Mercury-Redstone 3, or Freedom 7, was the first United States human spaceflight, on May 5, 1961, piloted by astronautAlan Shepard. It was the first crewed flight of Project Mercury. The project had the ultimate objective of putting an astronaut into orbit around the Earth and returning him safely. Shepard's mission was a 15-minute suborbital flight with the primary objective of demonstrating his ability to withstand the high g-forces of launch and atmospheric re-entry.
Shepard named his space capsuleFreedom 7, setting a precedent for the remaining six Mercury astronauts naming their spacecraft and the format of their names, the number 7 later included in all the crewed Mercury spacecraft names to honor NASA's first group of seven astronauts. His spacecraft reached an altitude of 101.2 nautical miles (116.5 statute miles, 187.5 km) and traveled a downrange distance of 263.1 nautical miles (302.8 statute miles, 487.3km). It was the fourth Mercury flight launched with the Mercury-Redstone Launch Vehicle,[Note 1] from Cape Canaveral, Florida, close to the Atlantic Ocean.
During the flight, Shepard observed the Earth and tested the capsule's attitude control system, turning the capsule around to face its blunt heat shield forward for atmospheric re-entry. He also tested the retrorockets which would return later missions from orbit, though the capsule did not have enough energy to remain in orbit. After re-entry, the capsule landed by parachute on the North Atlantic Ocean off the Bahamas. Shepard and the capsule were picked up by helicopter and brought to U.S. Navy aircraft carrier USS Lake Champlain.
The mission was a technical success, though American pride in the accomplishment was dampened by the fact that just three weeks before, the Soviet Union had launched the first human in space, Yuri Gagarin, who completed one orbit on Vostok 1. In 2017 the first National Astronaut Day was held on May 5 to pay tribute to this first U.S. flight.
The spacecraft for MR-3, Mercury capsule #7, was delivered to Cape Canaveral on December 9, 1960. It had originally been expected that a mission could be launched soon after the spacecraft was available, but Capsule #7 turned out to require extensive development and testing work before it was deemed safe for flight. However, as it had been earmarked since the summer as the first crewed spacecraft, the decision was taken to delay the mission until this particular capsule was ready, with a tentative launch date of March 6, rather than use an alternative capsule.[2] The booster originally intended for the flight, Redstone #3,[3] had been delivered to the Cape in early December;[4] however, it was then used on the MR-1A test flight on December 19.[5] The replacement, Redstone #7, did not arrive at the Cape until late March; by this time, however, the mission had already been postponed to await the results of another test flight.[6]
In late 1960, there had been a growing number of concerns about the safety of the Redstone launch vehicle; the MR-2 test flight, carrying Ham the chimpanzee, had experienced technical problems during the launch, leading to the spacecraft flying too high, too far and too fast.[7] As a result, the mission was two minutes longer than planned, and the re-entry subjected Ham to 14.7g rather than the planned figure of approximately 12g. The splashdown point was sixty miles from the nearest recovery ship, and it was over two and a half hours before a helicopter could recover the capsule and its passenger – by which time it had almost sunk.[8] As a result, NASA was unwilling to launch the MR-3 mission without further development work; by late February, there were still seven major alterations they had made to the booster which required testing.[9] An additional testing flight was accordingly added to the schedule, MR-BD (for "Booster Development"; it was originally known as MR-2A). This would launch on March 28, pushing the MR-3 flight back a month to April 25.[10] The MR-BD flight was almost completely successful, ensuring that the crewed MR-3 flight could proceed without further significant delay.[11]
The pilot for MR-3 had been chosen several months in advance, in early January, by the head of the program, Robert R. Gilruth. He had selected Alan Shepard (Navy) as the primary pilot, with John Glenn (Marine) and Gus Grissom (Air Force) as his backups; the other members of the Mercury Seven continued to train for later missions. The three names were announced to the press on February 22 without any indication as to which of the three was expected to fly the mission.[12] Shepard's name was only announced publicly after the initial launch attempt had been canceled, as Gilruth wished to keep his options open in the event that last-minute personnel changes were required.[13] Glenn served as Shepard's backup on launch day,[14] with Grissom focusing on training for MR-4, the next suborbital mission.[15]
Naming
Captain Shepard dubbed his capsule "Freedom 7". Per Shepard, "Pilots have always named their planes. It's a tradition. It never occurred to me not to name the capsule." Shepard discussed the name with his wife, Louise, backup pilot John Glenn, and Robert R. Gilruth, and all liked it.
