Spencer Horn was born in 1895, his parents having arrived back in England the day before!
He passed out from Sandhurst in 1914 and was commissioned as a 2nd lieutenant in the 3rd Dragoon Guards. He was promoted to lieutenant in 1915. In February 1916 he was seconded to the Machine Gun Corps, and then later to the Royal Flying Corps, becoming a flying officer on 3 April 1917.
He was assigned to 60 squadron, initially flying a Nieuport fighter, scoring his first victories in May. The squadron then upgraded to SE.5a planes, downing another enemy machine in August. He was then transferred out to form 85 squadron, leading the C flight from late August with the rank of acting Captain. After which he shot down another enemy plane. He was awarded the MC in October 1917. Following which he transferred home to become an instructor at Ayr.
In 1918 he went back to the front, scoring more wins, ending the war with seven enemy planes destroyed, and six driven down out of control. In December 1918 he was promoted to captain in the 3rd Dragoons returning to his original unit.
Between the wars he was stationed in India, then Tidworth, then India again. By 1931 he had been promoted to Major, and his unit then converted from cavalry to tanks becoming part of the Royal Armoured Corp in 1939.
He remained in India during the war, being promoted to lieutenant colonel in 1941. There is some evidence for him having been involved in the D-Day deception planning.
He retired in 1946. He died in Aldbourne in 1969