Jack Stewart Newcombe (1910-1931) was a British bobsledder who competed in the early 1930s.

He won the bronze medal in the four-man event at the 1931 FIBT World Championships in St. Moritz.

Newcombe was the brakeman and a member of the British and Royal Air Force bobsleigh team along with Pilot Officer Dennis Field (steersman), Pilot Officer Ralph Wallace and Pilot Officer Paddy Coote.

[1][2] After the World Championships Newcombe fell ill and died of Peritonitis on 26 Feb 1931.

[3] Newcombe passed through RAF Cranwell on 26 July 1930 from the same class as Douglas Bader.