Mercury-Atlas 8
Encyclopedia
Mercury-Atlas 8 was an early manned 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 American
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.
Planning began for the third orbital mission in February 1962, aiming for a six-or-seven-orbit flight to build on the previous three-orbit missions. NASA officially announced the mission to the public on June 27, and the flight plan was finalised in late July. The mission focused on engineering tests rather than on scientific experimentation. The mission finally launched on the morning of October 3, having been delayed two weeks because of problems with the Atlas booster
. A series of minor booster problems during launch and a faulty temperature controller in Schirra's pressure suit
were the only technical problems noted during the flight. The spacecraft orbited in both automated and passive flight modes for prolonged periods while the pilot monitored it and carried out some minor scientific experiments. After six orbits, the capsule landed in the Pacific Ocean half a mile from the recovery carrier
, and was hoisted aboard for Schirra to disembark.
The scientific results of the mission were mixed. The astronaut returned healthy and was released after nine hours of confinement in a low-gravity environment. Observation of the Earth's surface proved unproductive, however, because of heavy cloud cover and bad photographic exposures. The public and political reaction was muted compared with that of earlier missions, as the Cuban Missile Crisis
quickly eclipsed the space race
in the news. The mission was a technical success: all the engineering objectives had been completed without significant malfunctions, and the spacecraft had used even less fuel than expected. This confirmed the capabilities of the Mercury spacecraft and allowed NASA to plan with confidence for a day-long flight, MA-9
, which had been an early goal of the Mercury program.
". There was a widespread perception, however, that the United States was falling behind; its two missions had been suborbital and had lasted only a few minutes. The Soviet missions had both orbited the Earth, and the second, Vostok 2
, had remained in orbit for a full day. Using the new high-powered Atlas booster
, the coming orbital Mercury missions were expected to shorten the gap between the two countries.
NASA announced the first two orbital missions at the end of November 1961, shortly after the Mercury-Atlas 5
(MA-5) test flight, which had carried a chimpanzee
and twice orbited the Earth. MA-6
was planned as the first orbital flight, with John Glenn
as the primary crew and Scott Carpenter
as his backup. The follow-up mission, MA-7
was to be crewed by Deke Slayton
, with Wally Schirra
as his backup. In February 1962, the first draft planning began for MA-8, the third orbital mission, with a goal of "six or seven" orbits, as an intermediate step towards a day-long 18-orbit flight. The decision to move to six orbits rather than seven was driven by the mission rules on contingency recovery operations; a seventh orbit would have required significant additional recovery forces to be able to reach the capsule anywhere on its trajectory within eighteen hours. The six-orbit profile had other effects on the recovery plans; the optimum recovery point was moved to the Pacific Ocean, rather than the Atlantic.
On March 15, 1962, NASA announced that Slayton was medically unfit and would be replaced by Scott Carpenter
as the prime crew for the MA-7 mission. The decision to replace him with Carpenter, rather than his official backup Schirra, was justified by the large amount of training Carpenter had managed while preparing for the long-delayed MA-6 mission. After the success of the MA-6 and MA-7 missions, both of three orbits, pressure began to mount to fly an extended mission. On June 27, 1962, NASA first announced its plan for the upcoming MA-8 mission, which would last for "as many as six" orbits. Schirra was named as the prime crew for MA-8, with Gordon Cooper
as his backup, repeating the backup-one fly-one pattern set by the previous two missions. The pattern would be repeated for MA-9
, flown by Cooper, and the planned but cancelled MA-10
, which would have been flown by Cooper's backup, Alan Shepard
.
The Soviet Union had not flown any further flights by the time MA-7 landed, putting both sides of the space race
even at two orbital flights each. While the Soviets had flown for longer, the Mercury program was gaining momentum, with a six-orbit mission currently planned and press speculation about a one-day mission. However, in mid-August, the Soviet Union launched two orbital missions, Vostok 3
and Vostok 4
, within a day of each other. The two craft were in intersecting orbits, but despite much speculation did not attempt to rendezvous; they completed missions of 64 and 48 orbits respectively, just under four and three days, landing within a few minutes of each other on August 15. This was far ahead of anything currently planned for Mercury, and NASA quickly considered the prospect of modifying a capsule to have an active manoeuvring and rendezvous capability, using technology being developed for the Gemini program. However, after examining the time and safety implications of this proposal, it was decided to abandon the idea and continue with the planned six-orbit mission.
as appropriate for an "engineering evaluation", and the "7" to refer to the seven Mercury astronauts
.
The mission objectives involved evaluating the performance of the spacecraft over six orbits, as well as the effect of prolonged microgravity on the pilot. The specific spacecraft systems would also be evaluated and tested, and the worldwide tracking and communications network would be tested to see how well it would stand up in an extended mission. The flight control experiments included manually turning the spacecraft around, yaw and pitch
manoeuvres to determine how easy it was to control the spacecraft attitude, realignment of the onboard gyroscopes in flight, and leaving the spacecraft to drift on-orbit.
Four non-engineering scientific experiments were planned, two requiring the active involvement of the astronaut and two completely passive. The first involved the astronaut watching for four high-powered flares while passing over Woomera, Australia, and for a xenon arc lamp
while passing over Durban, South Africa. The second involved two sets of photographs to be taken using a 70mm Hasselblad camera as well as conventional color photographs of the Earth from orbit. Focusing on geological features and cloud patterns, photographs were to be taken through a set of colored filters provided by the U. S. Weather Bureau. The latter were intended to help calibrate the spectral reflectivity of clouds and surface features, which in turn would help improve the cameras on future weather satellites. The passive experimentation packages were two sets of radiation-sensitive photographic films, from the Goddard Space Flight Center
and the U. S. Navy School of Aviation Medicine, and a set of eight different experimental ablative materials attached to the outside of the spacecraft to test their performance during re-entry.
motors, to save weight, and a SOFAR bomb
was added. This would be ejected at the time the main parachute was deployed, and would help recovery crews find the spacecraft after it landed. A number of modifications were made to the reaction control system
, and the communications equipment was upgraded.
The Atlas booster had been modified since the previous flight, and now included a modified fuel injector and a new hypergolic fuel igniter instead of the original pyrotechnic igniter.
on January 16, 1962. The Atlas LV-3B
booster assigned to the mission, number 113-D, was accepted by NASA at the Convair plant on July 27 and delivered on August 8. In late July, the launch date was set for September 18, but delays with the Atlas booster's delivery and a series of technical concerns with the safety of the rocket motors caused it to be pushed back several weeks. On September 6, the tests were scheduled to continue until September 24, which allowed for a probable launch on October 3. The booster was test-fired on September 8 to test changes to the engine combustion, and reported as ready for assembly on September 18.
Concerns had been raised that the radiation belt produced in orbit by the recent Operation Dominic nuclear tests would be dangerous to manned space missions, but an extensive study announced in early September declared that it was safe to fly. While the outside of the capsule was expected to receive a dosage of around 500 röntgens, the study concluded that shielding and the effect of the spacecraft structure would reduce this to around 8 röntgens experienced by the astronaut, well within established tolerance limits.
