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GLENN CARPENTER GRISSOM SCHIRRA SHEPHERD COOPER SLAYTON

  MERCURY THE JOURNEY BEGINS

Project mercury propels forward the serious mission for regular and effcient space flights that would have manned crew leading space travel that would ultimately land a man on the moon. Mercury should be hailed as a heroic period in space history where men put their lives into the hands of a vast technical crew made up from the best in the world. It states simply that through diligence , percerverence and an element of bravado goals can be achieved. The years 1959-1963 would shape the future of manned space flight.

We shall see that these historical flights enthralled the world that this was not just a dream  but a reality that was happening in their lifetime. The early sixties hailed great change for the Americans, a new enthusiastic President with Kennedy at the helm predicting a man on the moon by the end of the decade, the Russian space program had begun wth success with Satellites and Yuri Gagarin being propelled into the heavans via a Vostok rocket. Yes! this really was the decade of politicians sanctioning huge amounts of monies to a project that was truly untested, training highly rated pilots to become skilled Astronauts to a level never achieved before, and competing against Russia. But was this an arrogant space race at no cost? No, I do not think so! This was America pushing forward technology, getting a Nation enthused, after dark times with Korea, and later Vietnam. This was America displaying its power to the world through a decade of programs that would push forward the advancement of technology we take for granted today. They used to their advantage chosen Astronauts known as the ‘Mercury Seven’ in a massive publicity campaign that would warm the hearts of most Americans, whilst captivating the imaginations of people around the globe.

Without Mercury, without dedicated scientists and ground crew, without highly skilled Astronauts, without taxpayers money for this project there would never have been a Lunar Landing in 1969 !

Early Flight Tests

There were many test flights to test  the Mercury project before it was manned, these were:

Little Joe 1  Big Joe 1  Little Joe 6  Little Joe 1A  Little Joe 2  Little Joe 1B  Beach Abort   Mercury-Atlas 1 Little Joe 5 Mercury-Redstone 1  Mercury-Redstone 1A  Mercury-Redstone 2   Mercury-Atlas 2  Little Joe 5A   Mercury-BD Mercury-Atlas 3   Little Joe 5B   Mercury-Atlas 4 Mercury-Scout 1   Mercury-Atlas 5 ..

A sample from these flights are given below 

Mission: Little Joe 1
Vehicle: Little Joe (1)
Crew: Unmanned
Dates: September 15th 1959

Mission Purpose:
This was the Max Q abort and escape test. Flight was to determine how well the escape rocket would function under the most severe dynamic loading conditions anticipated during a Mercury-Atlas launching. 
Orbit:
Distance: .5 statute miles
There was an evacuation of the area 35 minutes before, then the  batteries for the programmer and destruct system in the test booster were being charged. However , half an hour before launchtime, an unexpected explosive flash occured. Afterwards it was evident that only the capsule-and-tower combination had been launched, on a trajectory similar to an off-the-pad abort. Near apogee, at about 2000 ft, the clamping ring that held tower to capsule released and the little pyro-rocket for jettisoning the tower fired. The accident report for LJ-1, issued September 18, 1959, blamed the premature firing on the Grand Central escape rocket on an electrical leak, or what missile engineers call transients or ghost voltages in a relay circuit. The fault was found in a coil designed to protect biological specimens from too rapid an abort.

 

Launch Pad: LC-14 Vehicle: Atlas (1) Crew: Unmanned

 Dates: July 29th 1960

Payload: Spacecraft number 4, Launch Vehicle 50-D

Mission Purpose:  To qualify spacecraft and Atlas combination including specfic tests which were:
Recover the capsule , determine the structral integrity of the Mercury capsule structure and afterbody shingles under the maximum heating conditions which could be encountered from an orbital launch . Also check the Mercury capsule afterbody heading rates for the all important re-entry. The flight dynamics of re-entry were tested as well as checks on the capsule recovery involving personnel. The flight was categorised as a failure, however safety, technology and methods were being developed on each mission.
 Orbit:
Altitude: 8.1 statute miles
Orbits: 0

 

Mission: Mercury-Atlas 5
Launch Pad: LC-14
Vehicle: Atlas (5)
Crew: Enos the chimp

Payload: Spacecraft number 9, Launch Vehicle number 93-D

Mission Purpose: Primate test of Environmental Control System in Orbit. They had an on board visitor during the flight who was a chimpanzee called Enoz.He held up well to cabin pressure and flight time of nearly 90 minutes.

Orbit:
Altitude: 147.4 apogee by 99.5 perigee statute miles
Orbits: 2
Period: 88 minutes, 26 seconds
Duration: 0 Days, 3 hours, 20 minutes, 59 seconds
Distance: 50,892 statute miles

MANNED FLIGHTS 1961-1963

  

FREEDOM 7

Dates: 5th May 1961
 
Crew: Alan B. Shepard Jnr

Miles Travelled: 116.5

Orbits: Nil

Duration: 15 minutes 28 seconds.

Mission Purpose: Carrying the first American into space (Alan Shepherd) and a payload of the launch Vehicle MR7
The main scientific objective of project Mercury was to determine man’s capabilities in a space environment and in those environments to which he will be subject upon going into and returning from space. A  very full mission which  had its objectives including : The development of an automatic escape system, vehicle control during insertion, behavior of space systems, evaluation of pilots capabilities in space, in flight monitoring, retrofire and reentry maneuvers and landing and recovery. Above all though it had to prove man’s capabilities in a space environment and in those environments to which he will be subject upon going into and returning from space. The mission ironed out a few problems with maneuverbility, capsule and landing whilst catapulting Alan Shepherd into World-Wide stardom. Later he would walk on the Moon as part of Apollo 14.

(For Alan Shepherds Profile see Apollo 14 autograph colection)

  

LIBERTY BELL 7

Dates: July 21st 1961

Crew: Virgil I. Grissom

Miles Travelled: 302 miles

Duration: 15 minutes 37 seconds

Orbits: Nil

Mission Objective:
After  earlier delays the mighty Mercury-Redstone 4 was the fourth mission in the Mercury-Redstone series of flight tests and the second U.S. manned suborbital spaceflight. The main objective was to corroborate the man-in-space concept. The main configuration differences between the MR-3 spacecraft was that it contained a  large viewing window and an explosively actuated side hatch.The large viewing window was actually a result of a change requested by Mercury astronauts. By doing this it was obvious that this would allow the astronauts to have a greater viewing area than the original side port windows. The field of view was 30 degrees in the horizontal plane and 33 degrees in the vertical. The explosively actuated side hatch was used for the first time on the MR-4 flight.  

