The fifth and youngest son of Jeff Tracy (the founder and financier of International Rescue), Alan is named after American astronaut Alan Shepard. Sources differ on the subject of Alan's age and date of birth; in the Thunderbird Fact File, his birthday is stated to be 12 March 2044, making him 21 years old during the events of most of the series. An accomplished sportsman and former racing driver, he can at times be bad-tempered and reckless.[3] Alan studied at Colorado University, where his natural impetuousness led to a clash with authorities over the launch (and subsequent crash) of an unsanctioned, self-built rocket. His father took charge of the situation, steering the interest toward more constructive ends, ultimately resulting in Alan's role as astronaut and principal pilot of Thunderbird 3.
The episode "Move ~ And You're Dead" revealed that Alan is additionally a skilled racing car driver, but that he gave up this career to assume his responsibilities within International Rescue. In "Alantic Inferno", Alan pilots Thunderbird 1, assuming his brother Scott's role of flying to the danger zone and co-ordinating the rescue operation. Alan commented on how different it was from operating Thunderbird 3, prompting Scott to remind him to "bring [Thunderbird 1] back in one piece". In the film Thunderbird 6, he shoots three hijackers, becoming one of only three members of IR (with Scott and Gordon) to kill an enemy. The most romantic of all the Tracy brothers, Alan is involved with Tin-Tin - the daughter of Kyrano, caretaker of Tracy Island.[3] However, despite his passion for her, he is seen to be attracted to IR's London agent, Lady Penelope Creighton-Ward, in the episode "The Perils of Penelope" and the film Thunderbirds Are Go.[3]