NASA Facts Project Mercury and Gemini 1967

8/7/2019 NASA Facts Project Mercury and Gemini 1967

1/12

N A S A ~ i l l ~ ~ AN EDUCATI ONAL PUBL IC ATION OF THE

NAT IONAL AER ONAUTICS AND SPACE AD MI NI STRATIONNF- 9/VOl. II . NO. 8

Manned Space Flight:PrOjects Mercury andGem iniMANNED SPACE FLIGHT

A major goal of the United States space programis manned flight to the moon and safe return toearth before the end of this decade.NASA's manned space fl ight program has beendivided into three steps or projects - Mercury,Gemini, and Apollo.Project Mercury put manned spacecraft into acontrolled earth orbit to investigate man's performance capabilities and his capacity to withstandthe environment of space and to test and success-

fully recover the vehicle.Project Gemini has fulfilled its original objectives; among them, extending orbital missions upto two weeks at a time and developing the techniques for orbital rendezvous and docking, in whichtwo space vehicles are maneuvered close togetherand finally joined.That same technique of orbital rendezvous - butaround the moon instead of earth - will enableastronauts in the three-man Apollo spacecraft toachieve lunar landi ngs.One- man Me rcury spacecraf t (foregrou nd ) al ongs ide two-man Gemini spacecraft.- ----,.----, ,,

~ _ _ a:: l W 0a: 0:r 0 WI - U I -- -


2/12

PROJECT MERCURYProject Mercury became an official program ofNASA on November 26, 1958. A Space Task Gro up(the forerunner of today's Manned SpacecraftCenter, Houston, Texas) was formed at the LangleyResearch Center, Hampton, Virginia. Seven astronauts were chosen in April 1959 after a nationwidecall for je t pilot volunteers.The one -man Mercury spacecraft was designedand built with a maximum' orbitin'g weight of about3,200 pounds. Shaped somewhat like a bell (truncated cone ), the craft was 74.5 inches wide acrossthe bottom and about 9 feet tall. The astronautescape tower on top added another 17 feet for anoverall length of approximately 26 feet at launch.Two boosters were chosen - the Army's Redstone(78,000 Ibs. thrust) and Air Force's Atlas (360,000

Ibs. thrust) - for suborbital and orbital flights, re-

Frogmen fi t a flotation collar to Mercury spacecraft afterits complet ion of an orb ital flight miss ion .2

spectively. Before the manned flights began,--Harn , 'the chimp, successfully achieved a suborb italMercury-Redstone 2 (MR - 2) flight on January 31,1961.Then all was ready for the historic MR-3 flightof May 5, 1961, as Astronaut Alan B. Shepard, Jr.,made the first U.S . manned space flight. His suborbital mission of 15 minutes took his Freedom 7spacecraft 116 miles high into space .After another countdown for MR-4 on July 21 ,1961, the Redstone booster hurled AstronautVirgil I. "Gus" Grissom through the second ballistic(suborbital) flight in the Liberty Bell 7.This ended the Redstone suborbital tests as theMercury-Atlas series of flights advanced 'to orbi talmissions. Before the first manned attempt anotherchimp, Enos , made an orbital flight (MA-5) onNovember 29, 1961.An MA- 6 space milestone, on February 20,

Atlas launches Mercury spacecraft.


3/12

- 1962; ' made Astronaut John H. Glenn, Jr., the firstAmerican in orbit, completing three circuits inFriendship 7.On the MA-7 mission of May 24, 1962, Astronaut M. Scott Carpenter in Aurora 7 completedanother three-orbit flight.

