Class G5 Locomotive History
Following his appointment as NER Locomotive Superintendent (latterly referred to as the Chief Mechanical Engineer), Wilson Worsdell reversed his brothers small passenger tank design policy and went back to the 0-4-4 wheel arrangement, similar to Fletcher’s G6 of 1874. The Class ‘O’ (in NER locomotive class format) was designed in 1893 as a replacement for the Class A (2-4-2) with smaller driving wheels but with larger coal and water capacity, giving it a greater range.
The first of the class emerged from the NER North Road Works, Darlington, in 1894 and by 1901, when production ceased, the class totalled 110 examples built in 7 distinct batches. They became the standard NER passenger tank locomotive until 1907 when larger classes, such as the A8, were introduced.
During their 60 years plus lifetime the G5’s underwent several modifications but all of them minor. The most important visual change was to move the ‘Westinghouse’ house pump from the inside of the cab to the front or left hand tank. From 1917 the NER fitted ‘cages’ on top of the coal bunker to help increase the capacity with an extension added on top of the cage from 1921 to further increase coal capacity, and the change from Ramsbottom safety valves (with the distinctive brass trumpet) to Ross pop valves.
In 1923 the NER became the largest and most profitable constituent of the LNER and the Class ‘O’ became Class G5 in that company’s locomotive class system.
From 1930 the LNER introduced a new boiler design, type 69, with a single plate barrel and 199 tubes. This was further modified in 1937 with an increase in boiler tubes up to 207; the dome was moved back about 20 inches and was classified as 69A.
From 1932 about a quarter of the class received hopper extensions for use with the new mechanical coaling plant being belatedly introduced by the LNER.
One locomotive, 387, has the side tanks modified to provide extra water capacity for use in the Hull area on what were termed “lightweight express trains”. The experiment does not appear to have been a success as no other locomotives were altered.