From 1951 to 1954, he studied at Douglas School of Art and Technology on the Isle of Man, and was then conscripted for two years' National Service in the Royal Artillery.
The plans for the 500 ft monument near Surrey Docks include a hollow pyramid containing laser-generated holograms and sounds recalling the Blitz, topped by sculptures of a Heinkel bomber and a Spitfire.
[citation needed] A major retrospective of his work was held at the Whitechapel Art Gallery in 1988 and then at the Wurttembergischer Kunstverein in Stuttgart in 1989.
[citation needed] Sandle designed the Belgrano Medal in 1986, which shows Margaret Thatcher, with the inscription "Imperatrix Impudens" ("Shameless Empress").
He resigned from the Royal Academy in 1997 in protest at the Sensation exhibition and the inclusion of Marcus Harvey's painting Myra, but rejoined in 2005.