[2] In his first full season in British speedway, Lionel was a member of the Wembley Lions team that won the last ever Southern League and the National Trophy in 1931.

Van Praag also represented Australia in test matches at home against England on numerous occasions at tracks around the country including the Sydney Showground, Sydney Sports Ground, Wayville Showground (Adelaide), Claremont Speedway (Perth) and the Exhibition Speedway in Melbourne.

Van Praag was awarded the George Medal for bravery during World War II, when a Royal Australian Air Force Douglas DC-2, in which he was second pilot was shot down, by two Japanese aircraft over the Sumba Strait in Indonesia.

[4][5] Van Praag, a sergeant at the time, and the aircraft captain, Flying Officer Noel Webster helped two colleagues—one semi-conscious and the other a non-swimmer—to shore after spending thirty hours in the water during which they had to fight off several shark attacks.

[9] Van Praag also appeared in the 1933 British film Money for Speed which starred John Loder, Ida Lupino, Cyril McLaglen and Moore Marriott.