The British Rail Class 16 also known as the North British Type 1 was a type of diesel locomotive designed and manufactured by the North British Locomotive Company. A total of ten were produced, these being numbered D8400-D8409.
The type was ordered by British Railways (BR) as an element of the 1955 Modernisation Plan. The design was largely derived from North British's earlier prototype locomotive, designated No. 10800, produced during the late 1940s; it also incorporated several engineering approaches common to steam locomotives, the company allegedly having difficulty transitioning to the new traction format. Akin to several other Type 1 designs, they were relatively compact locomotives that were intended primarily for local freight traffic. The performance of the type was found to be lacking in comparison with its peers, thus the potential for follow-on orders evaporated and no further examples were constructed beyond the original batch. The Class 16 shared numerous design features with those used on subsequent locomotives by the company, particularly the locomotive.
Background
In less than a decade following the formation of British Railways (BR), substantial changes were being made. Under the 1955 Modernisation Plan, a long-term strategy of replacing steam locomotives with a combination of diesel locomotives and electric locomotives was adopted, with the former being largely intended as an interim measure for most areas ahead of widespread electrification of trunk routes. There was also a strong political desire to support British manufacturers in transitioning towards the design and production of these favoured forms of traction. Due to a lack of expertise, this often involved the pairing of traditional locomotive manufacturers with various firms within the electrical sector, even though the latter typically had very limited experience of the railways.
In accordance with these policies, BR ramped up its efforts to convert its fleet, placing numerous orders within a short timeframe for diesel locomotives to several different specifications with various manufacturers. On 16 November 1955, a small order for ten Type 1 freight locomotives was placed with the North British Locomotive Company. Under BR's 'pilot scheme', such batches were intended for evaluation purposes under competitive conditions against rival designs in which the better models would receive follow-on orders.
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!Code ||Name ||Quantity
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|style="text-align:center" |30A ||Stratford ||style="text-align:right" |10
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!colspan=2 scope=row |Total:
|style="text-align:right" |10
|}
thumb|left|British Railways (BR) 10800 ordered previously in 1946 for London Midland & Scottish Railway (LMSR).
The design drew heavily upon North British's earlier prototype locomotive, designated No. 10800, which had been developed between 1947 and 1950. Having been ordered originally by the London, Midland and Scottish Railway prior to its absorption into BR, No. 10800 was designed for use on branch and secondary lines; according to railway historian Rodger Bradley, this early British diesel locomotive functioned not only as the direct predecessor of the Class 16, but can be more broadly considered to be the forerunner of all BR designs orientated towards this type of work up until the 1980s.