Contrary to popular belief, the "7" was not a reference to the seven original astronauts selected for Mercury but rather to the fact that Shepard's spacecraft was factory model no. 7. However, the other astronauts liked the symbolism, and each appended 7 to their spacecraft names as well. Thus, Shepard set a double precedent, both for naming the Mercury spacecraft at all, and for the common structure of their naming.[16]
Flight
The initial launch attempt, on May 2, was canceled due to weather problems two hours and 20 minutes before the launch time, with Shepard waiting in a hangar already suited and prepared. The flight was rescheduled for two days later, when it was delayed one more day due to inclement weather conditions, until 5 May, with an expected launch time of 7:20am. EST.[Note 2][17]
The countdown began at 8:30p.m. the previous night, with Shepard waking up and eating a breakfast of steak and eggs with toast, coffee, and orange juice (the steak and eggs breakfast would soon become a tradition for astronauts the morning of a launch). He entered the spacecraft at 5:15am. ET, just over two hours before the planned 7:20 launch time. At 7:05am, the launch was held for an hour to let cloud cover clear – good visibility would be essential for photographs of the Earth – and fix a power supply unit; shortly after the count restarted, another hold was called in order to reboot a computer at Goddard Space Flight Center. The count was eventually resumed, after slightly over two and a half hours of unplanned holds, and continued with no further faults.[18] All of the delays resulted in Shepard lying on his back in the capsule for almost three hours, by which point he complained to the blockhouse crew that he had a severe need to urinate (because the mission would last under 20 minutes, nobody had thought to equip the Mercury with a urine collection device). The crew told him that this was impossible as they would have to set the White Room back up and waste considerable amounts of time removing the Mercury's heavily bolted hatch. An irate Shepard then announced that if he could not get out for a bathroom trip, he would simply urinate in his suit. When the blockhouse protested that that would short out the medical electrodes on his body, he told them to simply turn the power off. They complied, and Shepard emptied his bladder. Because of the position he was sitting in, the urine pooled somewhat underneath his back and with oxygen flowing through the spacesuit, he was soon dried out, and the countdown resumed.[19]
Launch of MR-3 on May 5, 1961
Mercury-Redstone 3 finally lifted off at 9:34am. ET, watched by an estimated 45 million television viewers in the United States.[20] Shepard was subjected to a maximum acceleration of 6.3g just before the Redstone engine shut down, two minutes and 22 seconds after launch. Freedom 7's space-fixed velocity was 5,134 miles per hour (8,262km/h), close to the planned value. Upon shutdown of the booster, the escape tower was jettisoned. Ten seconds later came capsule separation: the capsule detonated the explosive bolts on the Marman clamping ring that joined it to the booster and fired its posigrade rockets to gain distance. After capsule separation, the automated attitude control system (the Automatic Stabilization Control System, or ASCS) damped out any residual tumbling motions and then yawed Freedom 7 around 180 degrees, so the retrorockets would face forward ready for firing.[21]
Shepard now began testing manual control of the spacecraft's orientation. For redundancy purposes, the Mercury spacecraft's manual attitude control system used a different set of control jets than the automatic system and had its own fuel supply; when the system was activated, moving the three-axis control stick proportionally opened valves to the manual jets. The system could be selectively enabled on each axis, with ASCS automatically controlling the non-enabled axes. Shepard gradually assumed manual control, one axis at a time, leaving the remaining axes to ASCS. First he took manual control of pitch, reorienting the spacecraft from its "orbit attitude" of 14 degrees nose-down pitch to the retrofire attitude of 34 degrees nose-down pitch, then returning to orbit attitude. He then took manual control of yaw along with pitch, yawing the spacecraft to the left and then to the right to bring it back in line. Finally he assumed control of roll as well, testing it and then restoring the spacecraft's roll to normal. Once Shepard had taken control of all three axes, he found that the spacecraft's manual response was about the same as that of the Mercury simulator; however, he could not hear the jets firing, as he could on the ground, due to the levels of background noise.[22][23][24]
