GNRI Class BT

Great Northern Railway Class BT
File:GNRI Class BT No. 1 at Irish Street in 1909.jpg BT No. 1 at Irish Street Halt, Armagh, 1909
Type and origin Power type Steam Designer J.C. Park Builder Dundalk works Build date 1887 Total produced 13
Specifications Configuration: ​  • Whyte 4-4-0T Gauge 5 ft 3 in (1,600 mm) Driver dia. 4 ft 7 in (1,397 mm) Boiler pressure 160 lbf/in2 (1,103.16 kPa) Cylinders Two, inside Cylinder size 15 in × 20 in (380 mm × 510 mm) Train heating steam
Career Operators GNR(I) Number in class 13

Great Northern Railway Class BT were a class of 13 4-4-0T tank locomotives introduced by the GNR(I) from 1887. They were the Great Northern Railways first home built engine and therefore the first engine to be built in Dundalk works.

While fit for purpose when built, increasing train weights particularly with bogie carriages a factor meant by the 1920s they were underpowered for all available work and were withdrawn by 1921.