Leonardo da Vinci (Auld Mortality's universe)
From Tardis Wiki, the free Doctor Who reference
In a parallel universe, Leonardo da Vinci was a 15th century Italian inventor who travelled with the Doctor and his granddaughter Susan. (AUDIO: A Storm of Angels; PROSE: The Innocents)
In 1480, the Doctor took Leonardo to visit the Ore, a race who had ships which travelled by astrodynamic principles derived from the harmonies of the Spheres. This experience allowed Leonardo to master the power of flight, altering history so that humanity had developed spaceflight by the 16th century. (AUDIO: A Storm of Angels)