Schirra began training for the mission in early July, logging 29 hours in simulators as well as 31 hours in the spacecraft itself. This included multiple systems tests and three simulated flights, culminating in a six-and-a-half-hour simulated flight on September 29, with the spacecraft and booster fully stacked on the pad. Highlights of the training period included a visit from President John F. Kennedy
on September 11.
The mission was reported as ready to go—"except for the weather"—on October 1. The major concern with the weather was a major tropical storm in the Atlantic
, though there were also worries over a series of typhoons in the Pacific which could pose a problem for recovery operations. On the evening of October 2, the decision was taken to launch the next morning.
he had speared
the day before—and a brief physical he left for the launchpad at around 4 am. He entered the spacecraft at 4:41, where he found a steak sandwich left for him in the 'glove compartment', and began the pre-launch checks. The launch countdown proceeded as planned until 6:15, when there was a 15-minute hold to allow the Canary Islands
tracking station to repair a radar set. The countdown resumed at 6:30 and proceeded to booster ignition with no further delays. The launch itself began nominally, but after 10 seconds the booster began to roll clockwise, threatening a possible abort. However, after a few tense moments, the roll stopped as suddenly as it had begun. This was later identified as being due to a slight misalignment of the main engines and was kept under control by the booster's vernier thrusters.
Around three and a half minutes into the flight, Deke Slayton
, the capsule communicator, cut in to ask Schirra "Are you a turtle today?" Schirra, nonplussed, announced that he was switching to the on-board voice recorder (rather than the broadcast radio circuit) to leave his answer; the mission communications transcript noted this as "[correct answer recorded]". The "turtle club
" was a recurrent joke among the astronaut corps; on being challenged with this question, the correct response was "you bet your sweet ass I am", with a failure to give the password being punishable by buying a round of drinks. Schirra noted later that he "wasn't ready for all the world to hear it", and chose to use the on-board recorder to avoid saying the answer over the air.
The booster engines cut off 2 seconds earlier than planned, but the sustainer engine burned for about 10 seconds longer than intended, giving an extra 15 feet per second (4.6 m/s) of velocity and putting the spacecraft in a slightly higher orbit than planned. Initial analysis of the trajectory confirmed that the capsule could remain in a stable orbit for at least seven orbits, ensuring there would be no need for an early de-orbit.
After separating from the Atlas booster, Schirra stabilized the spacecraft and slowly cartwheeled into the correct attitude; he deliberately kept the motion slow to conserve fuel, and was able to position the capsule using half a percent of his fuel reserves. He briefly tracked the spent booster, which was rotating slowly past, but made no attempt to move towards it. As the spacecraft moved across the Atlantic, he turned his attention to testing manual control of the spacecraft, which he found sloppy compared to the fly-by-wire system.
Crossing over the eastern coast of Africa, he began to feel overheated; this problem was also apparent to the ground controllers, who were having a debate with the flight surgeon over whether it was safe to continue or if the mission should be ended after the first orbit. The flight director, Christopher Kraft
, followed the surgeon's advice to see if the problem would settle, and gave the go for a second orbit. Schirra eventually stabilized the problem over time, slowly dialling the suit's control knob to a high cooling setting; he compared the heat to that of "mowing a lawn in Texas".
Over Australia, Schirra watched for a flare launched from the ground, but it was occluded by clouds; he, was however, able to see lightning and the lit outline of Brisbane
. Through the night pass over the Pacific, he tested the capsule's on-board periscope, though he found it difficult to use and quickly covered it up as soon as the sun rose. Crossing over Mexico, he reported that he was in "chimp configuration", with the capsule running entirely on automatic without any input from the pilot, and as he began his second orbit began testing a yaw manoeuvre using the Earth through the main window as a reference, rather than via the much-maligned periscope.
On the second orbit, he confirmed the existence of Glenn's "fireflies", the shower of small bright particles first reported on MA-6
, and during the night section practiced yaw manoeuvres using first the Moon and then known stars as reference points. The second proved difficult to work with, as the small windows of the Mercury capsule gave a very limited field of view, making it hard to identify constellations. Travelling across the Pacific, he again fell back into automatic flight, chatting with Gus Grissom
at the Hawaiian tracking station about the qualities of the manual control system.
As he began the third orbit, Schirra disconnected the spacecraft's gyroscopes, turned off part of the electrical power system, and let the capsule drift. He took advantage of this quiet period to test his spatial awareness and motor control, which he found was broadly unaffected by weightlessness
, and to eat a light meal. He powered the spacecraft back up over the Indian Ocean, and continued over the Pacific. At Hawaii, he was given clearance for a full six-orbit mission, and as he crossed over towards California shut down the electrical power for a second period of drifting flight, during which he occupied himself taking photographs with the onboard camera.
On the fourth orbit, drifting in an inverted spacecraft with the Earth 'above' him, Schirra continued his photography and attempted—unsuccessfully—to spot the Echo 1 satellite while passing over East Africa. As he approached California, he spoke briefly to John Glenn
in a two-minute conversation broadcast live across the United States on radio and television. Problems began to recur with the pressure suit, with water condensing on the faceplate; Schirra, concerned about the internal temperature, avoided opening the visor to clean it for fear that the suit temperature would misbehave again.
By the fifth orbit, Schirra had begun to relax, commenting that it was the first rest he had had since December 1961. He used a small bungee cord
exercise device for "a little bit of stretching", before dropping into manual attitude control, where he reported a sudden burst of oversteering and high fuel use. Over the Atlantic he returned to observation and photography; he failed to spot the planned high-power light near Durban
, in South Africa, due to cloud cover, but did make out the brightly lit city of Port Elizabeth. Over the Philippines, he reported on his fuel status; after four and a half of the planned six orbits, he still had eighty percent remaining in both manual and automatic fuel tanks. Passing over Quito, Ecuador, towards the end of his fifth orbit, Schirra was asked by the tracking station if he had any message to pass on "in Spanish to the fellows down here", and he made some comments on how beautiful the country appeared from orbit, ending with a cheery "Buenos Dias, y'all!" Schirra later noted that he was "furious" at this point—he was preparing for re-entry and didn't want to be distracted with making public statements.
The sixth orbit was dominated by preparations for re-entry, though Schirra was able to take a last set of photographs of South America and try another set of spatial-orientation tests. He armed the retrorocket
s passing over the western Pacific, and fired the first one at 8:52 mission elapsed time
. The automatic control system held the capsule "steady as a rock" during this period, though after the retrorockets had stopped firing Schirra noted that the system had burned almost a quarter of its fuel in the process.
As the spacecraft continued towards re-entry
after the de-orbit burn, Schirra used the high-power thrusters to put the capsule in the correct orientation, noting that the attitude control felt "sloppy". He then enabled the rate stabilization control system, an automatic control method which used up fuel at a very high rate, to maintain control during re-entry; this was a specific engineering request, and it dismayed Schirra to see the fuel he had husbanded for six orbits be used so quickly.