Shepard's next task was to make observations of the ground from the spacecraft's periscope, which extended through the "bottom" of the hull beneath his feet. Shepard's craft, an earlier version of the Mercury capsule, also had two small round viewing windows, one on each side, but the periscope was its primary means for observing. The periscope could be set either to a low-magnification wide-angle view or to a high-magnification narrow-angle view, and different optical filters could be inserted by turning a knob. During his long wait on the launch pad, Shepard had inserted a medium-gray filter in the periscope to cut down on sun glare, but he had not had time to undo this before launch. He found that when he tried to reach the filter knob to change it, the wrist of his spacesuit would bump the handle by his left hand that would manually activate the launch escape system. Even though the escape tower was long gone, Shepard gave up on trying to change the filter out of caution, leaving it in for the rest of the flight. Although the gray filter washed out colors, Shepard was still easily able to distinguish major land masses from clouds. He reported identifying major features such as the east coast of Florida, Lake Okeechobee, and Andros Island, the largest island of the Bahamas, but cloud cover made it difficult for him to make out other Bahamian islands.[25][26]
With the spacecraft still under manual control, but now using the periscope rather than the panel instruments for his attitude reference, Shepard had maintained his roll and yaw attitude, but he had inadvertently let the spacecraft drift in pitch. As the spacecraft approached the highest point of its suborbital arc, the "start retro sequence" light came on, alerting Shepard that the three retrorockets were about to fire. They would do this in sequence five seconds apart, burning for ten seconds each. Shepard began adjusting his pitch nose downward toward the proper retrofire attitude of –34 degrees, but he only got to around orbit attitude (–14 degrees) before the first retrorocket fired. He then got his pitch further down to about –25 degrees in time for the second and third retrorockets. This pitch discrepancy was not critical for this flight, because Shepard's suborbital trajectory would lead to reentry anyway, and the difference in pitch wouldn't affect Shepard's landing location much; Shepard was only testing the pilot's ability to manually control the spacecraft's attitude during retrofire. In his initial postflight debriefing, Shepard reported that he must have somehow gotten confused about his pitch attitude, but as it turned out he was the victim of a misunderstanding. This particular spacecraft's pitch indicator had originally been set so that its reference position for retrofire attitude, which was the "nine o'clock" position on the indicator, was at –43 degrees pitch, rather than the –34 degrees later decided upon for retrofire. Shepard had assumed it was still set that way and deliberately adjusted his pitch high to compensate. But in fact the indicator had been changed, with the "nine o'clock" reference position being updated to the correct –34 degrees. Somehow Shepard had not been informed, so his compensation made his pitch too high.[27]
Just after retrofire, Shepard switched into the "fly-by-wire" control mode, where the pilot's motions of the three-axis control stick electrically triggered the control jets of the automatic system to fire for the desired positioning, rather than proportionally opening the manual system's control jets. Soon afterward, the retrorocket pack was automatically jettisoned. This pack was attached over the heatshield by straps and so was normally released before reentry. Shepard heard the noise of the jettison and saw one of the straps fly past a window, but the confirmation light did not turn on. However, fellow Mercury astronaut Deke Slayton, who was acting as capsule communicator ("CAPCOM") in the Mercury Control Center, confirmed to Shepard that the pack had jettisoned, so Shepard activated the manual override for the jettison system to trigger the light.[28][29][30] It was later determined that the retro-jettison light hadn't activated because of an issue with the electrically triggered pyrotechnic "squibs" that were fired to release the retrorocket pack. These squibs, when triggered, could draw excessive current from the electrical system, dropping its voltage to the point that the timer which was supposed to activate the retro-jettison light got reset. The squibs were modified to prevent this problem in future missions.[31]
Shepard reported that fly-by-wire felt smooth and gave the sensation of being fully in command of the craft,[32] before letting the automatic systems briefly take over to reorient the capsule for reentry. He then kept control until the g-forces peaked at 11.6g during re-entry; he held the capsule until it had stabilized and then relinquished control to the automated system. The descent was faster than anticipated, but the parachutes deployed as planned, a drogue at 21,000ft (6.4km) and a main parachute at 10,000ft (3.0km).[25][33]
