The London, Midland and Scottish Railway (LMS) Princess Royal Class is a class of an express passenger steam locomotive designed by William Stanier. They were Pacifics (i.e. had a 4-6-2 wheel arrangement). Thirteen examples were built at Crewe Works, between 1933 and 1935 and two are preserved.

A prototype batch of three locomotives was to be constructed in 1933. Two were constructed as drawn but the third set of frames was retained as the basis for an experimental turbine locomotive.
The third prototype was constructed with the aid of the Swedish Ljungstrom turbine company and known as the Turbomotive, although not named. It was numbered 6202, in sequence with the Princess Royals. Although 'generally similar' to the rest of the Princess Royals, and 'not all that much different', it used a larger 40 element superheater to give a higher steam temperature, more suitable for turbine use. This boiler was also domeless as would later be used for the second batch of the Princess Royals. The continuous exhaust of the turbine, rather than the sharper intermittent blast of the piston engine, also required changes to the draughting and the use of a double chimney. It entered service in June 1935 on the London–Liverpool service.

This Turbomotive was rebuilt in 1952 with conventional 'Coronation' cylinders and named Princess Anne, but was soon destroyed in the Harrow and Wealdstone rail crash.