Joseph William Kittinger Jr. was an American test pilot, United States Air Force officer and aviation pioneer whose work in high-altitude ballooning contributed significantly to aerospace research and to the development of safe escape systems for high-altitude flight.

He was born in Tampa, Florida, on 27 July 1928. He graduated from the Bolles School in Jacksonville, Florida, and attended the University of Florida. Entering military service in March 1949 as an aviation cadet, he was commissioned a second lieutenant in March 1950 at Las Vegas, Nevada. From 1950 to 1953 he served as a jet pilot with the 86th Fighter-Bomber Squadron in Germany before being assigned to the Air Force Missile Development Center (AFMDC) at Holloman Air Force Base, New Mexico, where he became involved in high-altitude balloon research.

On 2 June 1957, while stationed at the AFMDC, then Captain Kittinger made a balloon flight to 96,000 feet in the first flight of the Air Force's Project Manhigh, preceding Lt. Col. David Simons, who reached 102,000 feet, and 1st Lt. Clifton McClure, who ascended to 98,000 feet. For his Manhigh I flight he was awarded the Distinguished Flying Cross.

After his assignment to the Aerospace Medical Research Laboratories at Wright-Patterson Air Force Base, Dayton, Ohio, Kittinger was appointed Test Director of Project Excelsior, which investigated emergency escape from extreme altitude. During the project he made three parachute descents from balloon-supported gondolas: from 76,400 feet on 16 November 1959, from 74,700 feet twenty-five days later, and from 102,800 feet on 16 August 1960, then the highest altitude from which a man had jumped. He remained in freefall for 4½ minutes, reaching speeds of up to 714 mph in temperatures as low as ?94°F before deploying his parachute at 18,000 feet. In addition to the altitude record, he established records for the longest freefall and the highest speed attained by a man without an aircraft. For this work he received the C.B. Harmon Trophy, presented by President Dwight D. Eisenhower on 3 October 1960, an oak leaf cluster to the Distinguished Flying Cross, the John Jeffries Award, the Leo Stevens Parachute Medal and the Wingfoot Lighter-Than-Air Society Achievement Award.

On 13–14 December 1962, accompanied by astronomer William C. White, Kittinger ascended to 82,200 feet over Holloman Air Force Base as part of Project Stargazer. During the 18.5-hour flight, the balloon served as a platform for astronomical observations to evaluate variations in the brightness of star images caused by the Earth's atmosphere.

Kittinger volunteered for three combat tours in Vietnam and served as commander of the 555th Tactical Fighter Squadron ("Triple Nickel"), flying the F-4 Phantom II. He shot down a MiG-21 before being shot down himself on 11 May 1972, after which he spent eleven months as a prisoner of war. He remained in the Air Force until his retirement as a colonel in 1978.

After retiring from military service, Kittinger joined Martin Marietta Aerospace as an engineer while returning to competitive ballooning. He won the Gordon Bennett Gas Balloon Race in 1982, 1984 and 1985 before undertaking a solo crossing of the Atlantic Ocean. On 14 September 1984 he launched from Maine in the helium balloon *Rosie O'Grady*. Flying more than 3,500 miles at altitudes between 10,000 and 17,000 feet, he completed the crossing in three and a half days, crash-landing in northern Italy on 18 September. The flight established records for the longest solo balloon flight and the greatest distance flown in its class.

Over the following decades Kittinger remained active in ballooning. Although he declined many requests along the years to be part or support attempts on his 1960 stratospheric records, in 2010 he joined the Red Bull Stratos project as Felix Baumgartner's mentor and capsule communicator. The 2012 mission surpassed several of the records established during Project Excelsior while leaving Kittinger's freefall duration record intact. He also promoted ballooning and aerospace education through lectures, mentoring and his support of educational initiatives, including the Civil Air Patrol's National High Altitude Balloon Challenge.

In 2011 he co-authored his autobiography, “Come Up and Get Me”, with Craig Ryan.

Joseph Kittinger died in Orlando, Florida, on 9 December 2022, aged 94.