Splashdown occurred with an impact comparable to landing a jet aircraft on an aircraft carrier. Freedom 7 tilted over on its right side about 60 degrees from an upright position, but did not show any signs of leaking; it gently righted itself after a minute, and Shepard was able to report to the circling aircraft that he had landed safely and was ready to be recovered. A recovery helicopter arrived after a few minutes, and after a brief problem with the spacecraft antenna, the capsule was lifted partly out of the water in order to allow Shepard to leave by the main hatch. He squeezed out of the door and into a sling hoist, and was pulled into the helicopter, which flew both the astronaut and his spacecraft to a waiting aircraft carrier, USSLake Champlain. The whole recovery process had taken only eleven minutes, from splashdown to arriving aboard.[34]
The flight lasted 15 minutes, 22 seconds and the spacecraft traveled 302 miles (486km) from its launch point, ascending to 116.5 miles (187.5km). Freedom 7 landed at these coordinates: 27°14′N75°53′W / 27.23°N 75.88°W / 27.23; -75.88. It reached a speed of 5,180mph (8,340km/h).[35] Besides that, the spaceflight mission featured the first manual pilot control of the spacecraft.[36]
Following the flight the spacecraft was examined by engineers and found to be in excellent shape, so much so that they decided it could have been safely used again in another launch. Given to the Smithsonian Institution by NASA, Freedom 7 was previously displayed at the U.S. Naval Academy in Annapolis, Maryland until 2012. In 2012, it was on display at the John F. Kennedy Library in Boston, Massachusetts. Beginning on May 5, 2021, the 60th Anniversary of the First American in Space, the Mercury-Redstone (MR-3) spacecraft Freedom 7 was on display and exhibited at the Smithsonian's Steven F. Udvar-Hazy Center located in Chantilly, Virginia. It currently is on display at the Smithsonian's National Air and Space Museum located in Washington, D.C.
President Kennedy watching the flight on TV together with the First Lady, Vice President Johnson and others
Alan Shepard in Freedom 7 spacecraft before launch
Photo taken by 70mm Earth-Sky Camera mounted on the spacecraft
Alan Shepard on the deck of the aircraft carrier USS Lake Champlain after recovery of Freedom 7
Freedom 7 formerly on display at the U.S. Naval Academy (now displayed at the Smithsonian's National Air and Space Museum in Washington, D.C.)
Commemorative patch
Depiction in popular culture
In June 1961, Laurie Records issued a 45 rpm single featuring William Allen and Orchestra entitled "Space Flight Freedom 7". It consisted of recreations of the tower to astronaut communications spoken over an instrumental backing.
In the 2008 video game Fallout 3, the player can visit the Museum of Technology in the ruins of Washington D.C., two centuries after a nuclear war. The game takes place in an alternate timeline that diverges from reality after World War II. In the museum is an exhibit about a slightly different version of Mercury-Redstone 3/Freedom 7 called Defiance 7 that launched on May 5, 1961 (the day Freedom 7 was launched) and was piloted by fictional astronaut Carl Bell. The exhibit states that Bell was the first human in space in this timeline and did not survive the space flight, having died in a crash landing. His skeleton and space suit were donated to the museum and are on display there.[37]
Flight events
Flights events of the Mercury-Redstone 3 mission[38]:8
Project Mercury was the first human spaceflight program of the United States, running from 1958 through 1963. An early highlight of the Space Race, its goal was to put a man into Earth orbit and return him safely, ideally before the Soviet Union. Taken over from the US Air Force by the newly created civilian space agency NASA, it conducted 20 uncrewed developmental flights, and six successful flights by astronauts. The program, which took its name from Roman mythology, cost $2.68 billion. The astronauts were collectively known as the "Mercury Seven", and each spacecraft was given a name ending with a "7" by its pilot.
Ham, a chimpanzee also known as Ham the Chimp and Ham the Astrochimp, was the first great ape launched into space. On January 31, 1961, Ham flew a suborbital flight on the Mercury-Redstone 2 mission, part of the U.S. space program's Project Mercury.
Mercury-Redstone 4 was the second United States human spaceflight, on July 21, 1961. The suborbital Project Mercury flight was launched with a Mercury-Redstone Launch Vehicle, MRLV-8. The spacecraft, Mercury capsule #11, was nicknamed Liberty Bell 7. It was piloted by astronaut Virgil "Gus" Grissom.