MA-8 of October 3, 1962, doubled the flighttime in space as Astronaut Walter M. Schirra, Jr.,orbited six times, landing Sigma 7 in the Pacificrecovery area, instead of the Atlantic.Finally, on May 15-16, 1963, Astronaut L. GordonCooper, Jr.'s, Faith 7 completed a 22-orbit missionof 341/2 hours, triumphantly concluding the flightphase of Project Mercury.Originally, Project Mercury was assigned onlytwo broad missions by NASA - first, to investigateman's ability to survive and perform in the spaceenvironment; and second, to develop the basicspace technology and hardware for manned spaceflight programs to come.Among the significant aerospace medical information derived from Mercury were: Consumption of food and beverages and sleeping during space flight were proved possible. Radiation dose received by the astronautswas considered medically insignificant. All measured physiological functions remainedwithin anticipated ranges throughout all flights.There was no significant degradation of pilot function attributable to space flight. There was no evidence of abnormal sensory,psychiatric, or psychological responses to spaceflight.The following were also accomplished in ProjectMercury: Development of a NASA management systemthat could carry out more advanced manned spaceflight ventures.

Exploration of the fundamenta Is of spacecraftreentry. Starting a family of launch vehicles from existing rockets that led to new booster designs. Setting up of an earth-girdling space trackingsystem that was later modified for the Gemini andApollo projects. Training of a pool of astronauts that could beaugmented to meet the requirements of futurespace exploration programs.PROJECT GEMINI

Project Gemini was named after the constellation Gemini (Twins).

NASA decided to follow the Mercury's basic"capsule" design for Gemini spacecraft, savingtime and engineering efforts. Bu t the two-man craftwas wider 00 feet), taller 09 feet), and more thantwice as heavy (8300 Ibs.). These dimensions provided 50 percent more cabin space, making roomfor much new equipment and with it far greaterperformance flexibility.Since Mercury's Redstone and Atlas boosterslacked the power to orbit the heavier two-man craft,a modified version of the military Titan II becamethe Gemini Launch Vehicle (GLV), with a ' totalthrust of 530,000 pounds (first stage, 430,000pounds). The hypergolic (self-igniting) propellantsused were non-explosive, an astronaut safety factor.Chosen for Gemin i's prime mission of orbitalrendezvous and docking wa s the Agena-D targetvehicle, a modified version of the reliable Agena-Bsecond stage that, with Thor or Atlas boosters,had orbited many satell ites and launched Marinerand Ranger probes. Agena's "stop-and-resta rt "rocket engine, capa ble of cu toff and reignition atleast four times, was important for maneuvers withGem ini. The hypergolic propellants are UDMH(unsymmetrical dimethylhydraz ine) and IRFNA (inhibited red fuming nitric acid).Agena-D is 32 feet long and 5 feet in diameterand shaped like a cylinder.GEMINI FLIGHT STATISTICS

From the first Gemini unmanned flight on April ,8, 1964, to the final manned flight ending November 15, 1966, Gemin i flight time totaled 974 hours,37 minutes, and 42 seconds. Of this, 969 hours,51 minutes, and 26 seconds were manned.The highest altitude reached by the mannedGemini spacecraft was 853 miles during theGemini XI mission. This se t a world's record.Orbital rendezvous was accomplished 10 times ;docking, 9 times. Docking, first accomplishedMarch 16, 1966, in the Gemini 8 experiment, isanother Gem in i first in space.Gemini astronauts spent a tota l of 12 hours 12minutes without the protecti on of their spacecraftin "space-walk" and other activities. In a gravitygradient experiment (See Gemini Experiments."),Gemini and Agena, linked by a taut tether, orbitedearth for over 4 hours in a station-keeping exerciseaimed at saving maneuvering fuel.GEMINI SPACECRAFT

The Gemini craft was designed to be piloted by3


4/12

Gem ini astronaut floa ts high above earth outside of his orbiting spacecraft.4


5/12

F REENTRY MODULE ~ ___ _

Separated segments of Gemini mock-up.

