Mercury-Atlas 6 (MA-6) was the first crewed American
orbital spaceflight
An orbital spaceflight (or orbital flight) is a spaceflight in which a spacecraft is placed on a trajectory where it could remain in space for at least one orbit. To do this around the Earth, it must be on a free trajectory which has an altit ...
, which took place on February 20, 1962. Piloted by astronaut
John Glenn and operated by
NASA
The National Aeronautics and Space Administration (NASA ) is an independent agency of the US federal government responsible for the civil space program, aeronautics research, and space research.
NASA was established in 1958, succeeding t ...
as part of
Project Mercury
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 Un ...
, it was the fifth
human spaceflight
Human spaceflight (also referred to as manned spaceflight or crewed spaceflight) is spaceflight with a crew or passengers aboard a spacecraft, often with the spacecraft being operated directly by the onboard human crew. Spacecraft can also be ...
, preceded by
Soviet
The Soviet Union,. officially the Union of Soviet Socialist Republics. (USSR),. was a List of former transcontinental countries#Since 1700, transcontinental country that spanned much of Eurasia from 1922 to 1991. A flagship communist state, ...
orbital flights
Vostok 1
Vostok 1 (russian: link=no, Восток, ''East'' or '' Orient'' 1) was the first spaceflight of the Vostok programme and the first human orbital spaceflight in history. The Vostok 3KA space capsule was launched from Baikonur Cosmodrome on Apr ...
and
2 and American
sub-orbital
A sub-orbital spaceflight is a spaceflight in which the spacecraft reaches outer space, but its trajectory intersects the atmosphere or surface of the gravitating body from which it was launched, so that it will not complete one orbital re ...
flights
Mercury-Redstone 3
Mercury-Redstone 3, or ''Freedom 7'', was the first United States human spaceflight, on May 5, 1961, piloted by astronaut Alan Shepard. It was the first crewed flight of Project Mercury. The project had the ultimate objective of putting an as ...
and
4.
The Mercury spacecraft, named ''Friendship 7'', was carried to orbit by an
Atlas LV-3B
The Atlas LV-3B, Atlas D Mercury Launch Vehicle or Mercury-Atlas Launch Vehicle, was a human-rated expendable launch system used as part of the United States Project Mercury to send astronauts into low Earth orbit. Manufactured by Convair, it w ...
launch vehicle lifting off from
Launch Complex 14 at
Cape Canaveral
, image = cape canaveral.jpg
, image_size = 300
, caption = View of Cape Canaveral from space in 1991
, map = Florida#USA
, map_width = 300
, type =Cape
, map_caption = Location in Florida
, location ...
,
Florida
Florida is a state located in the Southeastern region of the United States. Florida is bordered to the west by the Gulf of Mexico, to the northwest by Alabama, to the north by Georgia, to the east by the Bahamas and Atlantic Ocean, and to ...
. After three orbits, the spacecraft
re-entered the Earth's atmosphere, splashed down in the
North Atlantic Ocean
The Atlantic Ocean is the second-largest of the world's five oceans, with an area of about . It covers approximately 20% of Earth's surface and about 29% of its water surface area. It is known to separate the "Old World" of Africa, Europe an ...
, and was safely taken aboard . Total mission flight time was four hours 55 minutes and 23 seconds.
The event was named an
IEEE Milestone in 2011.
Preparation
After the successful completion of the
Mercury-Atlas 5
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 south of Bermuda, and Enos became the first pri ...
flight that carried
Enos Enos or Enosh (Hebrew: , Standard ''Enosh'', Tiberian ''ʼĔnôš''; "mortal man”) may refer to:
People in religious scripture
* Enos (biblical figure), a genealogical figure in the Bible.
* The Book of Enos, one of the books that make up the B ...
, a chimpanzee, in late November 1961, a press conference was held in early December. Reporters asked NASA's
Robert Gilruth
Robert Rowe Gilruth (October 8, 1913 – August 17, 2000) was an American aerospace engineer and an aviation/space pioneer who was the first director of NASA's Manned Spacecraft Center, later renamed the Lyndon B. Johnson Space Center.
He worked ...
who would be the first U.S. astronaut in orbit, piloting M-A6. He then announced the team members for the next two Mercury missions. John H. Glenn was selected as prime pilot for the first mission (M-A6), with
M. Scott Carpenter
Malcolm Scott Carpenter (May 1, 1925 – October 10, 2013) 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 Mercu ...
as his backup.
Donald K. Slayton
Donald Kent "Deke" Slayton (March 1, 1924 – June 13, 1993) was a United States Air Force pilot, aeronautical engineer, and test pilot who was selected as one of the original NASA Mercury Seven astronauts. He went on to become NASA's first ...
and
Walter M. Schirra were pilot and backup, respectively, for the second mission,
Mercury-Atlas 7
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 ...
