SECR N1 Class - Operational Assessment

Operational Assessment

The N1 was a capable class of mixed-traffic locomotive that could operate over the Southern Railway's gauge-restricted routes and was noted by crews for its comfortable riding qualities. The class also provided Maunsell and his assistants with a precedent for other compact 3-cylinder locomotive designs and formed a mechanical template for the Southern Railway's K1 class tank engine of 1925. However, the prototype offered little improvement in performance over the N class when tested on non-restricted routes, which led to an initial reluctance within the management of the Southern Railway to authorise batch construction. This meant that the non-standard Holcroft valve gear proved expensive to maintain because of the consequent lack of spare parts.

The use of three separate sets of valve gear on the 1930 batch eased maintenance and improved the standardisation of parts. The prototype was rebuilt to the same specification as the 1930 batch, creating a robust workhorse capable of a good turn of speed when working heavy passenger and freight trains. The revised valve gear layout was subsequently applied to the 3-cylinder U1 and V class designs. The relatively early withdrawal of the N1s pre-dated the era of preservationists buying withdrawn locomotives from scrap dealers or British Railways, and consequently no examples of the N1 class survived into preservation.