The local recovery group in the prime target area, in the central Pacific, consisted of an aircraft carrier, the USS Kearsarge
, in the centre of the landing area, with three destroyers strung out along the orbital path. Four search aircraft were also assigned to the area, and three recovery helicopters were based aboard the Kearsarge.
The Kearsarge picked up the capsule on radar while still 200 miles (321.9 km) from landing; 90 miles (144.8 km) further up the landing path, the destroyer USS Renshaw
reported a sonic boom as it passed overhead. At 40000 feet (12,192 m), Schirra deployed the drogue parachute
, and then the main parachute at 15000 feet (4,572 m). The landing was surprisingly precise, 4.5 miles (7.2 km) from the target point and 0.5 mile (0.80467 km) from the Kearsarge, and Schirra joked that he was on course for the recovery carrier's "number three elevator". The capsule hit the water, sank and bobbed to the surface again, righting itself after about 30 seconds. Three pararescue swimmers were dropped by one of the helicopters to help him climb out, but Schirra radioed that he would prefer to be towed to the carrier, and a whaleboat
from the Kearsarge was sent with a line.
Forty minutes after landing, Sigma 7 was hoisted aboard the Kearsarge; five minutes later, Schirra blew the explosive hatch and climbed out to a waiting crowd. After doing this, examinations showed clear bruising on his hand from operating the heavy ejector switch, which he felt provided an important vindication for fellow pilot Gus Grissom
's hatch expulsion accident during the Liberty Bell 7 mission. Grissom had maintained that the hatch blew without his input; the fact that he had no bruising was seen as evidence that he had not blown the hatch early and sunk his capsule, but that it was a mechanical malfunction.
Schirra remained aboard for three days of medical tests and debriefing before disembarking, while the spacecraft was offloaded at Midway Island and transferred to an aircraft for further transport. It was returned to Cape Canaveral for analysis, with the long-term intention of putting it on permanent display.
The spent Atlas booster re-entered the atmosphere on October 4, the day after the launch, and was burned up. After a period on display at the Johnson Space Center, the capsule is currently displayed at the United States Astronaut Hall of Fame
, Titusville, Florida
.
Scientifically, the light-observation experiments were unsuccessful, as both target locations were covered by thick cloud cover. However, Schirra was able to view lightning near Woomera, and noted the lights of a city a few hundred miles from Durban. The filtered photography for the Weather Bureau worked as planned, with 15 photographs taken; the conventional color photography was less successful, with several of the 14 photographs unusable due to overexposure or excess cloud cover. In the end, the conventional photographs were not used for scientific examination due to these problems. Schirra noted that the sheer amount of cloud coverage, worldwide, could provide problems for future activity of this kind; however, Africa, and the south-western United States, were perfectly clear.
Schirra's post-flight report noted the "fireflies" seen on the previous two missions, and emphasized the remarkable visual effect of the thick band of the atmosphere visible around the horizon. However, he was unimpressed with the view of Earth from space; the amount of detail he could make out compared well with that from high-flying aircraft, and he told debriefers that it was "nothing new" compared to flight at 50000 feet (15,240 m). Overall, he concluded that Sigma 7 was on "the top of the list" of aircraft he had flown, displacing the F8F Bearcat
, a naval piston-engined fighter, while the mission itself had been "textbook".
Schirra gave a public lecture at Rice University
after returning to Houston, where he received a motorcade through the city. However, the Cuban Missile Crisis
had been steadily escalating through September, and helped drive discussion of Schirra's successful flight down the news schedules; public concern about the relative effectiveness of Soviet and American space launchers was displaced by a more pressing concern over Soviet military rockets. He visited Washington, DC, to receive the NASA Distinguished Service Medal
from President Kennedy on October 16, the same day Kennedy had first seen U-2 photographs of missile sites in Cuba; the meeting was friendly and informal despite the circumstances. Robert Kennedy, Schirra later noted, took him aside and sounded him out about a potential political career, the same way he had sounded out John Glenn
a year earlier. Unlike Glenn, however, Schirra politely turned the suggestion down, and chose to remain with NASA. His later career saw him commanding the backup crew for the first Gemini mission, then the prime crew for the 1965 Gemini 6A
mission, where he flew the first active rendezvous between two spacecraft - earlier plans for it to conduct the first on-orbit docking had been cancelled - and finally commanding the first Apollo mission, Apollo 7
, in 1968. He eventually resigned from NASA in the summer of 1969.
The success of MA-8 made the preparation for MA-9
"considerably easier", though it did cause some observers to suggest the program should be ended abruptly in order to conclude on a clear note of success, rather than risking another—potentially catastrophic—flight. However, this was not a view shared by the NASA planners, who had been pressing for a one-day Mercury mission since mid-1961, when it first began to seem technically feasible. To prepare the spacecraft for a long-duration mission involved trimming as much on-board weight as possible to offset the additional consumables required. The changes made to the capsule hardware on MA-8 were now used to justify the removal of 12 pounds (5.4 kg) of control equipment and 5 pounds (2.3 kg) of radio equipment, as well as the 76 pounds (34.5 kg) periscope which Schirra had found so unhelpful. In total, there were 183 alterations listed between the capsules for the MA-8 and MA-9 missions. The spacecraft was to be equipped with several cameras, building on Schirra's photographic work, though weight and power limitations did restrict the amount of scientific experiments that could be scheduled.
NASA
The National Aeronautics and Space Administration is the agency of the United States government that is responsible for the nation's civilian space program and for aeronautics and aerospace research...
Mercury program
Mercury program
Mercury Program might refer to:*the first successful American manned spaceflight program, Project Mercury*an American post-rock band, The 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 American
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
orbital flight yet achieved in the Space Race
Space Race
The Space Race was a mid-to-late 20th century competition between the Soviet Union and the United States for supremacy in space exploration. Between 1957 and 1975, Cold War rivalry between the two nations focused on attaining firsts in space exploration, which were seen as necessary for national...
, though well behind the several-day record set by the Soviet
Soviet Union
The Soviet Union , officially the Union of Soviet Socialist Republics , was a constitutionally socialist state that existed in Eurasia between 1922 and 1991....
Vostok 3
Vostok 3
Vostok 3 was a spaceflight of the Soviet space program intended to determine the ability of the human body to function in conditions of weightlessness and test the endurance of the Vostok 3KA spacecraft over longer flights...
earlier in the year. It confirmed the Mercury spacecraft's durability ahead of the one-day Mercury-Atlas 9
Mercury-Atlas 9
Mercury-Atlas 9 was the final manned 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...
mission that followed in 1963.
Planning began for the third orbital mission in February 1962, aiming for a six-or-seven-orbit flight to build on the previous three-orbit missions. NASA officially announced the mission to the public on June 27, and the flight plan was finalised in late July. The mission focused on engineering tests rather than on scientific experimentation. The mission finally launched on the morning of October 3, having been delayed two weeks because of problems with the Atlas booster
Atlas LV-3B
The Atlas LV-3B, Atlas D Mercury Launch Vehicle or Mercury-Atlas Launch Vehicle, was a man-rated expendable launch system used as part of the United States Project Mercury to send astronauts into low Earth orbit. It was derived from the SM-65D Atlas missile, and was a member of the Atlas family of...