Gus Grissom lay in the spacecraft 3 hours and 22 minutes prior to after extensive tests for weather conditions, launch procedures up to 21 days were spent at the launch pad itself. Everything had to be correct in order for the pad procedures to initiate the power to ignite such a vast sized rocket, any error could potentially be fatal, so delays were for safety and checks. During the boosted phase of flight, the flight-path angle was controlled by the launch-vehicle control system. Launch-vehicle cutoff occurred at T+2 minutes 23 seconds, at which time the escape tower was released by firing the escape and tower jettison rockets, an incredible picture of sheer power and thrust giving you the impression that ir would seem impossible to launch such a Rocket. In flight the periscope was extended; the automatic stabilization and control system provided 5 seconds of rate damping, followed by spacecraft turnaround. It then oriented the spacecraft to orbit attitude of -34 degrees.There was a Retro sequence was initiated by timer at T+4 minutes 46 seconds, which was 30 seconds prior to the spacecraft reaching its apogee. Gus Grissom took control of the spacecraft attitude at T+3 minutes 5 seconds and controlled the spacecraft by the manual proportional control system to T+5 minutes 43 seconds. He initiated firing of the retrorockets at T+5 minutes 10 seconds. From T+5 minutes 43 seconds, he controlled the spacecraft by the manual rate command system through reentry. The retrorocket package was jettisoned at T+6 minutes 7 seconds. The drogue parachute was deployed at T+9 minutes 41 seconds, and main parachute, at T+10 minutes 14 seconds.Although the flight was successful the spacecraft was lost during the post landing recovery period as a result of premature actuation of the explosively actuated side egress hatch. The capsule actually sank in 15,000 feet of water in the Atlantic ocean shortly after splashdown. The astronaut egressed from the spacecraft immediately after hatch actuation and was retrieved after being in the water for about 3 to 4 minutes. Mercury missions were making ground and now regularly Astronauts were being tested for future Lunar missions, Grissom would have been one of them.

(For Gus Grissoms biography see Astronaut Autograph collection)

  

FRIENDSHIP 7

Dates: February 20th 1962

Crew: John H Glenn

Miles Travelled: 75,679

Orbits: 3

Duration:  4 hours 55 mins and 23 seconds

Mission Purpose: Simply to place a man into Earth orbit and  observe his reactions to the space environment and safely return him to Earth to a point where he could be readily found. During this  Mercury flight it was planned during the first orbit was to maintain optimum spacecraft attitude for radar tracking and communication checks.  After failed pre test checks  this flight launched off with John Glenn in the capsule having a total weightless time of 4 hours 48 minutes.
During the flight only two major problems were encountered: (1) a yaw attitude control jet apparently clogged at the end of the first orbit, forcing the astronaut to abandon the automatic control system for the manual-electrical fly-by-wire system; and (2) a faulty switch in the heat shield circuit indicated that the clamp holding the shield had been prematurely released Nevertheless the mission was successful and John Glenn was the first man to orbit the earth, and complete a total of 3 orbits.
(for John Glenns biography see Astronaut autograph collection )

  

AURORA 7

Dates: May 24th 1962

Crew: Scott M Carpenter

Miles Travelled: 99.9

Duration: 4 hours 56 minutes asnd 5 seconds

 Orbits: 3

Mission Purpose : To Corroborate man in orbit after an exceptionally good launch. During this mission the Spacecraft overshot intended target area by 250 nautical miles and  Carpenter reported a severe list angle on the order of 60 degrees from vertical and post flight photographs of the spacecraft taken after egress indicated approximately a 45 degree list angle, plus on return considerable amount of sea water was found in the spacecraft which was believed to have entered through the small pressure bulkhead when Carpenter passed through the recovery compartment into the life raft. However the main highlights showed total weightless time of nearly 4 hours and 40 minutes.The craft performed well and all main objectives were achieved.Equipment included for the flight provided valuable scientific information; notably that regarding liquid behavior in a weightless state. An experiment  also  was carried out to provide atmospheric drag and color visibility data in space through deployment of an inflatable sphere was partially successful. What this flight did achieve was to demonstrate  evidence for progressing into missions of extended durations which would have to be achieved in later Gemini and Apollo missions. 
(for Scott Carpenters biography see Astronaut Autograph section)

  

SIGMA 7

Dates: October 3rd 1962

Crew: Walter M Schirra

Miles Travelled: 143,983

Duration: 9 hours 13 minutes and 11 seconds

Orbits:6

Mission Purpose: To achieve a Manned mission in orbit for 9 hours. Astronaut Wally Schirra made six orbits of the Earth in the Sigma 7  spacecraft on October 3 1962, in an almost completely successful nine-hour flight focused primarily on technical evaluation rather than on scientific experimentation. This was to be was the longes American orbital flight yet achieved, but was still well behind the several-day record set by the Soviet Vostok 3 earlier in the year, and helped confirm the Mercury spacecraft’s long-duration capabilities in preparation for the one-day Mercury Atlas 9 mission which fwas planned for launch in 1963, and to be the last of the Mercury missions.

The mission finally launched on the morning of October 3, having been delayed two weeks due to problems with the Atlas. There were no significant technical problems during the flight and the spacecraft’s control systems were thoroughly checked out, and it was left to orbit in both automated and entirely passive flight modes for prolonged periods whilst the pilot monitored it and carried out some minor scientific experiments. After six successful orbits, the capsule landed in the Pacific Ocean where Astronaut Wally Schirra was picked and reported an overall successful mission which would lead confidently on to the final mission of Mercury

 

