Whitehorn's early career was as a crewman on North Sea helicopters and also with the Thomas Cook travel agency. In 1987, Whitehorn joined the Virgin Group after being talent spotted by Sir Richard Branson. He had suggested a number of ideas to Virgin the previous year, in 1986, whereupon the company recruited him formally. He rose to become the head of Virgin's public affairs department. In that role, where he was effectively the official spokesperson for the company, he was sometimes characterized as Richard Branson's "right-hand man". He was, until recently, president of Virgin's space program Virgin Galactic but had to leave due to the relocation of the testing area.
- Mather, Adrian (2004-10-08). First Edinburgh man in space. Retrieved on 2009-05-08 from http://news.scotsman.com/ViewArticle.aspx?articleid=2570336.
- "First Edinburgh Man in Space". Red Orbit. 2004-10-10. Retrieved 2007-11-19.