.
The MA-6 launch vehicle, Atlas #109-D, arrived at Cape Canaveral the evening of November 30, 1961. NASA had wanted to launch M-A6 in 1961 (hoping to orbit an astronaut in the same calendar year as the Soviets did), but by early December it was apparent that the mission hardware would not be ready for launch until early 1962.
Mercury spacecraft #13 began taking form on McDonnell's St. Louis, Missouri assembly line in May 1960. It was chosen for the MA-6 mission in October 1960 and delivered to Cape Canaveral on August 27, 1961. Mercury spacecraft #13 and Atlas #109-D were stacked on the pad at Launch Complex 14 on January 2, 1962.
As the effects of orbital space flight on humans were unknown except to the Soviets, who were keeping whatever knowledge they had a secret, Glenn was prepared with an onboard medical kit consisting of
morphine
Morphine is a strong opiate that is found naturally in opium, a dark brown resin in poppies (''Papaver somniferum''). It is mainly used as a analgesic, pain medication, and is also commonly used recreational drug, recreationally, or to make ...
for pain relief,
mephentermine sulfate
Mephentermine is a cardiac stimulant.
It has been used as a treatment for hypotension, low blood pressure.
Mephentermine belongs to the class of adrenergic and dopaminergic cardiac stimulants excluding glycosides. Used in the treatment of heart ...
to treat any shock symptoms,
benzylamine hydrochloride to counter motion sickness and
racemic amphetamine sulfate
Amphetamine (contracted from alpha- methylphenethylamine) is a strong central nervous system (CNS) stimulant that is used in the treatment of attention deficit hyperactivity disorder (ADHD), narcolepsy, and obesity. It is also commonly used a ...
, a stimulant. A
survival kit
A survival kit is a package of basic tools and supplies prepared as an aid to survival in an emergency. Civil and military aircraft, lifeboats, and spacecraft are equipped with survival kits.
Survival kits, in a variety of sizes, contain supp ...
was also placed on board to assist Glenn while waiting for recovery after splashdown, including desalter kits, dye marker, distress signal, signal mirrors, signal whistle, first aid kits, shark chaser, a PK-2 raft, survival rations, matches, and a radio transceiver.
Prior to MA-6, there had been a reluctance on the part of NASA to permit the use of cameras by astronauts, as it was feared these might prove an unnecessary distraction. Glenn, however, was successful in persuading NASA that he should be allowed to take one on the mission, and a
Minolta Hi-Matic
Hi-Matic was the name of a long-running series of 35 mm cameras made by Minolta. The original Hi-Matic of 1962 was the first Minolta camera to feature automatic exposure and achieved a small degree of fame when a version (the Ansco Autoset) was ta ...
35mm film 35 mm may refer to:
* 135 film, a type of still photography format commonly referred to as 35 mm film
* 35 mm movie film, a type of motion picture film stock
* 35MM 35 mm may refer to:
* 135 film, a type of still photography format ...
camera (which he purchased himself at a local drug store) duly made the trip into orbit. This was modified to be used with pressure suit gloves, although changing the film in a weightless environment proved a difficult operation and during the flight Glenn knocked a film canister which then floated away, ending up behind the instrument panel.
Flight
Delays
The launch date was first announced as January 16, 1962, then postponed to January 20 because of problems with the Atlas rocket fuel tanks. The launch then slipped day by day to January 27 due to unfavorable winter weather. On that day, Glenn was on board Mercury 6 and ready to launch, when, at T-29 minutes, the flight director called off the launch because of thick clouds that would have made it impossible to photograph or film the launch vehicle after the first 20 seconds of the mission (the inability of launch crews to film the failed
Mercury-Atlas 1
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 ...
launch 16 months earlier had proven the importance of flying only in clear skies). The large crowd of reporters gathered at Cape Canaveral for the launch went home, disappointed. Mission Director Walter Williams felt a sense of relief at the bad weather, as there was still a general sense that the spacecraft and booster were not ready to fly yet.
NASA informed the anxious public that the mission would take time to get ready since crewed launches required a high degree of preparation and safety standards. The launch was postponed until February 1, but when technicians began to fuel the Atlas on January 30, they discovered a fuel leak had soaked an internal insulation blanket between the RP-1 and LOX tanks. This caused a two-week delay while necessary repairs were made. On February 14, the launch was again postponed due to weather, which started to break on February 18, and it appeared that February 20 would be a favorable day to attempt a launch.
Launch
Glenn boarded the ''Friendship 7'' spacecraft at 11:03
UTC on February 20 following an hour-and-a-half delay to replace a faulty component in the Atlas's guidance system. The hatch was bolted in place at 12:10 UTC. Most of the 70 hatch bolts had been secured, when one was discovered to be broken. This caused a 42-minute delay while all the bolts were removed, the defective bolt was replaced and the hatch was re-bolted in place. The count was resumed at 11:25 UTC, and the gantry was rolled back at 13:20 UTC. At 13:58 UTC the count was held for 25 minutes while a liquid oxygen propellant valve was repaired.