Mercury-Atlas 6 (MA-6) was the first crewed American orbital spaceflight, which took place on February 20, 1962. Piloted by astronaut John Glenn and operated by NASA as part of Project Mercury, it was the fifth human spaceflight, preceded by Soviet orbital flights Vostok 1 and 2 and American sub-orbital flights Mercury-Redstone 3 and 4.
Mercury-Atlas 7, launched May 24, 1962, was the fourth crewed flight of Project Mercury. The spacecraft, named Aurora 7, was piloted by astronaut Scott Carpenter. He was the sixth human to fly in space. The mission used Mercury spacecraft No. 18 and Atlas launch vehicle No. 107-D.
Mercury-Atlas 8 (MA-8) was the fifth United States crewed space mission, part of NASA's Mercury program. Astronaut Walter M. Schirra Jr., orbited the Earth six times in the Sigma 7 spacecraft on October 3, 1962, in a nine-hour flight focused mainly on technical evaluation rather than on scientific experimentation. This was the longest U.S. crewed orbital flight yet achieved in the Space Race, though well behind the several-day record set by the Soviet Vostok 3 earlier in the year. It confirmed the Mercury spacecraft's durability ahead of the one-day Mercury-Atlas 9 mission that followed in 1963.
Mercury-Atlas 9 was the final crewed space mission of the U.S. Mercury program, launched on May 15, 1963, from Launch Complex 14 at Cape Canaveral, Florida. The spacecraft, named Faith 7, completed 22 Earth orbits before splashing down in the Pacific Ocean, piloted by astronaut Gordon Cooper, then a United States Air Force major. The Atlas rocket was No. 130-D, and the Mercury spacecraft was No. 20. As of January 2024, this mission marks the last time an American was launched alone to conduct an entirely solo orbital mission.
Malcolm Scott Carpenter was an American naval officer and aviator, test pilot, aeronautical engineer, astronaut, and aquanaut. He was one of the Mercury Seven astronauts selected for NASA's Project Mercury in April 1959. Carpenter was the second American to orbit the Earth and the fourth American in space, after Alan Shepard, Gus Grissom, and Glenn.
Mercury-Atlas 5 was an American spaceflight of the Mercury program. It was launched on November 29, 1961, with Enos, a chimpanzee, aboard. The craft orbited the Earth twice and splashed down about 200 miles (320 km) south of Bermuda, and Enos became the first primate from the United States and the third great ape to orbit the Earth.
Mercury-Atlas 10 (MA-10) was a cancelled early crewed space mission, which would have been the last flight in NASA's Mercury program. It was planned as a three-day extended mission, to launch in late 1963; the spacecraft, Freedom 7-II, would have been flown by Alan Shepard, a veteran of the suborbital Mercury-Redstone 3 mission in 1961. However, it was cancelled after the success of the one-day Mercury-Atlas 9 mission in May 1963, to allow NASA to focus its efforts on the more advanced two-man Gemini program.
Mercury-Atlas 1 (MA-1) was the first attempt to launch a Mercury capsule and occurred on July 29, 1960 at Cape Canaveral, Florida. The spacecraft was unmanned and carried no launch escape system. The Atlas rocket suffered a structural failure 58 seconds after launch at an altitude of approximately 30,000 feet (9.1 km) and 11,000 feet (3.4 km) down range. All telemetry signals suddenly ceased as the vehicle was passing through Max Q. Because the day was rainy and overcast, the booster was out of sight from 26 seconds after launch, and it was impossible to see what happened.
Mercury-Redstone 1 (MR-1) was the first Mercury-Redstone uncrewed flight test in Project Mercury and the first attempt to launch a Mercury spacecraft with the Mercury-Redstone Launch Vehicle. Intended to be an uncrewed sub-orbital spaceflight, it was launched on November 21, 1960 from Cape Canaveral Air Force Station, Florida. The launch failed in an abnormal fashion: immediately after the Mercury-Redstone rocket started to move, it shut itself down and settled back on the pad, after which the capsule jettisoned its escape rocket and deployed its recovery parachutes. The failure has been referred to as the "four-inch flight", for the approximate distance traveled by the launch vehicle.
