the way to the Brocken
Decorated locomotive for Walpurgis Night 1932 on the way to the Brocken
Bundesarchiv, Bild 102-13442 / CC-BY-SA 3.0

The Nordhausen-Wernigeroder Eisenbahn, better known for the Brocken Railway in the Harz mountains, got two Mallets from Borsig in 1922 and 1924. They had a 2-4-4-2 wheel arrangement and were fairly heavy for meter gauge. Due to the very short rigid wheelbase of only 1,300 mm (4 ft 3 in), they had insufficient running characteristics and tended to derail. Furthermore, they were not reliable.

In 1949, both were taken over by the Reichsbahn as 99 6011 and 6012. They were put out of service in the Harz in 1956. 99 6011 was brought to the Gera-Pforten–Wuitz-Mumsdorf line and only used there for a brief period. It was ultimately retired in 1966, as it had been the case with 99 6012 already in 1964.

Built1922, 1924
Axle config2-4-4-2T (Skookum (Mallet)) 
Gauge3 ft 3 3/8 in (Meter gauge)
Dimensions and Weights
Length33 ft 11 1/2 in
Wheelbase25 ft 7 1/16 in
Fixed wheelbase4 ft 3 3/16 in
Empty weight95,901 lbs
Service weight116,845 lbs
Adhesive weight85,980 lbs
Axle load21,495 lbs
Water capacity1,585 us gal
Fuel capacity5,512 lbs (coal)
Power sourcesteam
Indicated power644 hp (480 kW)
Optimal speed18 mph
Top speed19 mph
Starting effort23,094 lbf
with start valve27,713 lbf
Power Plant
Driver diameter33.5 in
Boiler pressure203 psi
Expansion typecompound
Cylindersfour, HP: 14 3/16 x 15 3/4 in
and LP: 22 1/16 x 15 3/4 in
Grate area21.4 sq ft
Evaporative heating area924.5 sq ft
Superheater area236.8 sq ft
Total heating area1,161.3 sq ft
Calculated Values
steam locomotive
narrow gauge
last changed: 05/2024

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