[7][8] World War II began while Grissom was still in high school, but he was eager to join the armed services upon graduation.

Grissom enlisted as an aviation cadet in the U.S. Army Air Forces during his senior year in high school, and completed an entrance exam in November 1943.

[9] Grissom was discharged from military service in November 1945, after the war had ended, and returned to Mitchell, where he took a job at Carpenter Body Works, a local bus manufacturing business.

Upon completion of the program, he was assigned to Williams Air Force Base in Mesa, Arizona, where his wife, Betty, and infant son, Scott, joined him, but the family remained there only briefly.

[13] He flew one hundred combat missions during approximately six months of service in Korea, including multiple occasions when he broke up air raids from North Korean MiGs.

[14] Grissom was also awarded the Distinguished Flying Cross and the Air Medal with an oak leaf cluster for his military service in Korea.

During a training exercise with a cadet, the trainee pilot caused a flap to break off from their two-seat trainer, sending it into a roll.

Of the 508 military candidates who were considered, he was one of 110 test pilots whose credentials had earned them an invitation to learn more about the U.S. space program in general and its Project Mercury.

[21][22] Grissom passed the initial screening in Washington, D.C., and was among the thirty-nine candidates sent to the Lovelace Clinic in Albuquerque, New Mexico, and the Aeromedical Laboratory of the Wright Air Development Center in Dayton, Ohio, to undergo extensive physical and psychological testing.

He was nearly disqualified when doctors discovered that he suffered from hay fever, but was permitted to continue after he argued that his allergies would not be a problem due to the absence of ragweed pollen in space.

Grissom and the six other men, after taking a leave of absence from their respective branches of the military service, reported to the Special Task Group at Langley Air Force Base in Virginia on April 27, 1959, to begin their astronaut training.

[19][22] After splashdown in the Atlantic Ocean, the Liberty Bell 7's emergency explosive bolts unexpectedly fired, blowing off the hatch and causing water to flood into the spacecraft.

While waiting for recovery helicopters from USS Randolph to pick him up, Grissom struggled to keep from drowning after his spacesuit began losing buoyancy due to an open air inlet.

Later, Guenter Wendt, pad leader for the early American crewed space launches, wrote that he believed a small cover over the external release actuator was accidentally lost sometime during the flight or splashdown.

Another possible explanation was that the hatch's T-handle may have been tugged by a stray parachute suspension line, or was perhaps damaged by the heat of re-entry, and after cooling upon splashdown it contracted and caught fire.

[25][32] It has also been suggested that a static electricity discharge during initial contact between the spacecraft and the rescue helicopter may have caused the hatch's explosive bolts to blow.

[33] Jim Lewis, the pilot of Grissom's rescue helicopter, told Smithsonian Magazine that closer inspection of film footage made him remember the day in better detail.

He recalled that "Reinhard must have cut the antenna a mere second or two before I got us in a position for him to attach our harness to the capsule lifting bale," indicating that the timing of the helicopter's approach aligned with the static discharge theory.

[35] The two-man flight on Gemini 3 with Grissom and John W. Young made three revolutions of the Earth and lasted for 4 hours, 52 minutes and 31 seconds.

[37] Grissom, the shortest of the original seven astronauts at five feet seven inches tall, worked very closely with the engineers and technicians from McDonnell Aircraft who built the Gemini spacecraft.

[38][39] During this time Grissom invented the multi-axis translation thruster controller used to push the Gemini and Apollo spacecraft in linear directions for rendezvous and docking.

Much to the agency's chagrin, CAPCOM Gordon Cooper gave Gemini 3 its sendoff on launch with the remark to Grissom and Young, "You're on your way, Molly Brown!"

[53] The pilots' deaths were attributed to lethal hazards in the early CSM design and conditions of the test, including a pressurized 100 percent oxygen prelaunch atmosphere, wiring and plumbing flaws, flammable materials used in the cockpit and in the astronauts' flight suits, and an inward-opening hatch that could not be opened quickly in an emergency and not at all with full internal pressure.

[70] His death forced the cancellation of a student project to design a flag to represent Grissom and their school, which would have flown on the mission.

The dismantled Launch Pad 34 at Cape Canaveral Air Force Station bears two memorial plaques to the crew of Apollo 1.

[85] The Grissom Memorial, a 44-foot (13 m) tall limestone monument representing the Redstone rocket and his Mercury space capsule was dedicated in downtown Mitchell, Indiana, in 1981.

[88] The Gus Grissom Stakes is a thoroughbred horse race run in Indiana each fall; originally held at Hoosier Park in Anderson, it was moved to Horseshoe Indianapolis in Shelbyville in 2014.

[104] The three-letter identifier of the VHF Omni Directional Radio Range (VOR) located at Grissom Air Reserve Base is GUS.

[105] An academic building was renamed Grissom Hall in 1968 at the former Chanute Air Force Base, Rantoul, Illinois, where Minuteman missile maintenance training was conducted.

[106][107] The Virgil I. Grissom Museum, dedicated in 1971 by Governor Edgar Whitcomb,[108] is located just inside the entrance to Spring Mill State Park in Mitchell, Indiana.