FAITH 7

Dates: May 15th 1963

Crew:Gordon Cooper Jnr Miles Travelled: 546,167Duration: 1 day 10 hours 19 minutes and 49 seconds.Mission Purpose: To complete a minimum manned 1 day mission in orbit.Faith 7 the last Mercury project mission rocket was launched from Launch Complex and is described as follows: 14. At T+ 60-seconds, the Atlas started its pitch program. Shortly afterward, MA-9 passed through Max-Q. At T+ 2-minutes and 14-seconds Cooper felt BECO (Booster Engine Cutoff) and staging. The two Atlas booster engines had been left behind. The Launch Escape Tower was then jettisoned. At T+ 3-minutes the cabin pressure sealed at 5.5 psi (38 kPa). Cooper reported, “Faith 7 is all go.”At about T+ 5-minutes was SECO (Sustainer Engine Cutoff) and Faith 7 entered orbit at 17,547 mile/h (7,844 m/s). After the spacecraft separated and turned around to orbit attitude, Cooper watched his Atlas booster lag behind and tumble for about eight minutes. Over Zanzibar on the first orbit, he learned that the orbital parameters were good enough for at least 20 orbits. As the spacecraft passed over Guaymas, Mexico still on the first orbit, capsule communicator Gus Grissom told Cooper the ground computers said he was “go for seven orbits”.At the start of the third orbit, Cooper checked his list of 11 experiments that were on his schedule. His first task was to eject a six-inch (152 mm) diameter sphere, equipped with xenon strobe lights from the nose of the spacecraft. This experiment was designed to test his ability to spot and track a flashing beacon in orbit. At T+ 3-hours 25-minutes, Cooper flipped the switch and heard and felt the beacon detach from the spacecraft. He tried to see the flashing light in the approaching dusk and on the nightside pass, but failed to do so. On the fourth orbit, he did spot the beacon and saw it pulsing. Cooper reported to Scott Carpenter on Kauai, Hawaii, “I was with the little rascal all night.” He also spotted the beacon on his fifth and sixth orbits.Also on the sixth orbit, at about T+ 9-hours, Cooper set up cameras, adjusted the spacecraft attitude and set switches to deploy a tethered balloon from the nose of the spacecraft. It was a 30-inch (762 mm) PET film balloon painted fluorescent orange, inflated with nitrogen and attached to a 100 feet (30 m) nylon line from the antenna canister. A strain gauge in the antenna canister would measure differences in atmospheric drag between the 100 miles (160 km) perigee and the 160 miles (260 km) apogee. Cooper tried several times to eject the balloon, but it failed to eject.Cooper passed Schirra’s orbital record on the seventh orbit while he was engaged in radiation experiments. After T+ 10-hours, the Zanzibar tracking station informed Cooper the flight was a go for 17 orbits. Cooper was orbiting the earth every 88-minutes 45-seconds at an inclination of 32.55 degrees to the equator.His scheduled rest period was during orbits 9 through 13. He had a dinner of powdered roast beef mush and some water, took pictures of Asia and reported the spacecraft condition. Cooper was not sleepy and during orbit 9 took some of the best photos made during his flight. He took pictures of the Tibetan highlands and of the Himalayas.

Controversy arose during the flight when Cooper reported that he could see roads, rivers, small villages, and even individual houses if the lighting and background conditions were right. This was later confirmed by the two-man Gemini crews that later flew (of which Cooper was included). Cooper slept intermittently the next six hours, during orbits 10 through 13. He woke from time to time and took more pictures, taped status reports and kept adjusting his spacesuit temperature control which kept getting too hot or too cold.

On his fourteenth orbit, Cooper took an assessment of the spacecraft condition. The oxygen supply was sufficient. The peroxide fuel for attitude control was 69 percent in the automatic tank and 95 percent in the manual one. On the fifteenth orbit, he spent most of the time calibrating equipment and synchronizing clocks. When he entered night on the sixteenth orbit, Cooper pitched the spacecraft to slowly follow the plane of the ecliptic. Through the spacecraft window he viewed the zodiacal light and night airglow layer. He took pictures of these two “dim light” phenomena from Zanzibar, across the Earth’s nightside, to Canton Island. The pictures were later found to have been overexposed, but they still contained valuable data.

At the start of the 17th orbit while crossing Cape Canaveral, Florida, Cooper broadcast slow scan black and white television pictures to the ground. The picture showed a ghostly image of the astronaut. In the murky picture, a helmet and hoses could be seen, it was the first time an American astronaut had sent back television images from space.

On the 17th and 18th orbits, he took infrared weather photos and moonset Earth-limb pictures. He also resumed Geiger counter measurements of radiation. He sang during orbits 18 and 19, and marveled at the greenery of Earth. It was nearing T+ 30-hours since liftoff.

On the nineteenth orbit, the first sign of trouble appeared when the spacecraft 0.05 g (0.5 m/s²) light came on. However, this turned out to be a faulty indicator, and the spacecraft was not reentering. On the 20th orbit, Cooper lost all attitude readings. The 21st orbit saw a short-circuit occur in the bus bar serving the 250 volt main inverter. This left the automatic stabilization and control system without electric power.

On the 21st orbit, John Glenn onboard the Coastal Sentry Quebec near Kyūshū, Japan, helped Cooper prepare a revised checklist for retrofire. Due to the system malfunctions, many of the steps would have to be done manually. Only Hawaii and Zanzibar were in radio range on this last orbit, but communications were good. Cooper noted that the carbon dioxide level was rising in the cabin and in his spacesuit. He told Carpenter as he passed over Zanzibar, “Things are beginning to stack up a little.” Throughout the problems, Cooper remained cool, calm and collected. At the end of the 21st orbit, Cooper again contacted Glenn on the Coastal Sentry Quebec. He reported the spacecraft was in retro attitude and holding manually. The checklist was complete. Glenn gave a ten-second countdown to retrofire. Cooper kept the spacecraft aligned at a 34 degree pitchdown angle and manually fired the retrorockets on “Mark!”.

Fifteen minutes later the Faith 7 landed just four miles (6 km) from the prime recovery ship, the carrier USS Kearsarge. This was the most accurate landing to date, despite the lack of automatic controls. The landing spot was just 130 km south east of Midway Island, in the Pacific Ocean. Splashdown was at T+ 34-hours 19-minutes 49-seconds after liftoff. The spacecraft tipped over in the water momentarily, then righted itself. Helicopters dropped rescue swimmers and relayed Cooper’s request of an Air Force officer, for permission to be hoisted aboard the Navy’s carrier. Permission was granted, 40 minutes later the explosive hatch blew open on the deck of the Kearsarge. Cooper stepped out of the Faith 7 to a warm greeting. (Source of this full account is by Wikepedia)

Cooper thus concluded an amazing series of unmanned and manned flights (26) since 1959 drawing it to a successful conclusion which would lead the US space program confidently into project Gemini.

