Altitude of the Highest Manned Balloon Flight The Physics Factbook
Edited by Glenn Elert -- Written by his students An educational, Fair Use websiteBibliographic Entry Result
(w/surrounding text) Standardized ResultPiccard, Don. World Book Encyclopedia. USA: World Book, 1996. "1961, US Navy Officers Victor A. Prather, Jr and Malcolm Ross rose from a zero-pressure balloon at an altitude of 113,739.9 feet." 34,668 m
Crouch, Tom D. The Eagle Aloft: Two Centuries of the Balloon in America. Washington DC: Smithsonian, 1983. "May 4, 1961, M.D. Ross and V.C. Prather rose at the world record of 113,740 feet." 34,668 m
Perhaps it was just an Indian millionaire, bullock cart driver record?
The record setting flight in 1961 was a spectacular achievement, but a gas balloon was used, not a hot air balloon. Prather died at the end of the record-setting flight when they landed at sea. His flight suit filled with water and he drowned.