After commencing research in theoretical physics he switched his attention to Numerical Analysis and Programming, spurred on by his close contact with the construction of the EDSAC prototype computer in the Mathematical Laboratory, under Maurice Wilkes.

Hugh McGregor Ross records[2] that "George Felton tells how, when Pegasus was new, he would borrow a front door key on Friday evenings so he could get in during the weekends.

[a] The team at Ferranti included [4] Bill Elliott, Conway Berners-Lee, Christopher Strachey, Charles Owen, Hugh Devonald, Henry Goodman and Derek Milledge.

Following the mergers Felton ran the division responsible for the operating system and basic software for the 1900 Series.

One of their sons, Matthew Felton, moved to the United States and became one of the designers of the Microsoft Windows NT operating system.