(For Gordon Coopers biography see Astronaut Autograph collection)

  GEMINI PROGRAM THE QUEST FOR THE MOON CONTINUES

 

After the general success of the Mercury program throughout the early 1960’s publich awareness and confidence had grown sufficient for NASA’s goal of putting a man on the moon by the end of the 60’s decade. American men had out the lives on the line for the ulitimate quest of being selected for the Lunar mission. It would still be six years before Armstrong would step down from the Lunar Module, and that would mean a lot more intense testing, Astronaut training , technology development, and of course a budget that would probably laughed out of the Senate in todays terms.

All to often we read about the heroic missions of the Apollo moon landing programs ,whilst in reality we must pay homage to all of those people involved in the pre Apollo programs that paved the way. Without a vast budget, a dedicated ground crew, test pilots, ground breaking scientists, technicians , administration staff and public support would we have ever seen Kennedys’ prophesy come to pass.

Gemini Goals

A specific goal was in place for the following:

To subject two men and their equipment to long duration flights for future deeper space missions ie (The Moon)

To be able to rendevous and dock with other crafts in orbit, and to maneuver those vehicles in space using the propulsion system of the target vehicle for such maneuevers.

To perfect methods of re-entry and landing the spacecraft at a pre-selected land-landing point.

To gain additional information concerning weightlessness on crew members, and to record the physiological reactions of crew members.

GEMINI MISSIONS

  

Gemini 3

Dates: 23rd March 1965

Crew: John Young  and Virgil ‘Gus’ Grissom

Mission Purpose: Gemini 3 became the first crewed Earth-orbiting spacecraft of the Gemini series. It was piloted both by experienced astronauts Virgil “Gus” Grissom and John Young. Their main objective was to demonstrate the crewed qualifications of the Gemini spacecraft including evaluation of the two-man Gemini design, the worldwide tracking network, the orbit attitude and maneuver system (OAMS), the control of reentry flight path and landing point, spacecraft systems, and spacecraft recovery.

Further to those very crucial tests they had objectives that included evaluation of flight crew equipment and effects of low level launch vehicle oscillations (POGO) on the crew, performance of three experimants, and to obtain photographic coverage from orbit.

After successful tests the Astronauts splashed down in the Atlantic in the vicinity of Grand Turk Island, at 22.43 that same day. Due to less-than-expected spacecraft lift during reentry, the spacecraft landed 111 km short of the target point.It was reported that both astronauts became seasick, removed their suits, and left the spacecraft at about 3:00 p.m. EST. They were picked up by helicopter and  were found to be in good condition. The Gemini capsule was recovered at 5:03 p.m. EST. Two of the three experiments were performed successfully, the third, sea urchin egg growth in zero-G, was not due to a mechanical failure. The photography objective was only partially achieved because of an improper lens on the 16 mm camera. All other mission objectives were achieved.

    

Gemini 4

Dates:  3rd June - June 7th 1965

Crew: James Mc divitt and Edward White

Mission Purpose: Gemini 4 was the second crewed mission of the Gemini series and was flown by James McDivitt and Edward White on a 4-day, 62-orbit mission. The mission had a major highlight which was the first American spacewalk, carried out by Ed White.

Mission objective as to test the performance of the astronauts and capsule and to evaluate work procedures, schedules, and flight planning for an extended length of time in space. Secondary objectives carried out were extraavehicular activity in space, conduct stationkeeping and rendezvous maneuvers, evaluate spacecraft systems, demonstrate the capability to make significant in-plane and out-of-plane maneuvers and use of the maneuvering system as a backup reentry system, and conduct 11 experiments. 

During there flight time the orbit was raised to 166 x 290 km during the first revolution to attempt a rendezvous with the second stage. This station-keeping exercise was cancelled early in the second revolution after a large depletion of 42% of the fuel, it was determined that use of more fuel would jeopardize other mission objectives. It was after this that Ed White got into special gear and pressurized his suit at 3.7 psi. McDivitt depressurized the cabin, bringing the pressure to zero at 2:33:35 p.m. EST, and the hatch was opened at 2:34. Ed White stood up two minutes later and exited the spacecraft using a hand-held gas gun at 2:46 to become the first American to walk in space. White was attached to the spacecraft by only an 8 meter tether. The gas gun fuel supply was depleted in 3 minutes, after which White pulled on the tether and twisted his body to maneuver around the spacecraft. The extravehicular activity (EVA) lasted 23 minutes, after which White pulled himself back into the spacecraft. An incredible fete for its time, and not for the faint hearted.

There was difficulty sealing the hatch, but working together the astronauts finally closed it, at 3:10 p.m. EST. Cabin repressurization began at 3:12:50. Drifting flight was maintained for the next 30 hours to conserve propellant. At 11:56:00 a.m. EST on June 7. Gemini 4 splashed down . The crew were recovered by helicopter and flown to the aircraft carrier U.S.S. Wasp at 1:09 p.m. and the capsule was recovered at 2:28 p.m.

  

Gemini 5

Dates: August 21st- August 29th 1965

Crew: Gordon Cooper and Charles ‘Pete’ Conrad

Mission Purpose: Gemini 5, carrying astronauts Gordon Cooper and Charles “Pete” Conrad was the third crewed Earth-orbiting spacecraft of the Gemini series. The flight was designed to last eight days and test rendezvous procedures. Again the major objectives of this mission were to demonstrate a long-duration crewed flight, evaluate the effects of long periods of weightlessness on the crew, and test rendezvous capabilities and maneuvers using a rendezvous evaluation pod.

Further objectives included demonstration of all phases of guidance and control systems which would support the rendezvous and controlled reentry guidance as well as to evaluate the fuel cell power system and rendezvous radar. Lastly they were to test the capability of either pilot to maneuver the spacecraft in orbit to close proximity with another object, and to conduct 17 given experiments during their mission. 

There were four rendevous tests to perform ,however on day 5 thruster number 7 became inoperative with the naneuvering system also becoming hard to handle. Later thruster 8 failed and there was limited experimental and operational activities due to the erratic behaviour of the equipment. Splashdown was successful , however it overshot by 169 kilometeres.

      

Gemini 7 (manned) Gemini 6A (manned)

Dates: December 4th -December 18th

Crew:James Lovell and Frank Borman (Gemini 7)Tom Stafford and Wally Schirra (Gemini 6A)

Mission Purpose: Gemini 6A and 7 was the fourth crewed Earth-orbiting spacecraft of the Gemini series, and was  launched before Gemini 6A.  Gemini 7  carried astronauts Frank Borman and Jim Lovell on their 14 day mission. Its mission priorities were as follows

 (1) to demonstrate a 2-week flight,

 (2) to perform stationkeeping with the Gemini launch vehicle stage 2,

(3) to evaluate the ’shirt sleeve’ environment and the lightweight pressure suit,

(4) to act as a rendezvous target for Gemini 6A

(5) to demonstrate controlled reentry close to the target landing point.

