 The new classes were designed by Robert Riddles , who had previously designed the WD Austerity 2 @-@ 8 @-@ 0 and WD Austerity 2 @-@ 10 @-@ 0 locomotives for wartime use . The first design requested by the Railway Executive was for a new express passenger " Pacific " locomotive , designed specifically to reduce maintenance and using the latest available innovations in steam technology from home and abroad . Various labour @-@ saving devices were utilised to produce a simple , standard and effective design , able to produce equivalent power to some of the " Pacifics " that were still available as legacies of the Big Four . 