. A series of minor booster problems during launch and a faulty temperature controller in Schirra's pressure suit
Pressure suit
A pressure suit is a protective suit worn by high-altitude pilots who may fly at altitudes where the air pressure is too low for an unprotected person to survive, even breathing pure oxygen at positive pressure. Such suits may be either full-pressure or partial-pressure...
were the only technical problems noted during the flight. The spacecraft orbited in both automated and passive flight modes for prolonged periods while the pilot monitored it and carried out some minor scientific experiments. After six orbits, the capsule landed in the Pacific Ocean half a mile from the recovery carrier
Aircraft carrier
An aircraft carrier is a warship designed with a primary mission of deploying and recovering aircraft, acting as a seagoing airbase. Aircraft carriers thus allow a naval force to project air power worldwide without having to depend on local bases for staging aircraft operations...
, and was hoisted aboard for Schirra to disembark.
The scientific results of the mission were mixed. The astronaut returned healthy and was released after nine hours of confinement in a low-gravity environment. Observation of the Earth's surface proved unproductive, however, because of heavy cloud cover and bad photographic exposures. The public and political reaction was muted compared with that of earlier missions, as the Cuban Missile Crisis
Cuban Missile Crisis
The Cuban Missile Crisis was a confrontation among the Soviet Union, Cuba and the United States in October 1962, during the Cold War...
quickly eclipsed the space race
Space Race
The Space Race was a mid-to-late 20th century competition between the Soviet Union and the United States for supremacy in space exploration. Between 1957 and 1975, Cold War rivalry between the two nations focused on attaining firsts in space exploration, which were seen as necessary for national...
in the news. The mission was a technical success: all the engineering objectives had been completed without significant malfunctions, and the spacecraft had used even less fuel than expected. This confirmed the capabilities of the Mercury spacecraft and allowed NASA to plan with confidence for a day-long flight, MA-9
Mercury-Atlas 9
Mercury-Atlas 9 was the final manned 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...
, which had been an early goal of the Mercury program.
Background
By 1962, both the United States and the Soviet Union had flown two solo spaceflights as part of the "Space RaceSpace Race
The Space Race was a mid-to-late 20th century competition between the Soviet Union and the United States for supremacy in space exploration. Between 1957 and 1975, Cold War rivalry between the two nations focused on attaining firsts in space exploration, which were seen as necessary for national...
". There was a widespread perception, however, that the United States was falling behind; its two missions had been suborbital and had lasted only a few minutes. The Soviet missions had both orbited the Earth, and the second, Vostok 2
Vostok 2
Vostok 2 was a Soviet space mission which carried cosmonaut Gherman Titov into orbit for a full day in order to study the effects of a more prolonged period of weightlessness on the human body...
, had remained in orbit for a full day. Using the new high-powered Atlas booster
SM-65D Atlas
The SM-65D Atlas, or Atlas D, was the first operational version of the U.S. Atlas missile. It first flew on April 14, 1959. Atlas D missiles were also used for orbital launches, both with upper stages and on their own as a stage-and-a-half vehicle....
, the coming orbital Mercury missions were expected to shorten the gap between the two countries.
NASA announced the first two orbital missions at the end of November 1961, shortly after the Mercury-Atlas 5
Mercury-Atlas 5
Mercury-Atlas 5 was an American unmanned spaceflight of the Mercury program. It was launched on November 29, 1961 with Enos the Chimp, a chimpanzee, aboard...
(MA-5) test flight, which had carried a chimpanzee
Enos (chimpanzee)
Enos was the first chimpanzee that was launched into Earth orbit.Enos was purchased from the Miami Rare Bird Farm on April 3, 1960. He completed more than 1,250 hours of training for his mission at the University of Kentucky and Holloman Air Force Base...
and twice orbited the Earth. MA-6
Mercury-Atlas 6
Mercury-Atlas 6 was a human spaceflight mission conducted by NASA, the space agency of the United States. As part of Project Mercury, MA-6 was the successful first attempt by NASA to place an astronaut into orbit. The MA-6 mission was launched February 20, 1962. It made three orbits of the Earth,...
was planned as the first orbital flight, with John Glenn
John Glenn
John Herschel Glenn, Jr. is a former United States Marine Corps pilot, astronaut, and United States senator who was the first American to orbit the Earth and the third American in space. Glenn was a Marine Corps fighter pilot before joining NASA's Mercury program as a member of NASA's original...
as the primary crew and Scott Carpenter
Scott Carpenter
Malcolm Scott Carpenter is an American engineer, former test pilot, astronaut, and aquanaut. He is best known as one of the original seven astronauts selected for NASA's Project Mercury in April 1959....
as his backup. The follow-up mission, MA-7
Mercury-Atlas 7
-Backup crew:-Crew notes:The original prime crew for Mercury Atlas-7 was to have been Deke Slayton, with Schirra as his back-up. However Slayton was removed from all flight crew availability after the discovery of cardiac arrhythmia during a training run in the g-loading centrifuge...
was to be crewed by Deke Slayton
Deke Slayton
Donald Kent Slayton , better known as Deke Slayton, was an American World War II pilot and later, one of the original NASA Mercury Seven astronauts....
, with Wally Schirra
Wally Schirra
Walter Marty Schirra, Jr. was an American test pilot, United States Navy officer, and one of the original Mercury 7 astronauts chosen for the Project Mercury, America's effort to put humans in space. He is the only person to fly in all of America's first three space programs...
as his backup. In February 1962, the first draft planning began for MA-8, the third orbital mission, with a goal of "six or seven" orbits, as an intermediate step towards a day-long 18-orbit flight. The decision to move to six orbits rather than seven was driven by the mission rules on contingency recovery operations; a seventh orbit would have required significant additional recovery forces to be able to reach the capsule anywhere on its trajectory within eighteen hours. The six-orbit profile had other effects on the recovery plans; the optimum recovery point was moved to the Pacific Ocean, rather than the Atlantic.
On March 15, 1962, NASA announced that Slayton was medically unfit and would be replaced by Scott Carpenter
Scott Carpenter
Malcolm Scott Carpenter is an American engineer, former test pilot, astronaut, and aquanaut. He is best known as one of the original seven astronauts selected for NASA's Project Mercury in April 1959....
as the prime crew for the MA-7 mission. The decision to replace him with Carpenter, rather than his official backup Schirra, was justified by the large amount of training Carpenter had managed while preparing for the long-delayed MA-6 mission. After the success of the MA-6 and MA-7 missions, both of three orbits, pressure began to mount to fly an extended mission. On June 27, 1962, NASA first announced its plan for the upcoming MA-8 mission, which would last for "as many as six" orbits. Schirra was named as the prime crew for MA-8, with Gordon Cooper
Gordon Cooper
Leroy Gordon Cooper, Jr. , also known as Gordon Cooper, was an American aeronautical engineer, test pilot and NASA astronaut. Cooper was one of the seven original astronauts in Project Mercury, the first manned space effort by the United States...
as his backup, repeating the backup-one fly-one pattern set by the previous two missions. The pattern would be repeated for MA-9
Mercury-Atlas 9
Mercury-Atlas 9 was the final manned 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...