At 14:47 UTC, after two hours and 17 minutes of holds and three hours and 44 minutes after Glenn entered ''Friendship 7'', engineer
T. J. O'Malley pressed the button in the blockhouse launching the spacecraft.
O'Malley said, "the good Lord ride all the way," and then capsule communicator
Scott Carpenter
Malcolm Scott Carpenter (May 1, 1925 – October 10, 2013) 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 ...
uttered the famous phrase "Godspeed, John Glenn."
Due to a glitch in Glenn's radio, he did not hear the Carpenter phrase during launch.
At liftoff Glenn's pulse rate climbed to 110 beats per minute.
Thirty seconds after liftoff, the General Electric-Burroughs designed guidance system locked onto a radio transponder in the booster to guide the vehicle to orbit. As the Atlas and ''Friendship 7'' passed through
max Q Glenn reported, "Have some vibration area coming up here now." After max Q the flight smoothed out. At two minutes and 14 seconds after launch, the booster engines cut off and dropped away. Then at two minutes and twenty-four seconds, the
escape tower
A launch escape system (LES) or launch abort system (LAS) is a crew-safety system connected to a space capsule that can be used to quickly separate the capsule from its launch vehicle in case of an emergency requiring the abort of the launch, suc ...
was jettisoned, right on schedule.
After the tower was jettisoned, the Atlas and spacecraft pitched over still further, giving Glenn his first view of the horizon. He described the view as "a beautiful sight, looking eastward across the Atlantic". Vibration increased as the last of the fuel supply was used up. Booster performance had been nearly flawless through the entire powered flight. At sustainer engine cut-off, it was found that the Atlas had accelerated the capsule to a speed only 7 ft/s (2 m/s) below nominal. At 14:52 UTC, ''Friendship 7'' was in orbit. Glenn received word that the Atlas had boosted the MA-6 into a trajectory that would stay up for at least seven orbits. Meanwhile, computers at the
Goddard Space Flight Center
The Goddard Space Flight Center (GSFC) is a major NASA space research laboratory located approximately northeast of Washington, D.C. in Greenbelt, Maryland, United States. Established on May 1, 1959 as NASA's first space flight center, GSFC empl ...
in
Maryland
Maryland ( ) is a state in the Mid-Atlantic region of the United States. It shares borders with Virginia, West Virginia, and the District of Columbia to its south and west; Pennsylvania to its north; and Delaware and the Atlantic Ocean to ...
indicated that the MA-6 orbital parameters appeared good enough for almost 100 orbits.
First orbit
When the posigrade rockets fired and separated the capsule from the booster, the five-second rate-damping operation started two and a half seconds late. This caused a substantial roll error as the capsule began its turnaround. The automatic
attitude control system
Spacecraft attitude control is the process of controlling the orientation of a spacecraft (vehicle/satellite) with respect to an inertial frame of reference or another entity such as the celestial sphere, certain fields, and nearby objects, et ...
took 38 seconds to place ''Friendship 7'' into its proper orbital attitude. The turnaround maneuver used of fuel from a total supply of : for automatic and for manual control system. The spacecraft then settled into orbital flight with a velocity of .
''Friendship 7'' began its first orbit with all systems go. It crossed the
Atlantic
The Atlantic Ocean is the second-largest of the world's five oceans, with an area of about . It covers approximately 20% of Earth's surface and about 29% of its water surface area. It is known to separate the " Old World" of Africa, Europe an ...
and passed over the
Canary Islands
The Canary Islands (; es, Canarias, ), also known informally as the Canaries, are a Spanish autonomous community and archipelago in the Atlantic Ocean, in Macaronesia. At their closest point to the African mainland, they are west of Morocc ...
. Controllers there reported all capsule systems in perfect working order. Looking at the
Africa
Africa is the world's second-largest and second-most populous continent, after Asia in both cases. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 6% of Earth's total surface area ...
n coastline, and later the interior over
Kano
Kano may refer to:
Places
*Kano State, a state in Northern Nigeria
* Kano (city), a city in Nigeria, and the capital of Kano State
**Kingdom of Kano, a Hausa kingdom between the 10th and 14th centuries
**Sultanate of Kano, a Hausa kingdom between ...
,
Nigeria
Nigeria ( ), , ig, Naìjíríyà, yo, Nàìjíríà, pcm, Naijá , ff, Naajeeriya, kcg, Naijeriya officially the Federal Republic of Nigeria, is a country in West Africa. It is situated between the Sahel to the north and the Gulf o ...
, Glenn told the tracking station team that he could see a dust storm. Kano flight communicators replied that the winds had been quite heavy for the past week.