The crew members had three scientific, four technological, four spacecraft, and eight medical experiments to perform. A very full mission with the added task of working with a post flight launch of Gemini 6A .Immediately after separation Gemini 7 began station-keeping operations with the Titan II second stage at distances from 6 meters to 80 km over a period of 17 minutes. On the third revolution the perigee was raised to 230 km to ensure an orbital lifetime of 15 days which was required to successfully complete their mission.

On 6 December, 45 hours into the mission, Lovell removed his spacesuit to evaluate the shirtsleeve environment. The first five days were spent conducting experiments and spacecraft tests. On 9 December the orbit was circularized to 299.7 x 303.7 to prepare for the rendezvous exercise with Gemini 6A. On 10 December after neaely 5 days into the mission Lovell put his suit back on and Borman removed his. Some 20 hours later Lovell removed his suit as well and both astronauts operated without suits for the remainder of the mission except for the rendezvous with Gemini 6A and reentry.

Experiments were conducted over the next few days, then on 15 December Gemini 6A was launched. Gemini 6A caught up to Gemini 7 and rendezvous was technically achieved and station-keeping begun on 15 December at 2:33 p.m. EST with the two Gemini spacecraft in zero relative motion at a distance of 110 meters. These Station-keeping maneuvers involving the spacecraft circling each other and approaching and backing off continued for 5 hours 19 minutes over three and a half orbits. During the maneuvers, all four astronauts on both spacecraft took turns in the formation flying activities and photographs were taken from both spacecraft. This marked the first time two spacecraft were maneuvered with respect to each other by their crews. At the end of stationkeeping Gemini 6A fired thrusters to move to a position roughly 50 km away from Gemini 7 for drifting flight during the sleep period. Gemini 6A returned to Earth on December 16. Gemini 7 remained in Earth orbit and reentered two days later.

Splashdown followed at 9:05:04 in the western Atlantic southwest of Bermuda and the spacecraft successfully recovered. Total mission elapsed time was 330:35:01, making this the longest anyone had ever stayed in space.NASA announced that the astronauts were pronounced in “better than expected” physical condition after their two week flight.

   

GEMINI 8

Dates: 16 March 1966

Crew: Neil Armstrong and David Scott

Mission Purpose: Gemini 8 was the sixth crewed Earth-orbiting spacecraft of the Gemini series, carrying astronauts Neil Armstrong and David Scott. The main mission objectives were to perform rendezvous and four docking tests with the Agena target vehicle and to execute an ExtraVehicular Activity (EVA) experiment. Other objectives included parking the Agena in a 410 km circular orbit, performing a rerendezvous with the Agena, conduct systems evaluation, evaluating the auxiliary tape memory unit, and demonstration of controlled reentry. Ten technological, medical, and scientific experiments were carried on board.

Gemini 8 was launched on the 16 March 1966 and over the next six hours the spacecraft performed 9 maneuvers in order that it could rendezvous with the Gemini Agena Target Vehicle (GATV), which had been launched previously (at 9:00 a.m. EST). The rendezvous phase ended at 4:39 p.m. EST, with the spacecraft only 45 meters apart with zero relative motion. The usual station-keeping and other maneuvers were performed for about half an hour, and then Gemini 8 moved in and docked with the GATV on the 5th revolution at 5:14 p.m. This was the first docking ever to take place in space, and something Armstrong was to prove successful on with his control techniques for the future moon landing.

About 27 minutes after docking at 5:41 p.m. the combined vehicle began to go into a violent yaw and tumble. Armstrong disengaged the Gemini capsule from the GATV causing it to roll, pitch, and yaw even more rapidly than when it was connected to the GATV, approaching and possibly exceeding a rate of one revolution per second. Armstrong and Scott managed to deactivate the OAMS and in a final attempt to counteract the violent tumbling all 16 reentry control system (RCS) thrusters were utilized to damp out the roll.

This manuever was successful in stabilizing the spacecraft at 6:06:30 p.m. but ended up using a lot of the fuel (75%). It was then discovered that one of the 25-pound Orbit Atitude and Maneuver System (OAMS) roll thrusters (roll thruster no. on Gemini 8 had been firing continuously, causing the tumbling. Apparently it had short-circuited while being used to maneuver the Gemini-GATV combination and had stuck open. Because of the premature use of the reentry control system an immediate landing was required by Gemini safety rules, so  unfortunately the planned EVA and other activities were cancelled. Retrofire took place on the 7th revolution at 9:45:49 p.m. on 16 March, just over 10 hours after launch, and the spacecraft splashed down in the western Pacific Ocean about 800 km west of Okinawa at 25.22 N, 136.00 E, 2 km from the target.  Total mission elapsed time was only 10:41:26.

Though the termination of the mission precluded achievement of many mission objectives, the rendezvous and docking was accomplished, as was the evaluation of the auxiliary tape memory unit and demonstration of controlled reentry. Of the six scientific experiments only the Agena micrometeorite collection was successful.

 

GEMINI 9A

Dates: June 3rd - June 6th 1966

Crew: Tom Stafford and Eugene Cernan

Mission Purpose: Gemini 9A was the seventh crewed Earth-orbiting spacecraft of the Gemini series and astronauts Tom Stafford and Gene Cernan were on board with these objectives:

 (1) rendezvous techniques and docking with a target vehicle to simulate manuevers to be carried out on future Apollo missions,

(2) an ExtraVehicular Activity (EVA) spacewalk to test the Astronaut Maneuvering Unit (AMU), and

(3) precision landing capability. Scientific objectives included obtaining zodiacal light and airglow horizon photographs. Two micrometeorite studies were to be carried out, and there were also one medical and two technological experiments.

After a postponement was postponed Gemini 9A was launched on 3 June at 8:39:33 a.m. EST (13:39:33.335 UT) and inserted into a 158.8 x 266.9 km orbit. After three orbital maneuvers they were within 8 meters of the ATDA. As it was confirmed that the launch shroud on the ATDA had failed to action and was blocking the docking port the flight plan was then revised to include two equiperiod passive rerendezvous maneuvers in place of the docking.