Mercury-Redstone 1A (MR-1A) was launched on December 19, 1960 from LC-5 at Cape Canaveral, Florida. The mission objectives of this uncrewed suborbital flight were to qualify the spacecraft for space flight and qualify the system for an upcoming primate suborbital flight. The spacecraft tested its instrumentation, posigrade rockets, retrorockets and recovery system. The mission was completely successful. The Mercury capsule reached an altitude of 130 miles (210 km) and a range of 235 miles (378 km). The launch vehicle reached a slightly higher velocity than expected - 4,909 miles per hour (7,900 km/h). The Mercury spacecraft was recovered from the Atlantic Ocean by recovery helicopters about 15 minutes after landing. Serial numbers: Mercury Spacecraft #2 was reflown on MR-1A, together with the escape tower from Capsule #8 and the antenna fairing from Capsule #10. Redstone MRLV-3 was used. The flight time was 15 minutes and 45 seconds.
Mercury-Redstone 2 (MR-2) was the test flight of the Mercury-Redstone Launch Vehicle just prior to the first crewed American space mission in Project Mercury. Carrying a chimpanzee named Ham on a suborbital flight, Mercury spacecraft Number 5 was launched at 16:55 UTC on January 31, 1961, from LC-5 at Cape Canaveral, Florida. The capsule and Ham, the first great ape in space, landed safely in the Atlantic Ocean 16 minutes and 39 seconds after launch.
Mercury-Redstone BD was an uncrewed booster development flight in the U.S. Mercury program. It was launched on March 24, 1961, from Launch Complex 5 at Cape Canaveral, Florida. The mission used a boilerplate Mercury spacecraft and Redstone MRLV-5.
Mercury-Atlas 4 (MA-4) was an uncrewed test flight within NASA's Project Mercury program, launched on September 13, 1961, at 14:04:16 UTC from Cape Canaveral Air Force Station Launch Complex 14. The mission's primary purpose was to evaluate the Mercury spacecraft's performance in orbit and to test the Mercury Space Flight Network. Despite initial technical challenges, Mercury-Atlas 4 successfully met its goals. The mission involved testing the Mercury spacecraft, specifically Mercury #8A, which completed one orbit around Earth. This successful flight provided important data and insights for NASA's Project Mercury, supporting the planning and development of upcoming crewed missions in the program.
Project Gemini was the second United States human spaceflight program to fly. Conducted after the first American manned space program, Project Mercury, while the Apollo program was still in early development, Gemini was conceived in 1961 and concluded in 1966. The Gemini spacecraft carried a two-astronaut crew. Ten Gemini crews and 16 individual astronauts flew low Earth orbit (LEO) missions during 1965 and 1966.
A space capsule is a spacecraft designed to transport cargo, scientific experiments, and/or astronauts to and from space. Capsules are distinguished from other spacecraft by the ability to survive reentry and return a payload to the Earth's surface from orbit or sub-orbit, and are distinguished from other types of recoverable spacecraft by their blunt shape, not having wings and often containing little fuel other than what is necessary for a safe return. Capsule-based crewed spacecraft such as Soyuz or Orion are often supported by a service or adapter module, and sometimes augmented with an extra module for extended space operations. Capsules make up the majority of crewed spacecraft designs, although one crewed spaceplane, the Space Shuttle, has flown in orbit.
The Mercury-Redstone Launch Vehicle, designed for NASA's Project Mercury, was the first American crewed space booster. It was used for six sub-orbital Mercury flights from 1960–1961; culminating with the launch of the first, and 11 weeks later, the second American in space. The four subsequent Mercury human spaceflights used the more powerful Atlas booster to enter low Earth orbit.
Gemini SC-2 was the second NASA Project Gemini full-up reentry capsule built. This McDonnell Gemini capsule was the first space capsule to be reused, flying twice in suborbital flights. SC-2 flew on Gemini 2 and OPS 0855 flights. The capsule is currently on display at the Air Force Space and Missile Museum at Cape Canaveral Air Force Station.
References
Notes
↑ The previous three Mercury-Redstone flights were the uncrewed Mercury-Redstone 1A, Mercury-Redstone 2 (which carried a chimpanzee), and Mercury-Redstone BD, an uncrewed flight with a "boilerplate" (non-production) Mercury capsule.
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