Over Kano, Glenn took control of the spacecraft and started a major
yaw adjustment. He allowed the spacecraft to continue the yaw maneuver until it was facing into its flight path. Glenn noticed that the attitude indicators disagreed with what he observed was the true spacecraft attitude. Even with the incorrect instrument readouts, he was pleased to be facing forward instead of backward on his orbital path.
Over the
Indian Ocean
The Indian Ocean is the third-largest of the world's five oceanic divisions, covering or ~19.8% of the water on Earth's surface. It is bounded by Asia to the north, Africa to the west and Australia to the east. To the south it is bounded by th ...
, Glenn observed his first sunset from orbit. He described the moment of twilight as "beautiful". The sky in space was very black, he said, with a thin band of blue along the horizon. He said the sun set fast, but not as quickly as he had expected. For five or six minutes there was a slow reduction in light intensity. Brilliant orange and blue layers spread out 45 to 60 degrees on either side of the sun, tapering gradually toward the horizon. Clouds prevented him from seeing a
mortar flare fired by the Indian Ocean tracking ship as part of a pilot observation experiment.
Continuing his journey on the night side of Earth, nearing the
Australia
Australia, officially the Commonwealth of Australia, is a Sovereign state, sovereign country comprising the mainland of the Australia (continent), Australian continent, the island of Tasmania, and numerous List of islands of Australia, sma ...
n coastline, Glenn made star, weather, and landmark observations. He looked for but failed to see the dim light phenomenon known as the
zodiacal light
The zodiacal light (also called false dawn when seen before sunrise) is a faint glow of diffuse sunlight scattered by interplanetary dust. Brighter around the Sun, it appears in a particularly dark night sky to extend from the Sun's direction in ...
; his eyes had insufficient time to adapt to the darkness.
The spacecraft came into radio range of
Muchea, Australia. At the Mercury Tracking Station there,
Gordon Cooper
Leroy Gordon "Gordo" Cooper Jr. (March 6, 1927 – October 4, 2004) was an American aerospace engineer, test pilot, United States Air Force pilot, and the youngest of the seven original astronauts in Project Mercury, the first human spa ...
was the capsule communicator. Glenn reported that he felt fine and had no problems. He saw a very bright light and what appeared to be the outline of a city. Cooper said that he probably was looking at the lights of
Perth
Perth is the capital and largest city of the Australian state of Western Australia. It is the fourth most populous city in Australia and Oceania, with a population of 2.1 million (80% of the state) living in Greater Perth in 2020. Perth is ...
and its satellite town of
Rockingham. This turned out to be correct; many people in Perth turned on their lights so as to be visible to Glenn as he passed over. "That sure was a short day," he excitedly told Cooper. "That was about the shortest day I've ever run into."
The spacecraft moved across Australia and across the
Pacific
The Pacific Ocean is the largest and deepest of Earth's five oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean (or, depending on definition, to Antarctica) in the south, and is bounded by the continen ...
to
Canton Island
Canton Island (also known as Kanton or Abariringa), previously known as Mary Island, Mary Balcout's Island or Swallow Island, is the largest, northernmost, and , the sole inhabited island of the Phoenix Islands, in the Republic of Kiribati. It i ...
. Glenn experienced a short 45 minute night and prepared the periscope for viewing his first sunrise from orbit. As the sun rose over the island, he saw thousands of "little specks, brilliant specks, floating around outside the capsule"; he momentarily felt that the spacecraft was tumbling or that he was looking into a star field. A quick hard look out of the spacecraft window corrected the illusion and Glenn was sure that the "fireflies", as he called them, were streaming past his spacecraft from ahead. They seemed to flow by slowly but did not seem to be coming from any part of the spacecraft, and they disappeared as ''Friendship 7'' moved into brighter sunlight. It was later determined that they were probably small ice crystals venting from onboard spacecraft systems.
"I am in a big mass of some very small particles, they're brilliantly lit up like they're luminescent. I never saw anything like it. They round a little: they're coming by the capsule and they look like little stars. A whole shower of them coming by. They swirl around the capsule and go in front of the window and they're all brilliantly lighted." Glenn started banging the capsule wall and watched the "fireflies" come off, just as Alan Shepard did.
As the spacecraft crossed the
Kauai, Hawaii
Kauai, () anglicized as Kauai ( ), is geologically the second-oldest of the main Hawaiian Islands (after Niʻihau). With an area of 562.3 square miles (1,456.4 km2), it is the fourth-largest of these islands and the 21st largest island ...
tracking station, Glenn noticed a lot of interference on the HF radio band. As he crossed the Pacific coast of North America, the tracking station at
Guaymas
Guaymas () is a city in Guaymas Municipality, in the southwest part of the state of Sonora, in northwestern Mexico. The city is south of the state capital of Hermosillo, and from the U.S. border. The municipality is located on the Gulf of Cali ...
