The Dynamic .049 was a brave and technically very successful 1961 attempt by a British company calling itself Dyedesyne Ltd. to design a ¹/₂A diesel which could compete with the new high-performance ¹/₂A glow-plug motors then emerging from American manufacturers. This superb little twin ball-race rear drum valve motor was designed by Gordon Cornell, who had previously worked with George Fletcher at International Model Aircraft (FROG) and then served as chief engineer at E.D. for a time. Gordon had tried to persuade E.D. to introduce a new model along these lines, but they had opted instead for the rather lacklustre E.D. Pep intead - one of a number of factors which led to Gordon's resignation in late 1960.

As far as Gordon could later recall, only about 20 examples of this model were produced before financial difficulties forced Dydesyne founder Alan Dye out of business. There were also a few examples of a radially-mounted plain bearing FRV model called the Tutor. Further details of the Dyedesyne engines may be found on Ron Chernich's "Model Engine News" (MEN) web-site.