On 5 June at 10:02 a.m. EST the Gemini capsule was depressurized and the hatch above Cernan opened.Astronaut Cernan was externally out of the spacecraft at 10:19 being attached by an 8 meter long tether which was connected to Gemini’s oxygen supply.Cernan retrieved the micrometeorite impact detector attached to the side of the capsule and then moved about the spacecraft. He had great difficulty manuevering and maintaining orientation on the long tether. Whilst outside Cernan took photographs of Gemini from the full length of the tether and finally moved to the back of the capsule where the Astronaut Maneuvering Unit (AMU) was mounted. He was scheduled to put on the AMU, disconnect from the Gemini oxygen supply (although he would still be attached to the spacecraft with a longer, thinner tether) and move to 45 meters from the capsule. The system of  getting into  the AMU took nearly five times more work than anticipated which overwhelmed  Cernan’s environmental control system and causing his faceplate to fog up resulting in poor visability..

It was also discovered that the AMU radio transmissions were distorted and because of this  Stafford insisted Cernan  was to return to the spacecraft. Cernan re-entered the spacecraft at 12:05 p.m. and the hatch was closed at 12:10. Cernan was the third person to walk in space and his total time of 2 hours, 8 minutes was the longest spacewalk yet.

Retrofire occurred at the end of the 45th revolution on 6 June at 8:26:17 a.m and splashdown was at 9:00:23 in the western Atlantic at under 10 kilometers from target.

(For Eugene Cernan and Tom Staffords biographies see Astronaut Autograph Collection)

   

GEMINI 10

Dates: July 18th -July 21st 1966

Crew:John Young and Michael Collins

Mission Purpose: Gemini 10 was the eighth crewed Earth-orbiting spacecraft of the Gemini series, with astronauts John Young and Michael Collins. Its main objective purpose was to conduct rendezvous and docking tests with the Agena target vehicle. The mission also  included a rendezvous with the Gemini 8 Agena target, two extravehicular activity (EVA) excursions, and the performance of 15 scientific, technological, and medical experiments. These scientific experiments were related to  the following (1) zodiacal light, synoptic terrain, and synoptic weather photography, (2) micrometeorite collections, (3) UV astronomical camera, (4) ion wake measurements, and (5) meteoroid erosion.

Gemini 10 was launched on 18 July from Complex 19 at 5:20:26 p.m. EST . At orbit insertion Gemini 10 was about 1600 km behind the Gemini Agena Target Vehicle 10 (GATV-10) which had been launched into a near circular orbit about 100 minutes earlier. Rendezvous with GATV-10 was achieved on the 4th revolution at 10:43 p.m. and at 11:13:03 p.m. docking was achieved. Due to an out-of-plane error in the initial orbit required the Gemini to use 60% of its fuel for the rendezvous, this was over twice the planned amount. To conserve fuel, Gemini 10 remained docked to GATV-10 for the next 39 hours and used the GATV propulsion system for maneuvers. The planned docking practice runs were cancelled.

A 14-second burn of the GATV-10 primary propulsion system was used to raise the dual spacecraft apogee to 764 km. While the spacecraft were docked, a bending mode test was conducted to study spacecraft dynamics and other experiments were performed. Another burn of GATV-10 at 3:58 p.m. on 19 July brought the spacecraft into the same orbit as the GATV-8, which had been launched on 16 March for the Gemini 8 mission. At 4:44 p.m. the Gemini cabin pressure was reduced to zero and the hatch was opened.

Collins stood up in his seat 3 minutes later and began photographing stellar UV radiation. Partway into the standup EVA Young and Collins began to experience severe eye irritation from an unidentified source and Young ordered termination of the EVA. Collins sat down and the hatch was closed at 5:33 p.m., and a high oxygen flow rate was used to purge the environmental control system.

Gemini 10 separated from GATV-10 at 2:00 p.m. EST on 20 July. A series of manuevers using its own thrusters brought Gemini 10 within about 15 meters of GATV-8. At 6:01 p.m. (48:41 ground elapsed time) the cabin was evacuated and the hatch opened for Collins to begin his second EVA. Collins left the spacecraft 6 minutes later attached to an umbilical cord and travelled to the GATV-8. Despite difficulties due to lack of handholds on the target vehicle Collins removed the fairing and retrieved the micrometeoroid detection equipment. During the EVA he lost his camera. He also retrieved the micrometeorite experiment mounted on the Gemini 10 spacecraft, but this apparently floated out of the hatch and was lost when Collins reentered the capsule.

The EVA was limited to 25 minutes of outside activity this was  due to lack of fuel. Collins reentered the capsule at 6:32 p.m. and the hatch was closed at 6:40. The hatch was reopened again at 7:53 p.m. to jettison 12 items before reentry. After about three hours of stationkeeping Gemini 10 moved away from GATV-8. At 8:59 p.m. the crew performed an anomaly adjust maneuver to minimize reentry dispersions resulting from the retrofire maneuver.

Retrorocket ignition took place during the 43rd revolution on 21 July at 3:30:50 p.m. EST and splashdown occurred at 4:07:05 p.m. in the western Atlantic at 26.74 N, 71.95 W, 875 km east of Cape Kennedy and 6.3 km from the target point. The crew was picked up by helicopter.

    

GEMINI 11

Dates: September 6th -September 15th 1966

Crew: Charles ‘Pete’ Conrad and Richard Gordon

Mission Purpose: Gemini 11 was the ninth crewed Earth-orbiting spacecraft of the Gemini series, and carried astronauts Charles “Pete” Conrad and Richard Gordon, both who went on to serve with Apollo moon missions.The 3-day mission was designed to achieve a first orbit rendezvous and docking with the Agena target vehicle, to accomplish two ExtraVehicular Activity (EVA) tests, to perform docking practice, docked configuration maneuvers, tethered operations, parking of the Agena target vehicle and demonstrate an automatic reentry. This was almost bringing to an end the era of Gemini to make way for Apollo 1 in 1967.

Further to the main priorities there were also eight scientific and four technological experiments on board. The scientific experiments were (1) synergistic effect of zero-g and radiation on white blood cells, (2) synoptic terrain photography, (3) synoptic weather photography, (4) nuclear emulsions, (5) airglow horizon photography, (6) UV astronomical photography, (7) Gemini ion wake measurement, and (8) dim sky photography.