, flown by Cooper, and the planned but cancelled MA-10
Mercury-Atlas 10
Mercury-Atlas 10 was a cancelled early manned 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...
, which would have been flown by Cooper's backup, Alan Shepard
Alan Shepard
Alan Bartlett Shepard, Jr. was an American naval aviator, test pilot, flag officer, and NASA astronaut who in 1961 became the second person, and the first American, in space. This Mercury flight was designed to enter space, but not to achieve orbit...
.
The Soviet Union had not flown any further flights by the time MA-7 landed, putting both sides of the space race
Space Race
The Space Race was a mid-to-late 20th century competition between the Soviet Union and the United States for supremacy in space exploration. Between 1957 and 1975, Cold War rivalry between the two nations focused on attaining firsts in space exploration, which were seen as necessary for national...
even at two orbital flights each. While the Soviets had flown for longer, the Mercury program was gaining momentum, with a six-orbit mission currently planned and press speculation about a one-day mission. However, in mid-August, the Soviet Union launched two orbital missions, Vostok 3
Vostok 3
Vostok 3 was a spaceflight of the Soviet space program intended to determine the ability of the human body to function in conditions of weightlessness and test the endurance of the Vostok 3KA spacecraft over longer flights...
and Vostok 4
Vostok 4
Vostok 4 was a mission in the Soviet space program. It was launched a day after Vostok 3 with cosmonaut Pavel Popovich on board—the first time that more than one manned spacecraft were in orbit at the same time. The two Vostok capsules came within of one another and ship-to-ship radio contact was...
, within a day of each other. The two craft were in intersecting orbits, but despite much speculation did not attempt to rendezvous; they completed missions of 64 and 48 orbits respectively, just under four and three days, landing within a few minutes of each other on August 15. This was far ahead of anything currently planned for Mercury, and NASA quickly considered the prospect of modifying a capsule to have an active manoeuvring and rendezvous capability, using technology being developed for the Gemini program. However, after examining the time and safety implications of this proposal, it was decided to abandon the idea and continue with the planned six-orbit mission.
Mission objectives
The original MA-8 flight plan was issued on July 27; although it was revised slightly in August and September, it remained broadly unchanged until launch. This was an improvement on the situation with MA-7, which had had frequent and extensive alterations, making it difficult for the pilot to train efficiently. The aim was for the flight to be an engineering-oriented mission, focusing on the operation of the spacecraft rather than on scientific experimentation, to help pave the way for a future long-duration mission. Schirra chose the name "Sigma 7" for the capsule in reflection of this focus. using the mathematical symbol for summationSummation
Summation is the operation of adding a sequence of numbers; the result is their sum or total. If numbers are added sequentially from left to right, any intermediate result is a partial sum, prefix sum, or running total of the summation. The numbers to be summed may be integers, rational numbers,...
as appropriate for an "engineering evaluation", and the "7" to refer to the seven Mercury astronauts
Mercury Seven
Mercury Seven was the group of seven Mercury astronauts selected by NASA on April 9, 1959. They are also referred to as the Original Seven and Astronaut Group 1...
.
The mission objectives involved evaluating the performance of the spacecraft over six orbits, as well as the effect of prolonged microgravity on the pilot. The specific spacecraft systems would also be evaluated and tested, and the worldwide tracking and communications network would be tested to see how well it would stand up in an extended mission. The flight control experiments included manually turning the spacecraft around, yaw and pitch
Aircraft principal axes
An aircraft in flight is free to rotate in three dimensions: pitch, nose up or down about an axis running from wing to wing), yaw, nose left or right about an axis running up and down; and roll, rotation about an axis running from nose to tail. The axes are alternatively designated as lateral,...
manoeuvres to determine how easy it was to control the spacecraft attitude, realignment of the onboard gyroscopes in flight, and leaving the spacecraft to drift on-orbit.
Four non-engineering scientific experiments were planned, two requiring the active involvement of the astronaut and two completely passive. The first involved the astronaut watching for four high-powered flares while passing over Woomera, Australia, and for a xenon arc lamp
Xenon arc lamp
A xenon arc lamp is a specialized type of gas discharge lamp, an electric light that produces light by passing electricity through ionized xenon gas at high pressure to produce a bright white light that closely mimics natural sunlight...
while passing over Durban, South Africa. The second involved two sets of photographs to be taken using a 70mm Hasselblad camera as well as conventional color photographs of the Earth from orbit. Focusing on geological features and cloud patterns, photographs were to be taken through a set of colored filters provided by the U. S. Weather Bureau. The latter were intended to help calibrate the spectral reflectivity of clouds and surface features, which in turn would help improve the cameras on future weather satellites. The passive experimentation packages were two sets of radiation-sensitive photographic films, from the Goddard Space Flight Center
Goddard Space Flight Center
The Goddard Space Flight Center is a major NASA space research laboratory established on May 1, 1959 as NASA's first space flight center. GSFC employs approximately 10,000 civil servants and contractors, and is located approximately northeast of Washington, D.C. in Greenbelt, Maryland, USA. GSFC,...
and the U. S. Navy School of Aviation Medicine, and a set of eight different experimental ablative materials attached to the outside of the spacecraft to test their performance during re-entry.
Spacecraft modifications
The spacecraft and booster were almost identical to those used on the two preceding Mercury orbital flights. The spacecraft had heating blankets removed from the retrorocketRetrorocket
A retrorocket is a rocket engine providing thrust opposing the motion of a spacecraft, thereby causing it to decelerate.-History:...
motors, to save weight, and a SOFAR bomb
Sofar bomb
In oceanography, a sofar bomb , occasionally also referred to as a sofar disc, is a long-range position-fixing system that uses explosive sounds in the deep sound channel of the ocean to pinpoint the location of ships or crashed planes...
was added. This would be ejected at the time the main parachute was deployed, and would help recovery crews find the spacecraft after it landed. A number of modifications were made to the reaction control system
Reaction control system
A reaction control system is a subsystem of a spacecraft whose purpose is attitude control and steering by the use of thrusters. An RCS system is capable of providing small amounts of thrust in any desired direction or combination of directions. An RCS is also capable of providing torque to allow...
, and the communications equipment was upgraded.
The Atlas booster had been modified since the previous flight, and now included a modified fuel injector and a new hypergolic fuel igniter instead of the original pyrotechnic igniter.