,
Mexico
Mexico (Spanish: México), officially the United Mexican States, is a country in the southern portion of North America. It is bordered to the north by the United States; to the south and west by the Pacific Ocean; to the southeast by Guatema ...
, informed Mercury Control in Florida that a yaw thruster was causing attitude control problems. Glenn later recalled, this problem "was to stick with me for the rest of the flight".
Glenn noticed the control problem when the automatic stabilization and control system allowed the spacecraft to drift about a degree and a half per second to the right. Glenn switched control to manual-proportional control mode and moved ''Friendship 7'' back to the proper attitude. He tried different control modes to see which used the least fuel to maintain attitude. The manual
fly-by-wire
Fly-by-wire (FBW) is a system that replaces the conventional manual flight controls of an aircraft with an electronic interface. The movements of flight controls are converted to electronic signals transmitted by wires, and flight control co ...
combination used the least fuel. After about twenty minutes, the yaw thruster began working again and Glenn switched back to the automatic control system. It worked for a short time and then began having problems again, this time with the opposite yaw thruster. He then switched back to the manual fly-by-wire system and flew the spacecraft in that mode for the remainder of the flight.
Second orbit
As ''Friendship 7'' crossed
Cape Canaveral
, image = cape canaveral.jpg
, image_size = 300
, caption = View of Cape Canaveral from space in 1991
, map = Florida#USA
, map_width = 300
, type =Cape
, map_caption = Location in Florida
, location ...
at the start of its second orbit, flight systems controller Don Arabian
noticed that "Segment 51", a sensor providing data on the spacecraft landing system, was giving a strange reading. According to the reading, the heat shield and landing bag were no longer locked in position. If this were the case, the heat shield was only being held against the spacecraft by the straps of the retro package. Mercury Control ordered all tracking sites to monitor "Segment 51" closely and advise Glenn that the landing-bag deploy switch should be in the "off" position.
Glenn was not immediately aware of the problem, but he became suspicious when site after site asked him to make sure that the landing-bag deploy switch was off. Meanwhile, ''Friendship 7'' was crossing the Atlantic for the second time. Glenn was busy manually keeping the spacecraft
attitude
Attitude may refer to:
Philosophy and psychology
* Attitude (psychology), an individual's predisposed state of mind regarding a value
* Metaphysics of presence
* Propositional attitude, a relational mental state connecting a person to a pro ...
correct and also trying to accomplish as many of the flight plan tasks as he could.
Crossing over the Canary Islands, Glenn observed that the "fireflies" outside the spacecraft had no connection with gas from the reaction control jets. His suit temperature felt too warm, but he did not take time to adjust it. The Kano, Nigeria and
Zanzibar
Zanzibar (; ; ) is an insular semi-autonomous province which united with Tanganyika in 1964 to form the United Republic of Tanzania. It is an archipelago in the Indian Ocean, off the coast of the mainland, and consists of many small islands ...
sites suddenly noticed a 12 percent drop in the spacecraft secondary oxygen supply.
During his second pass over the Indian Ocean, Glenn found that the Indian Ocean tracking ship was in heavy weather. The tracking station had planned to release balloons for a pilot observation experiment, but instead the ship fired star-shell parachute flares as ''Friendship 7'' passed overhead. Glenn was able to observe the flashes of lightning from storms in the area but was unable to see the flares.
The temperature in Glenn's spacesuit was too warm. It had been since he passed over the Canary Islands, earlier in the second orbit. As he crossed the Indian Ocean, he tried to adjust the suit temperature. As he approached Woomera, Australia, a signal light came on warning him of excess cabin humidity. For the rest of the flight, Glenn had to carefully balance suit cooling against the cabin humidity.
While he was still over Australia, another warning light came on, indicating that the fuel supply for the automatic control system was down to 62%. Mercury Control recommended that Glenn let the spacecraft
attitude
Attitude may refer to:
Philosophy and psychology
* Attitude (psychology), an individual's predisposed state of mind regarding a value
* Metaphysics of presence
* Propositional attitude, a relational mental state connecting a person to a pro ...
drift to conserve fuel.
There were no more problems for ''Friendship 7'' during the remainder of the second orbit. Glenn continued to manually control the spacecraft attitude, not allowing it to drift too far out of alignment. In doing so, he consumed more fuel than a functioning automatic system would have used. Fuel consumption was 6 pounds (2.7 kg) from the automatic tank and 11.8 pounds (5.4 kg) from the manual tank during the second orbit. This amounted to almost 30% of the total fuel supply.
Third orbit
On the third orbit of ''Friendship 7'', the Indian Ocean tracking ship did not attempt to launch any objects for pilot observation experiments, as the cloud coverage was still too thick. When the spacecraft came across Australia for the third time, Glenn joked with Cooper at the
Muchea Tracking Station
Muchea Tracking Station was an Earth station in Australia located close to Muchea in the
Shire of Chittering, about north of Perth, Western Australia, built specifically for NASA's Project Mercury.