Gemini 11 was launched on 12 September 1966 at 9:42:26 a.m. EST and inserted into a 160.5 x 279.1 km Earth orbit at 9:48:28. There were spacecraft maneuvers made to rendezvous with the Gemini Agena Target Vehicle 11 (GATV-11) at 11:07 a.m.  The GATV-11 had been previously launched 90 minutes before Gemini 11. Docking was completed at 11:16 a.m. on the first orbit, consuming less fuel than expected. Both Conrad and Gordon then conducted two docking exercises with the GATV, and then a maneuver at 2:14:14 p.m. brought the docked spacecraft into a 287 x 304 km orbit. The sleep period was spent in docked configuration.

On 13 September at 9:44 a.m the Gemini cabin atmosphere was evacuated and the hatch opened to begin Richard Gordon’s scheduled 107 minute EVA. He was  attached by an umbilical cord. Gordon set up a movie camera and retrieved the micrometeorite experiment. The next task, detaching one end of the 30 meter tether from the Agena and attaching it to the Gemini spacecraft docking bar, proved to be exhausting and overstressed Gordon’s life support system. After attaching the tether, Gordon stopped to rest astride the GATV, but due to the heavy perspiration inside the suit blurred his vision and even eventually blinded his right eye.

Conrad ordered him to cancel operations and return to the cabin. Gordon returned to the cabin at about 10:12 a.m. and closed the hatch at 10:17 a.m. so the cabin could be repressurized. At 11:19 a.m. the hatch was opened again to jettison some excess equipment. There followed a sleep period, the Agena primary propulsion system was fired for 25 seconds at 2:12:41 a.m. EST on 14 September, raising the docked spacecraft apogee to 1374.1 km. (this was a record altitude for an astronaut mission that would stand until Apollo 8 went to the Moon.)

After two orbits the Agena was fired again for 22.5. Gordon opened his hatch to begin a 2 hour 8 minute standup EVA during which he conducted photographic experiments. The hatch was closed at 9:57 a.m. and shortly afterwards the spacecraft were undocked and Gemini 11 moved to the end of the 30 meter tether attaching the two spacecraft. At 11:55 a.m. Conrad started a slow rotation of the Gemini capsule about the GATV which kept the tether taut and the spacecraft a constant distance apart at the ends of the tether. Oscillations occurred initially, but damped out after about 20 minutes. The rotation rate was then increased, oscillations again occurred but damped out and the combination stabilised. Gemini 11,  demonstated for the the first time  artificial gravity in space. After about three hours the tether was released and the spacecraft moved apart. A fuel cell stack failed at 4:13 p.m., but the remaining stacks took over the load satisfactorally. At 4:22 a.m. on 15 September a final rerendezvous maneuver without use of the rendezvous radar, which had malfunctioned, was accomplished.

Retrofire occurred at the end of the 44th revolution at 8:24:03 a.m. EST on 15 September and lead to eventual splashdown in the western Atlantic at 24.25 N, 70.00 W, 4.9 km from the target point, occurred at 8:59:35 a.m. EST. a.m. Total mission time was 71:17:08. A successful mission where all primary objectives were accomplished, and the last rerendezvous added to the mission plan due to the favorable fuel supply.

(For Pete Conrad and Richard Gordons’ biographies please see Astronaut Autograph Collection)

 

Gemini 12

Dates: November 11-November 15th 1966

Crew:James Lovell and Buzz Aldrin

Mission Purpose.. This was to be the last Gemini flight and the 10th mission achieved. The crew chosen were astronauts Jim Lovell and Edwin “Buzz” Aldrin, and their task was to perform rendezvous and docking with the Agena target vehicle, to conduct three ExtraVehicular Activity (EVA) operations, to conduct a tethered stationkeeping exercise, to perform docked maneuvers using the Agena propulsion system to change orbit, and demonstrate an automatic reentry. There were  a number of scientific, medical, and technological experiments on board totalling 14.

Gemini 12 was launched from Complex 19 on 11 November 1966 at 3:46:33 p.m. EST and inserted into a 160.8 x 270.6 km Earth orbit at 3:52:40. At 7:32 p.m. rendezvous was achieved with the Gemini Agena Target Vehicle (GATV), which had been launched 90 minutes before Gemini 12. Docking with the GATV was accomplished 28 minutes later, at 4:14 ground elapsed time (GET) on the third orbit, relying heavily on visual sightings due to problems with the onboard radar.

During insertion of the GATV into orbit they noticed a problem in the primary propulsion system, so the plan to use the GATV to lift the docked spacecraft into a higher orbit was abandoned. Instead two phasing maneuvers using the GATV secondary propulsion system were accomplished, and this  to allowed the spacecraft to rendezvous with the November 12 total eclipse over South America at about 9:20 a.m. EST with the crew taking pictures through the spacecraft windows.

The first standup EVA took place with the hatch opening at 11:15 a.m. EST (19:29 GET) on 12 November with Buzz Aldrin standing on his seat with his upper body out of the hatch. The EVA lasted 2 hours 29 minutes during which Aldrin mounted a camera to the side of the spacecraft collecting a micrometeorite experiment, with the hatch closing at 1:44 p.m. On 13 November at 7:16 a.m. the crew reported little or no thrust was available from two of the maneuvering thrusters. At 10:34 a.m. (42:48 GET) the hatch was opened for the second EVA. Aldrin was outside the spacecraft at 10:38, attached to a 9 meter umbilical cord. Firstly he worked in the hatch and nose area, and then moved along a handrail he had installed to the adapter section where he used foot restraints and tethers to position himself in front of a work panel mounted on the rear of the adaptor where he performed 17 relatively simple manual tasks. He then moved to the target vehicle adapter area and carried out another series of tasks, including use of a torque wrench while tethered. During this EVA he attached a 30 meter long tether stowed in the GATV adapter to the Gemini adapter bar. A  dozen two-minute rest periods were scheduled during the EVA to prevent Aldrin from becoming overtaxed as we have seen happen to previous spacewalkers. Aldrin reentered the capsule at 12:33 p.m. and closed the hatch at 12:40 p.m. It was reported that all tasks were accomplished and total EVA time was 2 hours 6 minutes.

At 3:09 p.m. Gemini 12 undocked from the GATV, moved to the end of the tether connecting the two vehicles, and began the tether experiment by moving in a cicular orbit about the GATV. The tether tended to remain slack, but the crew believed the two craft slowly attained gravity-gradient stabilization. The tether was released at 7:37 p.m. On 14 November the hatch was opened at 9:52 a.m. (66:06 GET) and Aldrin began the second standup EVA .This EVA included photography, additional experiments and the jettison of unused equipment. The EVA ended after 55 minutes when the hatch was closed at 10:47 a.m. Minor fuel cell and thruster problems were reported, but did not affect the remainder of the mission.