Mission preparation
The capsule built for the mission, Mercury Spacecraft #16, had been delivered to Cape CanaveralKennedy Space Center
The John F. Kennedy Space Center is the NASA installation that has been the launch site for every United States human space flight since 1968. Although such flights are currently on hiatus, KSC continues to manage and operate unmanned rocket launch facilities for America's civilian space program...
on January 16, 1962. The Atlas LV-3B
Atlas LV-3B
The Atlas LV-3B, Atlas D Mercury Launch Vehicle or Mercury-Atlas Launch Vehicle, was a man-rated expendable launch system used as part of the United States Project Mercury to send astronauts into low Earth orbit. It was derived from the SM-65D Atlas missile, and was a member of the Atlas family of...
booster assigned to the mission, number 113-D, was accepted by NASA at the Convair plant on July 27 and delivered on August 8. In late July, the launch date was set for September 18, but delays with the Atlas booster's delivery and a series of technical concerns with the safety of the rocket motors caused it to be pushed back several weeks. On September 6, the tests were scheduled to continue until September 24, which allowed for a probable launch on October 3. The booster was test-fired on September 8 to test changes to the engine combustion, and reported as ready for assembly on September 18.
Concerns had been raised that the radiation belt produced in orbit by the recent Operation Dominic nuclear tests would be dangerous to manned space missions, but an extensive study announced in early September declared that it was safe to fly. While the outside of the capsule was expected to receive a dosage of around 500 röntgens, the study concluded that shielding and the effect of the spacecraft structure would reduce this to around 8 röntgens experienced by the astronaut, well within established tolerance limits.
Schirra began training for the mission in early July, logging 29 hours in simulators as well as 31 hours in the spacecraft itself. This included multiple systems tests and three simulated flights, culminating in a six-and-a-half-hour simulated flight on September 29, with the spacecraft and booster fully stacked on the pad. Highlights of the training period included a visit from President John F. Kennedy
John F. Kennedy
John Fitzgerald "Jack" Kennedy , often referred to by his initials JFK, was the 35th President of the United States, serving from 1961 until his assassination in 1963....
on September 11.
The mission was reported as ready to go—"except for the weather"—on October 1. The major concern with the weather was a major tropical storm in the Atlantic
Hurricane Daisy (1962)
Hurricane Daisy was a moderate hurricane in the 1962 Atlantic hurricane season, that caused severe damage in New England, and the Canadian Maritimes. The fourth named storm of the 1962 Atlantic hurricane season, it became a tropical depression on September 29, while moving west-northwest. On...
, though there were also worries over a series of typhoons in the Pacific which could pose a problem for recovery operations. On the evening of October 2, the decision was taken to launch the next morning.
Launch
Schirra was awakened at 1:40 am on the morning of October 2, and after a hearty breakfast—including a bluefishBluefish
The bluefish , called tailor in Australia, is a species of popular marine gamefish found in all climates. It is the sole species of the Pomatomidae family....
he had speared
Spearfishing
Spearfishing is an ancient method of fishing that has been used throughout the world for millennia. Early civilizations were familiar with the custom of spearing fish from rivers and streams using sharpened sticks....
the day before—and a brief physical he left for the launchpad at around 4 am. He entered the spacecraft at 4:41, where he found a steak sandwich left for him in the 'glove compartment', and began the pre-launch checks. The launch countdown proceeded as planned until 6:15, when there was a 15-minute hold to allow the Canary Islands
Canary Islands
The Canary Islands , also known as the Canaries , is a Spanish archipelago located just off the northwest coast of mainland Africa, 100 km west of the border between Morocco and the Western Sahara. The Canaries are a Spanish autonomous community and an outermost region of the European Union...
tracking station to repair a radar set. The countdown resumed at 6:30 and proceeded to booster ignition with no further delays. The launch itself began nominally, but after 10 seconds the booster began to roll clockwise, threatening a possible abort. However, after a few tense moments, the roll stopped as suddenly as it had begun. This was later identified as being due to a slight misalignment of the main engines and was kept under control by the booster's vernier thrusters.
Around three and a half minutes into the flight, Deke Slayton
Deke Slayton
Donald Kent Slayton , better known as Deke Slayton, was an American World War II pilot and later, one of the original NASA Mercury Seven astronauts....
, the capsule communicator, cut in to ask Schirra "Are you a turtle today?" Schirra, nonplussed, announced that he was switching to the on-board voice recorder (rather than the broadcast radio circuit) to leave his answer; the mission communications transcript noted this as "[correct answer recorded]". The "turtle club
Ancient Order of Turtles
The Ancient and Honorable Order of Turtles started as an informal "drinking club" between World War II pilots, self-described as "an honorable drinking fraternity composed of ladies and gentlemen of the highest morals and good character, who are never vulgar."To gain admission, one...
" was a recurrent joke among the astronaut corps; on being challenged with this question, the correct response was "you bet your sweet ass I am", with a failure to give the password being punishable by buying a round of drinks. Schirra noted later that he "wasn't ready for all the world to hear it", and chose to use the on-board recorder to avoid saying the answer over the air.
The booster engines cut off 2 seconds earlier than planned, but the sustainer engine burned for about 10 seconds longer than intended, giving an extra 15 feet per second (4.6 m/s) of velocity and putting the spacecraft in a slightly higher orbit than planned. Initial analysis of the trajectory confirmed that the capsule could remain in a stable orbit for at least seven orbits, ensuring there would be no need for an early de-orbit.
Orbital activities
Crossing over the eastern coast of Africa, he began to feel overheated; this problem was also apparent to the ground controllers, who were having a debate with the flight surgeon over whether it was safe to continue or if the mission should be ended after the first orbit. The flight director, Christopher Kraft
Christopher C. Kraft, Jr.
Christopher Columbus Kraft, Jr. is a retired NASA engineer and manager who was instrumental in establishing the agency's Mission Control operation...
, followed the surgeon's advice to see if the problem would settle, and gave the go for a second orbit. Schirra eventually stabilized the problem over time, slowly dialling the suit's control knob to a high cooling setting; he compared the heat to that of "mowing a lawn in Texas".
Over Australia, Schirra watched for a flare launched from the ground, but it was occluded by clouds; he, was however, able to see lightning and the lit outline of Brisbane
Brisbane
Brisbane is the capital and most populous city in the Australian state of Queensland and the third most populous city in Australia. Brisbane's metropolitan area has a population of over 2 million, and the South East Queensland urban conurbation, centred around Brisbane, encompasses a population of...
. Through the night pass over the Pacific, he tested the capsule's on-board periscope, though he found it difficult to use and quickly covered it up as soon as the sun rose. Crossing over Mexico, he reported that he was in "chimp configuration", with the capsule running entirely on automatic without any input from the pilot, and as he began his second orbit began testing a yaw manoeuvre using the Earth through the main window as a reference, rather than via the much-maligned periscope.
On the second orbit, he confirmed the existence of Glenn's "fireflies", the shower of small bright particles first reported on MA-6
Mercury-Atlas 6
Mercury-Atlas 6 was a human spaceflight mission conducted by NASA, the space agency of the United States. As part of Project Mercury, MA-6 was the successful first attempt by NASA to place an astronaut into orbit. The MA-6 mission was launched February 20, 1962. It made three orbits of the Earth,...