History
Muchea was established in 1960, a ...
. Glenn asked Cooper to notify
General Shoup,
Commandant of the Marine Corps
The commandant of the Marine Corps (CMC) is normally the highest-ranking officer in the United States Marine Corps and is a member of the Joint Chiefs of Staff. Joint Chiefs of Staff: composition; functions. The CMC reports directly to the secr ...
, that three orbits should meet the minimum monthly requirement of four hours' flying time. He also asked to be certified as eligible for his regular flight pay.
Reentry
During Glenn's orbits, Mercury Control had been monitoring the problem with "Segment 51". The Hawaiian tracking station asked Glenn to toggle the landing bag deploy switch into the automatic position. If a light came on, reentry should take place while retaining the retro pack. Given the earlier questions about the landing bag switch, Glenn realized the controllers must have found a possible problem with a loose heat shield. The test was run but no light appeared. Glenn also reported there were no bumping noises during spacecraft maneuvers.
Mercury Control was still undecided on the course of action to take. Some controllers thought the
retrorocket
A retrorocket (short for ''retrograde rocket'') is a rocket engine providing thrust opposing the motion of a vehicle, thereby causing it to decelerate. They have mostly been used in spacecraft, with more limited use in short-runway aircraft land ...
pack should be jettisoned after retrofire, while other controllers thought the retro pack should be retained, as added assurance that the heat shield would stay in place. Mission Director Walter C. Williams decided to keep the retro pack in place during reentry, overruling Flight Director
Chris Kraft
Christopher Columbus Kraft Jr. (February 28, 1924 – July 22, 2019) was an American aerospace and NASA engineer who was instrumental in establishing the agency's Mission Control Center and shaping its organization and culture. His protégé ...
. Walter Schirra, the California communicator at Point Arguello, relayed the instructions to Glenn: the retro pack should be retained until the spacecraft was over the Texas tracking station. After the mission was over, the "Segment 51" warning light problem was later determined to be a faulty sensor switch, meaning that the heat shield and landing bag were in fact secure during reentry.
Glenn was now preparing for reentry. Retaining the retro package meant he would have to retract the periscope manually. He would also have to activate the 0.05-g sequence by pushing the override switch. ''Friendship 7'' neared the California coast. It had been four hours and 33 minutes since launch. The spacecraft was maneuvered into retrofire attitude and the first retrorocket fired. "Roger. Retros are firing. ... Are they ever. It feels like I'm going back toward Hawaii.", Glenn radioed. The second and then the third retros fired at five-second intervals. The spacecraft attitude was steady during retrofire. Six minutes after retrofire, Glenn maneuvered the spacecraft into a 14-degree nose up pitch attitude for reentry.
''Friendship 7'' lost altitude in its reentry glide over the continental United States, and headed toward splashdown in the Atlantic. The Texas tracking station told Glenn to retain the retro pack until the accelerometer read 1.5 ''g'' (14.7 m/s
2). Glenn reported as he crossed Cape Canaveral that he had been controlling the spacecraft manually and would use the fly-by-wire mode as a backup. Mercury Control then gave him the 0.05 ''g'' (0.49 m/s
2) mark, and he pressed the override button. About the same time, Glenn heard noises that sounded like "small things brushing against the capsule". "This is Friendship 7 – a real fireball outside," he radioed Mercury Control. A strap from the retro package broke partially loose and hung over the spacecraft window as it was consumed in the reentry plasma stream. The spacecraft control system was working well but the manual fuel supply was down to 15 percent. The peak of reentry deceleration was still to come. Glenn switched to fly-by-wire and the automatic tank supply. This combination had more available fuel.
The spacecraft now experienced peak reentry heating. Glenn later reported, "I thought the retro pack had jettisoned and saw chunks coming off and flying by the window." He feared the chunks were pieces of his heat shield that might be disintegrating. The chunks were pieces of the retro package breaking up in the reentry fireball.
After passing the peak ''g'' region, ''Friendship 7'' began oscillating severely. The astronaut could not control the ship manually. The spacecraft was oscillating past 10 degrees on both sides of the vertical zero-degree point. "I felt like a falling leaf," Glenn later said. He activated the auxiliary damping system, which helped to stabilize the large yaw and roll rates. Fuel in the automatic tanks was getting low. Glenn wondered if the spacecraft would retain stability until it was low enough to deploy the
drogue parachute
A drogue parachute is a parachute designed for deployment from a rapidly-moving object. It can be used for various purposes, such as to decrease speed, to provide control and stability, or as a pilot parachute to deploy a larger parachute. ...
.