its two-man crew. After an automated launch, theGemini spacemen took over: turning, changingspeed, even shifting orbits.The spacecraft consists of two major portions-the reentry module and the adapter module. Thelatter, in turn, also has two separate sections, sothat Gemini, as launched, is actually a three-partstructure.Only the reentry module returned to earth. Thismodule contains the "living" quarters where thetwo astronauts ride.The life-supporting cabin is double-walled withan inner shell around the crew's pressurized compartment and an outer shell as the craft's externalhull.Between these shells is a storage space forelectronic gear and other apparatus - a technological improvement over the Mercury craft, whosecomponents (parts) were "stacked" upon one another inside the crowded pilot's compartment. Incontrast, much Gemini equipment was in thedouble-walled storage area, where it could be easily

checked, adjusted, replaced, even when Geminiwas in place atop Titan on the launch pad.The af t (rear) section contained more equipment,including the ablative (melting and evaporating)heat shield that protected the reentry module fromair-friction heat on earth return.One purpose of the two-part adapter module,which flares out from 7112 feet to 10 feet in diameter, was to "adapt" (fit) the narrow Gemini to theTitan booster's broad top. Secondly, the adapter'sgO-inch deep volume was another housing area for

equipment.The adapter retrograde section, adjacent to thecrew's reentry module, includes two sets of engines- retrorockets (for reducing speed) and spacemaneuvering thrusters.The adapter's equipment sect ion holds fuel cells,attitude controls, propellant tanks, oxygen supplies,electrical components, and a liquid-coolant radiator to dissipate internal spacecraft heat away intoopen space.The lower end of this two-part adapter is mated,

5


6/12

by means of a metal collar, to the top of the Titanlaunch rocket.EJECTION SEAT

Based on a jetplane technique, Gem in i's lightweight ejection seats could , in emergency, catapultthe astronauts out of two large hinged hatchesthat opened mechanically.Unlike Mercury's automatic ejection sensors,Gemini's system relied upon the astronaut crew'squick reflexes, because Titan's non-explosive propellants merely burn and allow time for humanreactions.COMPUTER

Among Gemini innovations was a "shoebox"computer, weighing only 57.6 Ibs. and occupying amere cubic foot of cabin space, yet able to makethe computations for the intricate r ~ n d e z v o u s anddocking maneuvers with the orbiting Agena-D.FUEL CELL

Another "space first" was Gemini's fuel cell generating electrical power by chemical reaction.Much lighter than the equivalent batteries theyreplace, two groups of fuel cells could provide1,000 watts each, supplying the spacecraft's totalelectrical needs.GUIDANCE SYSTEM

Aboard Gemini was an inertial guidance systemwhich records and totals every bi t of progressforwarq, backward, and sideways, from the earthlaunched starting point to the space destination.Linked into the guidance system during orbitalmaneuvers were other units - computer, radar,electronic controls, attitude thrusters, propulsionunits - so that the astronauts' master controlscould accurately achieve rendezvous and dockingwith Agena.RENDEZVOUS RADARGemini's high-definition radar gave the range(distance), bearing (direction and angle of approach), and closing speeds of the chase and targetvehicles, with data starting when they were 250miles apart.Later, the high-intensity flashes of Agena's lightbeacon became visible to the astronauts, at a maximum range of 50 miles. These optical observations, plus radar tracking, were then combined,6

as the astronauts manually guided Gemini towardrendezvous with Agena. -COMMUNICATIONS SYSTEMS

Gemini missions employed three major communications systems: voice, which included anintercom connection between the astronauts; thereceiver of command signals and updated orbitinformation from Mission Control Center; data collection tapes and their relay transmitters for automatic transmission of reports to earth.ENVIRONMENTAL CONTROL SYSTEM (ECS)

The Gemini environmental control system provided oxygen for astronaut breathing; eliminatedwaste such as exhaled carbon dioxide; cooled thespacecraft, its equipment, and the astronauts'space suits; and provided drinking water.Though the Gemini life-support system was similar to the Mercury ECS , major engineering changeswere made. Each astronaut had two parallel suitcircuits for oxygen, plus the option of using thecabin's habitable (purified) atmosphere while beingpartially unsuited for more freedom of action.Mercury's bottled gas was replaced in Gemini bya liquid oxygen supply, requiring less storagevolume for the maximum 14-day supp ly.The third major ECS change was an improvedmethod of dissipating unwanted heat into space.FOOD AND WATER