, and during the night section practiced yaw manoeuvres using first the Moon and then known stars as reference points. The second proved difficult to work with, as the small windows of the Mercury capsule gave a very limited field of view, making it hard to identify constellations. Travelling across the Pacific, he again fell back into automatic flight, chatting with Gus Grissom
Gus Grissom
Virgil Ivan Grissom , , better known as Gus Grissom, was one of the original NASA Project Mercury astronauts and a United States Air Force pilot...
at the Hawaiian tracking station about the qualities of the manual control system.
As he began the third orbit, Schirra disconnected the spacecraft's gyroscopes, turned off part of the electrical power system, and let the capsule drift. He took advantage of this quiet period to test his spatial awareness and motor control, which he found was broadly unaffected by weightlessness
Weightlessness
Weightlessness is the condition that exists for an object or person when they experience little or no acceleration except the acceleration that defines their inertial trajectory, or the trajectory of pure free-fall...
, and to eat a light meal. He powered the spacecraft back up over the Indian Ocean, and continued over the Pacific. At Hawaii, he was given clearance for a full six-orbit mission, and as he crossed over towards California shut down the electrical power for a second period of drifting flight, during which he occupied himself taking photographs with the onboard camera.
On the fourth orbit, drifting in an inverted spacecraft with the Earth 'above' him, Schirra continued his photography and attempted—unsuccessfully—to spot the Echo 1 satellite while passing over East Africa. As he approached California, he spoke briefly to John Glenn
John Glenn
John Herschel Glenn, Jr. is a former United States Marine Corps pilot, astronaut, and United States senator who was the first American to orbit the Earth and the third American in space. Glenn was a Marine Corps fighter pilot before joining NASA's Mercury program as a member of NASA's original...
in a two-minute conversation broadcast live across the United States on radio and television. Problems began to recur with the pressure suit, with water condensing on the faceplate; Schirra, concerned about the internal temperature, avoided opening the visor to clean it for fear that the suit temperature would misbehave again.
By the fifth orbit, Schirra had begun to relax, commenting that it was the first rest he had had since December 1961. He used a small bungee cord
Bungee cord
A bungee cord , also known as a shock cord, is an elastic cord composed of one or more elastic strands forming a core, usually covered in a woven cotton or polypropylene sheath...
exercise device for "a little bit of stretching", before dropping into manual attitude control, where he reported a sudden burst of oversteering and high fuel use. Over the Atlantic he returned to observation and photography; he failed to spot the planned high-power light near Durban
Durban
Durban is the largest city in the South African province of KwaZulu-Natal and the third largest city in South Africa. It forms part of the eThekwini metropolitan municipality. Durban is famous for being the busiest port in South Africa. It is also seen as one of the major centres of tourism...
, in South Africa, due to cloud cover, but did make out the brightly lit city of Port Elizabeth. Over the Philippines, he reported on his fuel status; after four and a half of the planned six orbits, he still had eighty percent remaining in both manual and automatic fuel tanks. Passing over Quito, Ecuador, towards the end of his fifth orbit, Schirra was asked by the tracking station if he had any message to pass on "in Spanish to the fellows down here", and he made some comments on how beautiful the country appeared from orbit, ending with a cheery "Buenos Dias, y'all!" Schirra later noted that he was "furious" at this point—he was preparing for re-entry and didn't want to be distracted with making public statements.
The sixth orbit was dominated by preparations for re-entry, though Schirra was able to take a last set of photographs of South America and try another set of spatial-orientation tests. He armed the retrorocket
Retrorocket
A retrorocket is a rocket engine providing thrust opposing the motion of a spacecraft, thereby causing it to decelerate.-History:...
s passing over the western Pacific, and fired the first one at 8:52 mission elapsed time
Mission Elapsed Time
Mission Elapsed Time is used by NASA during their space missions, most notably during their Space Shuttle missions. Because so much of the mission depends on the time of launch, all events after launch are scheduled on the Mission Elapsed Time. This avoids constant rescheduling of events in case...
. The automatic control system held the capsule "steady as a rock" during this period, though after the retrorockets had stopped firing Schirra noted that the system had burned almost a quarter of its fuel in the process.
Re-entry and recovery
Atmospheric reentry
Atmospheric entry is the movement of human-made or natural objects as they enter the atmosphere of a celestial body from outer space—in the case of Earth from an altitude above the Kármán Line,...
after the de-orbit burn, Schirra used the high-power thrusters to put the capsule in the correct orientation, noting that the attitude control felt "sloppy". He then enabled the rate stabilization control system, an automatic control method which used up fuel at a very high rate, to maintain control during re-entry; this was a specific engineering request, and it dismayed Schirra to see the fuel he had husbanded for six orbits be used so quickly.
The local recovery group in the prime target area, in the central Pacific, consisted of an aircraft carrier, the USS Kearsarge
USS Kearsarge (CV-33)
USS Kearsarge was one of 24 s completed during or shortly after World War II for the United States Navy. The ship was the third US Navy ship to bear the name, and was named for a Civil War-era steam sloop. Kearsarge was commissioned in March 1946...
, in the centre of the landing area, with three destroyers strung out along the orbital path. Four search aircraft were also assigned to the area, and three recovery helicopters were based aboard the Kearsarge.
The Kearsarge picked up the capsule on radar while still 200 miles (321.9 km) from landing; 90 miles (144.8 km) further up the landing path, the destroyer USS Renshaw
USS Renshaw (DD-499)
USS Renshaw , a , was the third ship of the United States Navy of that name, in honor of Commander William B. Renshaw.Renshaw was laid down 7 May 1942 by the Federal Shipbuilding & Drydock Company in Kearny, New Jersey; launched on 13 October 1942, sponsored by Miss Dorothy Lillian Renshaw; and...
reported a sonic boom as it passed overhead. At 40000 feet (12,192 m), Schirra deployed the drogue parachute
Drogue parachute
A drogue parachute is a parachute designed to be deployed from a rapidly moving object in order to slow the object, or to provide control and stability, or as a pilot parachute to deploy a larger parachute...
, and then the main parachute at 15000 feet (4,572 m). The landing was surprisingly precise, 4.5 miles (7.2 km) from the target point and 0.5 mile (0.80467 km) from the Kearsarge, and Schirra joked that he was on course for the recovery carrier's "number three elevator". The capsule hit the water, sank and bobbed to the surface again, righting itself after about 30 seconds. Three pararescue swimmers were dropped by one of the helicopters to help him climb out, but Schirra radioed that he would prefer to be towed to the carrier, and a whaleboat
Whaleboat
A whaleboat is a type of open boat that is relatively narrow and pointed at both ends, enabling it to move either forwards or backwards equally well. It was originally developed for whaling, and later became popular for work along beaches, since it does not need to be turned around for beaching or...
from the Kearsarge was sent with a line.
