Indian locomotive class HG. The Class HG (Heavy Goods) is a  goods steam locomotive, which was one of seven standard classes of broad gauge steam locomotives designed by the British Engineering Standards Association (BESA) for use in the British Raj in the mid-1900s.

This design was used by various railway companies of the British Raj, later passing on to Indian Railways and Pakistan Railways after the partition, the latter of which continued using these locomotives into the 21st century to haul the Khyber Steam Safari on the rugged Khyber Pass Railway.

History

The British Engineering Standards Committee (BESC, later renamed to the British Engineering Standards Association), founded in 1901, envisioned standardised locomotive classes for use in British India, to improve production and maintenance. In the second edition of the BESA report on British Indian standard locomotive classes of 1907, the HG class, designed for heavy goods trains, was first mentioned. As with the AP and HP class passenger locomotives, the HG was provided with three different tenders: the smaller 3000 gallon and 4000 gallon three-axle tenders, and the larger 4500 gallon bogie tender.

In addition, the 1907 BESA report also catalogued two variants: Variant A with  diameter driving wheels, which was proposed by the Indian Railways Ministry, and Variant B with  diameter driving wheels, in common with several other locomotives already in use on various railways, including the Bengal Nagpur Railway. Variant A, however, never saw production, and was excluded from the third edition of BESA's report in 1910.

From 1912, in common with other BESA designs, the HGS class was introduced, fitted with the Schmidt superheater - the S denotes superheated. The saturated HG locomotives that were later retrofitted with a superheater were given the classification of HGC - the C in the designation stands for converted. The superheated locomotives performed better than their saturated counterparts, as the latter were of British designs unsuited for the climate of the Indian subcontinent, due to their narrower fireboxes.

In 1947, after the British Raj was partitioned, 133 HG class locomotives of the North Western Railway ended up in the hands of Pakistan Railways. Indian Railways, who inherited the remainder, still had 168 HG class locomotives on the Central, Eastern, and South Eastern zones in June 1977, and were likely retired in the 1980s.

Pakistan Railways however, despite steam traction being mostly phased out in Pakistan in the 1990s, retained HGS 2216, 2277, and 2306 for use on the Khyber Pass Railway, where two of them worked top and tail on tourist trains to Landi Kotal, until 2006, when the railway suspended operations after monsoon rains damaged the line.

Preservation
Two of the Indian HG class locomotives have been preserved:
 HGS 26761 at the Rail Museum, Howrah
 Ex-NWR HGC 1598 (Vulcan no.2461) at the National Rail Museum, New Delhi

Four of the Pakistani HGS class locomotives are known to have survived, most recently used at a steam event around Attock in April 2020.

See also
 Indian locomotive class HP
 Indian locomotive class AP
 Indian locomotive class SG
 Indian locomotive class SP
 Indian locomotive class PT
 Indian locomotive class HT
 Locomotives of India
 Locomotives of Pakistan
 Khyber Train Safari
 Khyber Pass Railway
 Retirement of steam locomotives by country
 Steam locomotives of the 21st century

Notes

References 

Steam locomotives of India
Steam locomotives of Pakistan
5 ft 6 in gauge locomotives
2-8-0 locomotives
1′D h2 locomotives
1′D n2 locomotives
Railway locomotives introduced in 1907
Freight locomotives
Vulcan Foundry locomotives
NBL locomotives
Robert Stephenson and Company locomotives
Kitson locomotives
Beyer, Peacock locomotives