Besides being a body fuel, food is important toman as a psychological "uplift."A basic diet of 2,550 calories per man was fulfilled by freeze-dried foods including meats, soups,desserts, and fruits. Water restored the food to itsoriginal form.GEMINI lAUNCH VEHICLE

The Gemini launch vehicle was a modification ofthe military Titan II . Fueled with stable and storable propellants, it was 10 feet wide and 89 feetlong (first stage booster 70 feet). The combinedGemini-Titan stood 108 feet high.

An important Gemini launch vehicle system wasthe Malfunction Detection System, whose electronic monitors watched the vehicle's performanceduring launch for possible booster trouble. Warningsignals allowed ample time for the astronauts toabort (cut short) the mission, if necessary, byusing their ejection seats.


7/12

Gemini spacecraft is raised to top of gantry for mating with launch vehicle .7


8/12

The Agena D target vehicleas seen in space duringapproach of the Geminispacecraft. (above) .

Gemini launch vehiclerockets Gemini space-craft from Cape Ken-nedy, Fla. (right) .Atlas launches Agenatarget vehicle from CapeKennedy, Fla. (far right).

8


9/12

/ 'AGENA-D TARGET VEHICLEIn the docking of Agena-D and Gemini, the twospacecraft were joined nose to nose. Hence, afterfirst being orbited, the Agena was turned aroundso that its fore-end faced the nose of the upcomingGemini.At the Agena's forward end, the target dockingadapter (TDA) is a cylindrical collar, within whichis a docking cone illuminated by two approachlights. Self-adjusting mechanisms locked firmly tothe inserted nose of Gemini and moored the twovehicles.

STANDARDIZED SPACE LAUNCH VEHICLEHistorically famous as the booster for highlysuccessful Mercury space flights, the Atlas alsoserved as the Agena launch rocket in Gemini's ren

dezvous experiments.Known as the Standardized Space Launch Vehicle (SSLV), this 72-foot Atlas booster was poweredby conventional liquid rocket engines. Atlas poweralone cannot orbit the Agena , and at booster burnout, pyrotechnic devices (explosive bolts) at theSLV-adapter's forward end released the Agena,whose own engine fired to gain orbital velocity.PRE-LAUNCH CHECKOUTS

All the major vehicles arrived at Cape Kennedybroken down into modules and sections. Afterdozens of checkouts, all modules were mated intofull vehicles. The final tests included radio andradar circuits; stimulated flight via computer; simulated launch with the two astronauts aboard thespacecraft; servicing and fueling of Titan withcheckout of engine systems; complete check oftotal Gemini Titan equipment; 300-minute dressrehearsal countdown; final 2-day servicing andcheckout.Only after this long parade of cross-check checkouts did the real countdown start.Sharing in all main tests, the two Gemini astronauts gained confidence that the Titan booster andGemini spacecraft would bear them into orbit, andsafely return them to earth.The Mission Control Center at Cape Kennedymonitored the early Gemini flights. In later missions, the flight phase was monitored by the newMission Control Center at the Manned SpacecraftCenter, Houston, Texas, the launch phase stillbeing conducted by the Cape Kennedy team.

TRACKING NETWORKExpanded from the former Mercury network, theGemini tracking system comprised 13 land stationsand two tracking ships, the latter filling landlessgaps in the Pacific Ocean.Besides tracking equipment, all stations hadtwo-way communications with the Gemini spacecraft. Some had add itional telemetry equipment orcommand signal transmitters .