The automatic fuel supply ran out at 1 minute and 51 seconds, and manual fuel ran out at 51 seconds, before drogue chute deployment. The oscillations resumed. At 35,000 feet (10 km), Glenn decided to deploy the drogue chute manually to regain attitude stability. Just before he reached the switch, the drogue chute opened automatically at 28,000 feet (8.5 km) instead of the programmed 21,000 feet (6.4 km). The spacecraft regained stability and Glenn reported, "everything was in good shape."
At 17,000 feet (5 km) the periscope opened and was available for the astronaut to use. Glenn tried to look out the overhead window instead, but it was coated with so much smoke and film that he could see very little. The spacecraft continued to descend on the drogue chute. The antenna section jettisoned and the main chute deployed and opened to its full diameter. Mercury Control reminded Glenn to manually deploy the landing bag. He toggled the switch and the green light confirmation came on. A "clunk" could be heard as the heat shield and landing bag dropped into place, four feet (1.2 m) below the capsule.
Splashdown
The spacecraft splashed down in the North Atlantic at coordinates near , short of the planned landing zone. Retrofire calculations had not taken into account spacecraft weight loss due to use of onboard consumables. , a destroyer code-named "Steelhead", had spotted the spacecraft when it was descending on its parachute. The destroyer was about away when it radioed Glenn that it would reach him shortly. ''Noa'' came alongside ''Friendship 7'' seventeen minutes later.
One crewman cleared the spacecraft antenna and another crewman attached a line to hoist ''Friendship 7'' aboard. After being pulled from the water, the spacecraft bumped against the side of the destroyer. Once ''Friendship 7'' was on deck, Glenn intended to leave the capsule through the upper hatch, but it was too hot in the spacecraft and Glenn decided to blow the side hatch instead. He told the ship's crew to stand clear and hit the hatch detonator plunger with the back of his hand. The detonator plunger recoiled, and slightly cut the astronaut's knuckles through his glove. With a loud bang, the hatch was off.
Harry Beal
Harry Beal (August 16, 1930 – January 26, 2021) was the first US Navy Seal.
Navy SEAL
Beal joined the U.S. Navy in 1948, first serving aboard the U.S.S. Shenandoah as a gunner's mate. He joined the underwater demolition team, the precursor t ...
, the first U.S Navy Seal, pulled Glenn out of ''Friendship 7''. A smiling Glenn got out of ''Friendship 7'' and stood on the deck of ''Noa''. His first words were, "It was hot in there."
The astronaut and spacecraft came through the mission in good shape.
"The Fourth Orbit"
After the return of ''Friendship 7'', NASA announced on April 19, 1962 that the spacecraft would be lent to the
United States Information Agency
The United States Information Agency (USIA), which operated from 1953 to 1999, was a United States agency devoted to "public diplomacy". In 1999, prior to the reorganization of intelligence agencies by President George W. Bush, President Bill C ...
for a world tour. The tour included more than 20 stops, becoming known as the "Fourth orbit of ''Friendship 7''".
Spacecraft location
Mercury spacecraft # 13 – ''Friendship 7'' – is currently displayed at the Steven F. Udvar-Hazy Center
National Air and Space Museum
The National Air and Space Museum of the Smithsonian Institution, also called the Air and Space Museum, is a museum in Washington, D.C., in the United States.
Established in 1946 as the National Air Museum, it opened its main building on the Nat ...
in Chantilly, VA.
Timeline and parameters
Launch
Flight
Parameters
*
Mass
Mass is an intrinsic property of a body. It was traditionally believed to be related to the quantity of matter in a physical body, until the discovery of the atom and particle physics. It was found that different atoms and different elementar ...
of spacecraft:
*
Perigee
An apsis (; ) is the farthest or nearest point in the orbit of a planetary body about its primary body. For example, the apsides of the Earth are called the aphelion and perihelion.
General description
There are two apsides in any ellip ...
of orbit:
*
Apogee
An apsis (; ) is the farthest or nearest point in the orbit of a planetary body about its primary body. For example, the apsides of the Earth are called the aphelion and perihelion.
General description
There are two apsides in any ellip ...
of orbit:
*
Inclination
Orbital inclination measures the tilt of an object's orbit around a celestial body. It is expressed as the angle between a Plane of reference, reference plane and the orbital plane or Axis of rotation, axis of direction of the orbiting object ...
of orbit: 32.5°
*
Orbital period
The orbital period (also revolution period) is the amount of time a given astronomical object takes to complete one orbit around another object. In astronomy, it usually applies to planets or asteroids orbiting the Sun, moons orbiting planets ...
: 88.5 min
Dramatization in film
Philip Kaufman
Philip Kaufman (born October 23, 1936) is an American film director and screenwriter who has directed fifteen films over a career spanning more than six decades. He has been described as a "maverick" and an "iconoclast," notable for his versati ...
