 From mid-1954 at Ferranti's London Computer Centre Felton led the team developing innovative and comprehensive operating system and programming software for the Ferranti Pegasus and Orion computers.Hugh McGregor Ross records 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.Then, alone in the building, he would start up the computer to sum a series to calculate the value of π to a then record 10,024 decimal places.