GEMINI RENDEZVOUS MISSIONA Gemini rendezvous mission generally called

for sending up the Agena target vehicle from CapeKennedy's launch Complex 14 prior to the Geminichase vehicle's lift-off from Launch Complex 19.The Agena was propelled in to a circular orbit185 miles up , after which precise velocity andtrajectory elements were ca lculated. Later Geminiblasted off, within the specified "launch window"- the time interval during which launch will produce an orbit permitting the two craft to meet.Gemini's orbit had to be in the same plane (slanttoward equator) as Age na's. This restricted theGemini launch window to about 2 hours in each 24-hour day during the 5-day period the target vehiclecould wait for rendezvous and docking. Certainorbit-correcting maneuvers by the Agena , beforeGemini launch, expanded the launch window.

The basic plan was to maneuver the Gemini intoa circular orbit whose altitude was less than theAgena. The Gemini , traveling a shorter distance,would catch up with the Agena.TARGET CAPTURE

When the distance between vehicles was 250miles radar was switched on. As the gap closedto 50 miles, the Gemini astronauts picked up theAgena's flashing beacon and took over control ofGemini.Aiding the astronauts was the status displaypanel outwardly mounted on the Agena-D, givingvisual data on Agena fuel reserves, electricalpower, and attitude position.During rendezvous maneuvers the relative speedbetween the vehicles was cut to less than 2 mph,so that when docking, their noses touched gently.On contact, the Gemini's narrow end entered theAgena's target docking adapter, whose latchesclamped shut to preven t the two vehicles fromslipping apart. Then a motorized Agena unit pulledthe Gemini inward.

9


10/12

Photograph of Red Sea and Gulf of Aden area snappedfrom Gemini XI spacecraft about 540 miles above earth .Once the two craft were tightly moored, matching electrical contacts met and gave the Geminiastronauts direct control of Agena's onboard equipment - guidance, propulsion, attitude control, relay

switches, and the rest.Union of the two vehicles results in a Gemini /Agena spacecraft almost 50 feet long and muchmore versatile. The rocket power provided byAgena allowed for flights to higher altitudes or tochange orbital plane.REENTRY AND RECOVERY

Their maneuvers completed, the astronauts unhooked their Gemini craft from the Agena (left inorbit) and prepared for earth-return. The Geminireturned to earth under guidance of the spacecraftcomputer, or under astronaut control.Because of Gemini's slight "lift" (gliding ability),there is a capability for guiding the spacecrafttoward the desired landing site.Gemini spacecraft also had large parachutes forwater landings, as did Mercury.ASTRONAUT SELECTION

High physical , mental, and academic standardsare among the criteria for selection of astronauts.As of March 1967, NASA had selected a total of55 astronauts, of which 47 were still active. An-other group is to be added later in 1967.Astronauts are chosen on two bases: as pilotastronauts and scientist-astronauts. The pilotastronaut must have at least 1000 hours of jetflyi ng experience. The scientist-astrona ut has tohave a doctorate or the equivalent in experiencein the natural sciences, medicine, or engineeringHe must meet the physical and psychological10

Gemini astronauts practiced docking with the Agena inthis simulator at Lang ley Research Center, Hampton, Va.standards required of pilots. After appointment, thescientist-astronaut is trained to fly high-performance helicopters and jet planes.ASTRONAUT TRAIN ING

All astronauts are trained to reach peak mentaland physical efficiency for Gemini flights. Basicscience studies were expanded to include suchcourses as computer fundamentals, guidance technology, and astrogation (space navigation).To prepare for space missions, astronauts practiced earth-simulated fl ights in trainers. Throughthe use of such simulators, astronauts learned theelements of rendezvous and docking by mean..s of

electronic dials and dummy controls.One Gemini mission simulator was located atthe Manned Spacecraft Center's Clear Lake site atHouston, Texas, where the Mission Control Centeris also located. Another simulator installation wasat Cape Kennedy, Florida.Centrifuges at Johnsville, Pennsylvania, and atAmes Research Center in California provided high-gloads to match the stresses of powered launches,training astronauts to handle controls despite acceleration stra ins.GEMINI EXPER IMENTS

Gemini astronauts carried out a large number ofscientific, technical , and engineering experiments.The information derived from these experi mentsadds up to a considerable increase in spaceknowledge.Astronauts took photographs from their orbi t ingspacecraft of the zodiacal light - a disk of lightaround the sun which cannot be seen from earth .They took ultra-violet pictures of stars. Ultra-


11/12

4 ' .violE:tt radiation from stars tells much about theirphysical and chemical compositions. Such radiation is cut off from earth observatories by theatmosphere.