's 1983 film
''The Right Stuff'' includes a dramatization of the ''Friendship 7'' mission in which
Ed Harris
Edward Allen Harris (born November 28, 1950) is an American actor and filmmaker. His performances in ''Apollo 13'' (1995), ''The Truman Show'' (1998), ''Pollock'' (2000), and '' The Hours'' (2002) earned him critical acclaim and Academy Award n ...
plays Glenn. The sequence depicts the spacecraft's three orbits and Glenn's responses to what he saw, sometimes quoted verbatim, as well as the concerns over the heat shield during reentry. The mysterious "fireflies" are also shown, but their true explanation is not revealed; instead they are depicted as magical protection summoned by
Australian Aborigines
Aboriginal Australians are the various Indigenous peoples of the Australian mainland and many of its islands, such as Tasmania, Fraser Island, Hinchinbrook Island, the Tiwi Islands, and Groote Eylandt, but excluding the Torres Strait Islands ...
at the
Muchea Tracking Station
Muchea Tracking Station was an Earth station in Australia located close to Muchea in the
Shire of Chittering, about north of Perth, Western Australia, built specifically for NASA's Project Mercury.
History
Muchea was established in 1960, a ...
.
The 2016 film ''
Hidden Figures
''Hidden Figures'' is a 2016 American biographical drama film directed by Theodore Melfi and written by Melfi and Allison Schroeder. It is loosely based on the 2016 non-fiction Hidden Figures (book), book of the same name by Margot Lee Shetterl ...
'' features the ''Friendship 7'' mission in the climax of the movie, focusing on
Katherine Johnson
Katherine Johnson (née Coleman; August 26, 1918 – February 24, 2020) was an American mathematician whose calculations of orbital mechanics as a NASA employee were critical to the success of the first and subsequent U.S. crewed spaceflights. ...
's calculations of the landing.
Anniversary commemoration
To commemorate the 50th anniversary of the flight in 2012, Glenn was surprised with the opportunity to speak with the
orbiting crew of the
International Space Station
The International Space Station (ISS) is the largest modular space station currently in low Earth orbit. It is a multinational collaborative project involving five participating space agencies: NASA (United States), Roscosmos (Russia), JAXA ...
while Glenn was on-stage with
NASA Administrator
The Administrator of the National Aeronautics and Space Administration is the highest-ranking official of NASA, the national space agency of the United States. The administrator is NASA's chief decision maker, responsible for providing clarity to ...
Charlie Bolden
Charles Frank Bolden Jr. (born August 19, 1946) is a former Administrator of NASA, a retired United States Marine Corps Major General, and a former astronaut who flew on four Space Shuttle missions.
He graduated from the United States Naval ...
at
Ohio State University
The Ohio State University, commonly called Ohio State or OSU, is a public land-grant research university in Columbus, Ohio. A member of the University System of Ohio, it has been ranked by major institutional rankings among the best publ ...
, where
the public affairs school is named in honor of Glenn.
See also
*
Devil's Cigarette Lighter
The Devil's Cigarette Lighter was a natural gas well fire at Gassi Touil in the Sahara Desert of Algeria. Ignited by static electricity when a pipe at the GT2 well ruptured on November 6, 1961, the Phillips Petroleum Company/OMNIREX/COPEFA-owned we ...
, a
gas well
An oil well is a drillhole boring in Earth that is designed to bring petroleum oil hydrocarbons to the surface. Usually some natural gas is released as associated petroleum gas along with the oil. A well that is designed to produce only gas m ...
fire reportedly seen from orbit by Glenn
*
Space capsule
A space capsule is an often-crewed spacecraft that uses a blunt-body reentry capsule to reenter the Earth's atmosphere without wings. Capsules are distinguished from other satellites primarily by the ability to survive reentry and return a payl ...
*
Space exploration
Space exploration is the use of astronomy and space technology to explore outer space. While the exploration of space is carried out mainly by astronomers with telescopes, its physical exploration though is conducted both by robotic spacec ...
*
Splashdown
Splashdown is the method of landing a spacecraft by parachute in a body of water. It was used by crewed American space capsules prior to the Space Shuttle program, by SpaceX Dragon and Dragon 2 capsules and by NASA's Orion Multipurpose Crew ...
*
U.S. space exploration history on U.S. stamps
Notes
References
External links
Mercury-Atlas 6 Radio Transcripts on spacelog.orgNASA Mercury MA6 press kit - Jan 21, 1962Results of the first U.S. crewed orbital space flight - Feb 20, 1962 (''Friendship 7'') NASA report - (PDF format)*
*
*
{{Orbital launches in 1962
Spacecraft launched in 1962
Human spaceflights
Project Mercury
John Glenn
Individual spacecraft in the collection of the Smithsonian Institution
Spacecraft which reentered in 1962
Articles containing video clips
Spacecraft launched by Atlas rockets