The automatically controlled reentry sequence began with retrofire at the end of revolution 59 on 15 November at 1:46:31 p.m. EST with Splashdown occurring at 2:21:04 p.m. in the western Atlantic. The crew was picked up by helicopter and brought aboard the U.S.S. Wasp at 2:49 p.m., the spacecraft was picked up at 3:28 p.m. Total mission elapsed time was 94:34:31. During this mission  scientific experiments that were successfully achieved were  (1) frog egg growth under zero-g, (2) synoptic terrain photography, (3) synoptic weather photography, (4) nuclear emulsions, (5) airglow horizon photography, (6) UV astronomical photography, and (7) dim sky photography. Two micrometeorite collection experiments, as well as three space phenomena photography experiments, were not fully completed.

(For Jim Lovell and Buzz Aldrins’ biographies please see Astronaut Autograph Collection)

And so we see the end of a long period oftest flights for the Gemini missions with te majority of objectives and experiments successful. Certain Astronauts were later selected for the Moon missions, these Astronauts were: Pete Conrad, James Lovell, Richard Gordon, Michael Collins, Neil Armstrong, Buzz Aldrin, Cene Cernan, John Young and Dave Scott. Out of these: Conrad, Armstrong, Aldrin, Cernan, Young and Scott would walk on the surface of the moon between 1969 and 1972.

THE RUSSIAN SPACE PROGRAM

 

America’s main  competition in particular during the 1960’s space race to the Lunar surface were the Soviets. They were already well advanced in projecting Satellites into outer Orbit after success with Sputnik 1. There history gives us a fascinating insight into a Nation determined to win the Cold war that was going on between themselves and the USA.For them it would incorporated a roller coaster ride of both success and tragedy,much of which would probably still not be known to a space enthused public. We must however salute there remarkable achievement of placing the first human (Yuri Gagarin into space and successfully bringing him back again

Soviet Space journey

It is know surprise that the Soviet military have had a great deal of authority in their progra. What was  once a world-wide superpower engulfed in secrecy and often in proproganda competition with the USA, the Soviet Union set an early ‘Pace for Space’. Their manned or scientific space missions could be justified if seen to be in co-operation with the mighty military presence. They say that it was actually as little as 20% Soviet launches which were considered for ‘national prestige’ purposes , namely (civilian manned flights, scientific and planetary).

Working to both five and ten year projects we see that their first such plan was approved in 1961, with setbacks along the way due to USA Star Wars program of events around 1985. Russian space historians variously refer to three or four generations of space systems, resulting in some confusion.

Way back between 1950 to 1960 were the very first serious studies for spacecraft and launch vehicles were actually taking place in 1956. There were three projects that were agreed for development: the ISZ first earth satellite (we know that this was launched as Sputnik-3); the Zenit photo-reconnaissance satellite; and the Vostok first manned spacecraft. Vostok is probably their most historically reknown spacecraft that was developed.

After much hype and propoganda surrounding  the first Sputnik in 1957 there then took place a real plan to develop both rockets and satellites necessary for the first probes of the Moon, and much deeper into space with Mars, and Venus. These would be developed long term as space launchers and spacecraft. Their known ambitious plans for manned expeditions no doubt sparked of the USA program into getting a man on the Moon first. Had it not been for some significant set backs they may have made it. The beginning of the 1960’s saw an amazing total of thirty space systems that actually, which with intervention by the Military this was reduced greatly. 

There were Military research programs from 1962 to 1964 code-named Shchit (space systems), Osnova (space equipment), and Ediniy KIK (ground systems) which mapped out the first generation of Soviet operational space systems which were deployed from1966-1975.

Soviet military objective was to integrate space forces into overall military planning, taking into account the most cost-effective use of resources.In 1970 were projects Prognoz and Sirius Phase I. and there was the development of the first nine systems of the second generation, these were completed in 1974-1975 with space flight trials carried out in the second half of the 1970’s. This lead on to the second group of  these second generation systems being developed in the second half of the 1970’s being actually deployed in the first half of the 1980’s. Soviet space history tells us that from 1971-1976 a total of 14 new space systems entered military service, and 16 were in operation. This was indeed a huge commitment, and that commitment is shown clearly today with what was the MIR space station and now working together on the International Space Station (ISS) as a space community. 

Moving forward with the third generation projects (1985 to 1990) these space systems constituted an integrated Multi-Element Space System, including interestingly the planned Multi-echelon Anti Ballistic Missile System. We see already that military rather than science was shaping the program at that time. However in 1985 these plans were cut back and rationalised to a condensed programme which would meet the American Strategic Defence Initiative challenge during what was by then their 12th Five Year Plan (1986-1990).

   

Of course in 1991 with  the break-up of the Soviet Union caused the launch site for the largest launch vehicles and the main planned launch vehicle producer being outside of Russia. That gives a very brief look at the Russian program, but it is right to provide a separate account of the MIR space station which is given below:

 

MIR

We have been familiar with the MIR space station for some years now and seen its develop grow into a very useable multi function works station. The word Mir  actually means “Peace” and “community” in Russian. with this space station contributing to world peace by way  hosting international scientists and American astronauts. Its purpose is to continually and successfully support a community of humans in orbit and symbolized the commonwealth of the Russian people.

Mir was a huge project which resulted in the construction of it taking place in orbit achieved by connecting different modules,. These modules were launched separately during a period from 1986 to 1996. It was good timing that the United States Shuttle program was by the well developed and able to combine its capabilities with MIR.. The orbiting Mir provided a large and livable scientific laboratory in space. The space shuttle missions would thus visit providing transportation and supplies creating history’s largest spacecraft, with a combined mass of 250 tons.

The view from a shuttle widow woud have been superb when in sight of the 100-ton Mir as it was as vast in size eclipsing by far the length of an average football pitch. Inside was apparently pretty cramped  as it had to hold everyday requirements for long stays. as well as scientific instruments and complicated equipment for research. Designed to house a comfotable 3 crew members it sometimes had to accomodate up to six for periods of a month up until It commonly housed three crewmembers, but it sometimes supported as many as six, for up to a ceasing in 1999. Its final journey was in 2001 after 15 years it re-entered the Earths atmosphere destined for the Pacific ocean.