Forty minutes after landing, Sigma 7 was hoisted aboard the Kearsarge; five minutes later, Schirra blew the explosive hatch and climbed out to a waiting crowd. After doing this, examinations showed clear bruising on his hand from operating the heavy ejector switch, which he felt provided an important vindication for fellow pilot Gus Grissom
Gus Grissom
Virgil Ivan Grissom , , better known as Gus Grissom, was one of the original NASA Project Mercury astronauts and a United States Air Force pilot...
's hatch expulsion accident during the Liberty Bell 7 mission. Grissom had maintained that the hatch blew without his input; the fact that he had no bruising was seen as evidence that he had not blown the hatch early and sunk his capsule, but that it was a mechanical malfunction.
Schirra remained aboard for three days of medical tests and debriefing before disembarking, while the spacecraft was offloaded at Midway Island and transferred to an aircraft for further transport. It was returned to Cape Canaveral for analysis, with the long-term intention of putting it on permanent display.
The spent Atlas booster re-entered the atmosphere on October 4, the day after the launch, and was burned up. After a period on display at the Johnson Space Center, the capsule is currently displayed at the United States Astronaut Hall of Fame
Astronaut Hall of Fame
The United States Astronaut Hall of Fame, located just south of Titusville, Florida, honors American astronauts and features the world's largest collection of their personal memorabilia, focusing on those astronauts who have been inducted into the Hall; as well as Sigma 7, the fifth manned Mercury...
, Titusville, Florida
Titusville, Florida
Titusville is a city in Brevard County, Florida in the United States. It is the county seat of Brevard County. Nicknamed Space City, USA, Titusville is on the Indian River, west of Merritt Island and the Kennedy Space Center and south-southwest of the Canaveral National Seashore...
.
Post-flight
The post-flight analysis reported no major malfunctions—the only troublesome anomaly being the suit temperature controls— and all the engineering objectives of the mission were deemed successfully completed. The fuel-conservation measures were found to have worked particularly well, with even less fuel than anticipated being consumed; despite the technical changes, the official report gave full credit for this to the pilot. The medical analysis found no significant physiological effects from nine hours of weightlessness, and noted that Schirra had received no significant radiation exposure. Analysis of the radiation-sensitive plates confirmed that there had been a very low radioactive flux inside the spacecraft, and the six ablative materials tested were all deemed broadly satisfactory despite some difficulty comparing them to each other.Scientifically, the light-observation experiments were unsuccessful, as both target locations were covered by thick cloud cover. However, Schirra was able to view lightning near Woomera, and noted the lights of a city a few hundred miles from Durban. The filtered photography for the Weather Bureau worked as planned, with 15 photographs taken; the conventional color photography was less successful, with several of the 14 photographs unusable due to overexposure or excess cloud cover. In the end, the conventional photographs were not used for scientific examination due to these problems. Schirra noted that the sheer amount of cloud coverage, worldwide, could provide problems for future activity of this kind; however, Africa, and the south-western United States, were perfectly clear.
Schirra's post-flight report noted the "fireflies" seen on the previous two missions, and emphasized the remarkable visual effect of the thick band of the atmosphere visible around the horizon. However, he was unimpressed with the view of Earth from space; the amount of detail he could make out compared well with that from high-flying aircraft, and he told debriefers that it was "nothing new" compared to flight at 50000 feet (15,240 m). Overall, he concluded that Sigma 7 was on "the top of the list" of aircraft he had flown, displacing the F8F Bearcat
F8F Bearcat
The Grumman F8F Bearcat was an American single-engine naval fighter aircraft of the 1940s. It went on to serve into the mid-20th century in the United States Navy and other air forces, and would be the company's final piston engined fighter aircraft...
, a naval piston-engined fighter, while the mission itself had been "textbook".
Schirra gave a public lecture at Rice University
Rice University
William Marsh Rice University, commonly referred to as Rice University or Rice, is a private research university located on a heavily wooded campus in Houston, Texas, United States...
after returning to Houston, where he received a motorcade through the city. However, the Cuban Missile Crisis
Cuban Missile Crisis
The Cuban Missile Crisis was a confrontation among the Soviet Union, Cuba and the United States in October 1962, during the Cold War...
had been steadily escalating through September, and helped drive discussion of Schirra's successful flight down the news schedules; public concern about the relative effectiveness of Soviet and American space launchers was displaced by a more pressing concern over Soviet military rockets. He visited Washington, DC, to receive the NASA Distinguished Service Medal
NASA Distinguished Service Medal
The NASA Distinguished Service Medal is the highest award which may be bestowed by the National Aeronautics and Space Administration of the United States...
from President Kennedy on October 16, the same day Kennedy had first seen U-2 photographs of missile sites in Cuba; the meeting was friendly and informal despite the circumstances. Robert Kennedy, Schirra later noted, took him aside and sounded him out about a potential political career, the same way he had sounded out John Glenn
John Glenn
John Herschel Glenn, Jr. is a former United States Marine Corps pilot, astronaut, and United States senator who was the first American to orbit the Earth and the third American in space. Glenn was a Marine Corps fighter pilot before joining NASA's Mercury program as a member of NASA's original...
a year earlier. Unlike Glenn, however, Schirra politely turned the suggestion down, and chose to remain with NASA. His later career saw him commanding the backup crew for the first Gemini mission, then the prime crew for the 1965 Gemini 6A
Gemini 6A
-Backup crew:-Mission parameters:* Mass: * Perigee: * Apogee: * Inclination: 28.97°* Period: 88.7 min-Stationkeeping with GT-7:* Start: December 15, 1965 19:33 UTC* End: December 16, 1965 00:52 UTC-Objectives:...
mission, where he flew the first active rendezvous between two spacecraft - earlier plans for it to conduct the first on-orbit docking had been cancelled - and finally commanding the first Apollo mission, Apollo 7
Apollo 7
Apollo 7 was the first manned mission in the American Apollo space program, and the first manned US space flight after a cabin fire killed the crew of what was to have been the first manned mission, AS-204 , during a launch pad test in 1967...
, in 1968. He eventually resigned from NASA in the summer of 1969.
The success of MA-8 made the preparation for MA-9
Mercury-Atlas 9
Mercury-Atlas 9 was the final manned 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...
"considerably easier", though it did cause some observers to suggest the program should be ended abruptly in order to conclude on a clear note of success, rather than risking another—potentially catastrophic—flight. However, this was not a view shared by the NASA planners, who had been pressing for a one-day Mercury mission since mid-1961, when it first began to seem technically feasible. To prepare the spacecraft for a long-duration mission involved trimming as much on-board weight as possible to offset the additional consumables required. The changes made to the capsule hardware on MA-8 were now used to justify the removal of 12 pounds (5.4 kg) of control equipment and 5 pounds (2.3 kg) of radio equipment, as well as the 76 pounds (34.5 kg) periscope which Schirra had found so unhelpful. In total, there were 183 alterations listed between the capsules for the MA-8 and MA-9 missions. The spacecraft was to be equipped with several cameras, building on Schirra's photographic work, though weight and power limitations did restrict the amount of scientific experiments that could be scheduled.