They took photographs of earth and its cloudcover, providing a new wea lth of information forgeographers, meteorologists, and oceanographers.Their photographs indicated that sensing from orbitmay be a good way to locate and observe earth'sresources: water, minerals, oil, and others. A newatlas is based on photographs of earth taken by theastronauts during Gemini flights.Micrometeoroid and radiation experiments carried out during Gemini flights have increased

understanding of what to expect from these spacephenomena.The gravity-gradient experiment, in which Geminiand Agena were stabilized at opposite ends of a

100-foot-long tether, has important implicationsfor operation of future manned stations in earthorbit.

The performance and physical conditions of theastronauts have shown that, in periods of at least

The Agena target vehicle secured by a tether to theGemini XII spacecraft, part of which can be seen inforeground.

two weeks, there are no deterioration of an astronaut's visual acuity, no noticeable changes in behavior, and no abnormality in vestibular, metabolic,digestive, or respi ratory functions.Gemini experiments validated life-support techniques, equipment, and concepts for future spacemissions. They suggested that man can safely conduct operations in space for as long as 30 days.

DEFINITIONSAPOGEE : In an orbit about the earth , the point atwhich the satellite is farthest from the earth; thehighest altitude reached.ASTRONAUTICS: The art, skill , or activity of operating space vehicles. In a broader sense, thescience of space flight.ATTITUDE: The position or orientation of an aircraft, spacecraft, etc ., either in motion or at rest,as determined by the relationship between its axesand some reference line or plane such as thehorizon.BALLISTIC TRAJECTORY: The trajectory followedby a body being acted upon only by gravitationalforces and the resistance of the medium throughwhich it passes.BOOSTER ROCKET: A rocket engine, either solid orliquid fuel, that assists the normal propulsive system or sustainer engine of a rocket or aeronauticalvehicle in some phase of its flight. A rocket usedto set a missile vehicle in motion before anotherengine tak es over.DOCKING: The process of bringing two spacecrafttogether while in space.EVA (Extra-Vehicular Ac ti vity) : Any activity performed by astronauts outside of the protective confines of their spacecraft.HYPERGOLlC: Propellants, fuel and oxidizer, whichignite spontaneously upon contact. Hydrazine andnitrogen tetroxide are examples.MODULE: A self-contained unit of a launch vehicleor spacecraft which serves as a building block forthe overall structure. The module is usually designated by its primary function as command modulelunar module, etc. A one-package assembly offunctionally associated electronic parts, usually aplug-in unit.PERIGEE: That orbital point nearest the earth whenthe earth is the center of attraction.PITCH: The movement of an aircraft or spacecraftabout its lateral (nose going up or down) axis.PROPELLANT: Any agent used for consumption orcombustion in a rocket and from which the rocket

11


12/12

derives its thrust, such as a fuel , oxid izer, additive,catalyst, or any compound or mixture of these.REACTION ENGINE: An engine that develops thrustby its reaction to ejection of a substance from it;specifically, such an engine that ejects a jet orstream of gases created by the burning of fuelwithin the engine.REENTRY: The event occurring when a spacecraftor other object comes back into the sensible atmosphere after being rocketed to altitudes above thesensible atmosphere; the action involved in thisevent.RETROROCKET: A rocket fitted on or in a spacecraft, sate II ite, or the like to prod uce thrust opposed to forward motion.ROLL: The rotational or oscillatory movement ofan aircraft or similar body which takes place abouta longitudinal axis through the body - called "roll"for any amount of such rotation.

