The Helston Railway Diesel Group (HRDG) was set up in November 2005 by a group of members from The Helston Railway Preservation Society (HRPS). The HRPS are working towards restoring a section of the Helston Branchline in west Cornwall and returning it to use as a 'heritage railway'. The HRDG was formed by those keen to see diesel traction in use on this line and were fairly quick off the mark getting their first 'traction'.

On March 17th 2006 the group announced they had purchased a class 103 'Park Royal' DMU and fund raising began in ernest.