Pioneering Gemini, Apollo astronaut Thomas Stafford dies at 93

March 18 (UPI) -- Former Gemini and Apollo 10 astronaut Thomas Stafford died at his home in Indian Harbor, Fla., on Monday, NASA said. He was 93.

Stafford, a retired Air Force lieutenant general, was a test pilot during the early days of the U.S. space program, flew on the first Apollo-Soyuz mission and was head of NASA's astronaut office in the early 1970s, as well.

"Today, Gen. Tom Stafford went to the eternal heavens, which he so courageously explored as a Gemini and Apollo astronaut, as well as a peacemaker in the Apollo-Soyuz mission," NASA Administrator Bill Nelson said in a statement posted on the NASA website.

"Those of us privileged to know him are very sad but grateful we knew a giant," Nelson said. "Tom was critical to the earliest successes of our nation's space program and was instrumental in developing space as a model for international cooperation."

Stafford flew NASA's first space rendezvous on the Gemini 6 mission in 1965 and, Nelson said, in 1966 used pencil and paper to pilot the Gemini 9 mission back to Earth when a guidance system malfunctioned while in orbit.

Stafford also commanded the Apollo 10 mission in 1969. That mission, in which he and astronaut Gene Cernan flew less then 10 miles above the lunar surface, enabled the subsequent successful Apollo 11 moon landing later that year.

During Apollo 10's re-entry, Stafford, Cernan and John Young established a human speed record of 24,791 mph, equal to about 7 miles per second. The speed record still stands, according to the Stafford Air & Space Museum.

Young died at age 87 in 2018.

Stafford also commanded NASA's Apollo-Soyuz mission in 1975 that was the first international spacecraft rendezvous, and he became close friends with his Russian counterpart, Gen. Alexei Leonov. When Leonov died in 2019, Stafford delivered the eulogy during his state funeral in Russia.

Stafford was made brigadier general in 1975, which made him the first astronaut to achieve that rank, and was nominated for the Nobel Peace Prize for his part in the Apollo-Soyuz mission that year.

The Apollo-Soyuz mission is viewed by many the first step leading to the eventual end of the Cold War, and it made Stafford the only U.S. general to fly in space.

Before joining NASA, Stafford was an Air Force test pilot and flew more than 100 different types of aircraft during his career with the Air Force and NASA. He was a graduate of the U.S Naval Academy, where he graduated in the top 1% of his class and afterward transferred to the Air Force, according to KFOR4.

After leaving NASA following the Apollo-Soyuz mission, Stafford rejoined the Air Force, received more promotions, and became commander of Area 51 in the Nevada desert and later led the Air Force Research & Development and Acquisition wing in the Pentagon until his retirement in 1979.

Under Stafford's watch, the Air Force developed some of the nation's most significant aircraft, including the F-15 and F-16 fighters, the A-10 Warthog and the B-1B bomber. He also spurred development of stealth technology and created the specs for the F-117 Stealth Fighter and the B-2 Stealth Bomber, which earned him recognition as the "father of stealth."

Stafford was born in Weatherford, Okla., in 1930, where his namesake air and space museum is located. U.S. senators James Lankford and Markwayne Mulling and Representative Cyndi Munson, D-Oklahoma City, expressed their sadness at Stafford's passing in statements published by local media.

No cause of death has been announced.