SENSOR: The component of an instrument ~ : h a t . ~ converts an input signal into a quantity which ismeasured by another part of the instrument. Alsocalled "se nsing element."SUBORBITAL: Non-orbiting or ballistic flight trajectory from launch point to target point.TRAJECTORY: In general, the path traced by anybody, as a rocket, moving as a result of externallyapplied forces.WEIGHTLESSNESS: A condition in which no acceleration, whether of gravity or other force, can bedetected by an observer within the system in question. A condition in which gravitationa l and otherexternal forces acting on a body produce no stress,either external or internal, in the body.YAW: The latera I rotationa I or osci lIatory movement of an aircraft, rocket, or the like about atransverse axis. The amount of this movement, i.e.,the angle of yaw.

GEMINI MISSION BOX SCOREMission Crew Dates Duration Revolutions Objectives Accomplished(Hrs:min :sec)Gemini I Apr. 8-12, 1964 Tracked for three Check spacecraft / launch vehicle structural compatibility andorbits only. aerodynamic performance.Gemini II Jan. 19, 1965 18:16 suborbital Systems performan ce and heat shield reentry test.Gemini III Griss om-Young Mar . 23, 1965 4:52:31 3 Spacecraft systems and crew compatibility.Gemini IV McDivittWhite June 3-7, 1965 97:56:12 62 Demonst rate spacecraft systems and crew capability for fourdays: 81A for 20 minutes.Gemini V CooperConrad Aug. 21-29, 1965 190:55:14 120 Demonstrate longdurationdezvous maneuvers. flight, rendezvous radar and ren-Gemini VII Borman-Lovell Dec. 4-18, 1965 330:35:01 206 2-week duration , shirtsleeve environment, rendezvous vehicle forGemini VI, controlled reentry . .Gemini VI Schirra Dec. 15-16, 1965 25:51 :24 16 Ontime launch procedures, closed-loop rendezvou s, statio n keep-Stafford ing with Gem ini VII.Gemini VIII Armstrong- Mar. 16, 1966 10:41 :26 6.6 Demonst rated rendezvous and docking with Agena, mUltiple AgenaScott restart in orbit, controlled landing, emergency recovery (missionterminated early because of control system electrical short).Gemin i IX Stafford-Cernan June 3-6, 1966 72:20:50 45 Demonstrate three rendezvous techniques, EVA (2 hrs ., 7 min.),with detailed work tasks, precisionplanned landing point). landing (0.38 nm fromGemin i X YoungCollins July 1821, 1966 70:46:39 43 Dual rendezvous using Agena propulsion for docked maneuvers,retrieval of experiment package from Agena during 92 minutesof 81A: demonstrated feasibility of using onboard navigation forrendezvous.Gemini XI Conrad-Gordon Sept. 12-15, 1966 71:17:08 44 Firstorbit reridezvous and docking with Agena, 853 statute milesapogee using Agena propulsion, 167 minutes total 81A, tetherexercise , automatic reentry.Gemini XII Love II-AIdri n Nov. 11-15, 1966 94:34:31 59 Three 81A's total of 5 hours, 26 minutes, gravitygradient tetherexercise, rendezvous and docking with Agena , rendezvous withsola r eclipse.

NASA FACTS IS AN EDUCATIONAL PUBLICATION OF NASA'S OFFICE OF PUBLIC AFFAIRS, EDU CATIONAL PROGRAMS DIVISION.A MAILING LIST IS MAINTAINED FOR FREE DISTRIB UTION TO TEACH ERS; TO REQUEST LISTING FOR NASA FACTS WRITETO PUBLICATIONS DISTRIBUTION , FAD-I, NATIONAL AERONAUTICS AN D SPACE ADMINISTRATION, WASHINGTO N, D.C. 20 546.For Sale by the Super intendent of Documents, U.S. Gove rn m ent Printing Off ice , Wash ington, D.C. 20402 . Pr ice 15 cents

u.s. GOVER NM ENT PRINTING OFFICE : 19670-272-0 17

Date post:	08-Apr-2018
Category:	Documents
Upload:	bob-andrepont
View:	223 times
Download:	1 times