The LMS Hughes Crab or Horwich Mogul is a class of mixed-traffic 2-6-0 steam locomotive built between 1926 and 1932. They are noted for their appearance with large steeply angled cylinders to accommodate a restricted loading gauge.

Designed by George Hughes, Chief Mechanical Engineer of the LMS, and built at the ex-L&YR works at Horwich and the ex-LNWR works at Crewe. The inspiration came from a Caledonian Railway 2-6-0 design at the grouping; however, the cylinders were too large for the LMS's English section's loading gauge, resulting in Hughes having to adapt the concept. They were put into service by his successor, Henry Fowler. The design incorporated a number of advanced features for the time such as long travel valves, compensated brake gear, a new design of tender and a new boiler, the latter based on the one fitted to Hughes's four-cylinder Baltic tank locomotives built at Horwich. 

When an order was placed by the traffic department for delivery of 40 more examples of this type, the new Chief Mechanical Engineer, William Stanier, decided to introduce a taper boiler version, in line with his policy of using taper boilers on all new locomotive designs. There were so many changes to the layout of the locomotive, such as higher boiler pressure and smaller cylinders, that it became a new design, the LMS Stanier Mogul.

The class survived intact until 1961 when three were withdrawn. The remainder of the class were withdrawn over the next six years. Of the 245 built, three have survived to preservation