Agena Target Vehicle
Encyclopedia
Spacecraft
A spacecraft or spaceship is a craft or machine designed for spaceflight. Spacecraft are used for a variety of purposes, including communications, earth observation, meteorology, navigation, planetary exploration and transportation of humans and cargo....
used by NASA
NASA
The National Aeronautics and Space Administration is the agency of the United States government that is responsible for the nation's civilian space program and for aeronautics and aerospace research...
during its Gemini program
Project Gemini
Project Gemini was the second human spaceflight program of NASA, the civilian space agency of the United States government. Project Gemini was conducted between projects Mercury and Apollo, with ten manned flights occurring in 1965 and 1966....
to develop and practice orbital space rendezvous
Space rendezvous
A space rendezvous is an orbital maneuver during which two spacecraft, one of which is often a space station, arrive at the same orbit and approach to a very close distance . Rendezvous requires a precise match of the orbital velocities of the two spacecraft, allowing them to remain at a constant...
and docking techniques and to perform large orbital changes, in preparation for the Apollo program lunar missions.
Operations
Each ATV consisted of an Agena-D derivative upper rocket stage built by LockheedLockheed Corporation
The Lockheed Corporation was an American aerospace company. Lockheed was founded in 1912 and later merged with Martin Marietta to form Lockheed Martin in 1995.-Origins:...
and a docking adapter built by McDonnell. The Agena was launched from Cape Canaveral Air Force Station Launch Complex 14
Cape Canaveral Air Force Station Launch Complex 14
Launch Complex 14 is a launch site at Cape Canaveral Air Force Station, Florida. LC-14 was used for various manned and unmanned Atlas launches, including the Friendship 7 flight aboard which John Glenn became the first American to orbit the Earth....
on top of an Atlas
Atlas-Agena
The Atlas-Agena was an American expendable launch system derived from the SM-65 Atlas missile. It was a member of the Atlas family of rockets, and was used for 119 orbital launches between 1960 and 1978....
booster built by the Convair division of General Dynamics
General Dynamics
General Dynamics Corporation is a U.S. defense conglomerate formed by mergers and divestitures, and as of 2008 it is the fifth largest defense contractor in the world. Its headquarters are in West Falls Church , unincorporated Fairfax County, Virginia, in the Falls Church area.The company has...
. The Agena first burn would occur shortly after shroud jettison and separation from the Atlas over the Atlantic Ocean
Atlantic Ocean
The Atlantic Ocean is the second-largest of the world's oceanic divisions. With a total area of about , it covers approximately 20% of the Earth's surface and about 26% of its water surface area...
. Over Ascension Island
Ascension Island
Ascension Island is an isolated volcanic island in the equatorial waters of the South Atlantic Ocean, around from the coast of Africa and from the coast of South America, which is roughly midway between the horn of South America and Africa...
, a second burn would place the Agena into a low circular orbit.
The McDonnell Gemini spacecraft would then be launched from Launch Complex 19
Cape Canaveral Air Force Station Launch Complex 19
Launch Complex 19 is a deactivated launch site on Cape Canaveral Air Force Station, Florida used by NASA to launch all of the Gemini manned spaceflights. It was also used by unmanned Titan I and Titan II launch vehicles....
, as soon as 90 minutes later. Both countdowns would proceed in parallel and required close synchronization. The Gemini would rendezvous and dock with the Agena as soon as Gemini's first orbit toward the end of the program.
The Gemini astronauts would then fly the combined spacecraft in a stabilized mode and perform a number of experiments:
- Using the Agena's attitude control system to stabilize the combination, which saved the Gemini's propellants
- Extra-vehicular activityExtra-vehicular activityExtra-vehicular activity is work done by an astronaut away from the Earth, and outside of a spacecraft. The term most commonly applies to an EVA made outside a craft orbiting Earth , but also applies to an EVA made on the surface of the Moon...
to perform practice work on a tool panel. This required installing handrails on later flights to prevent excessive astronaut exertion. - Refiring the Agena engine to raise the spacecraft's apogee. Gemini 11Gemini 11Gemini 11 was the ninth manned spaceflight mission of NASA's Project Gemini, which flew from September 12 to 15, 1966. It was the 17th manned American flight and the 25th spaceflight to that time . Astronauts Charles "Pete" Conrad, Jr. and Richard F. Gordon, Jr...
reached a record of 739.2 nautical miles (1,369 km). The modified Bell 8247 engine was qualified for up to 15 restarts. - Undocking, unreeling a 50 feet (15 m) nylon tether between the capsule and the Agena and flying in a "dumbbellDumbbellThe dumbbell, a type of free weight, is a piece of equipment used in weight training. It can be used individually or in pairs .-History:...
" configuration with the Agena below the astronauts (to check the gravitational effect on the formation stability in uncontrolled mode. This technique is now known as Gravity-gradient stabilizationGravity-gradient stabilizationGravity-gradient stabilization is a method of stabilizing artificial satellites or space tethers in a fixed orientation using only the orbited body's mass distribution and the Earth's gravitational field. The main advantage over using active stabilization with propellants, gyroscopes or reaction...
.) - Using a similar tether and a few thruster bursts to rotate the two craft around each other as an early test of artificial gravity.
- After rendezvous with its own ATV, Gemini 10Gemini 10-Backup crew:-Mission parameters:*Mass: *Perigee: *Apogee: *Inclination: 28.87°*Period: 88.79 min-Docking:*Docked: July 19, 1966 - 04:15:00 UTC*Undocked: July 20, 1966 - 19:00:00 UTC-Space walk:...
performed a second rendezvous with the ATV from Gemini 8Gemini 8-Backup crew:-Mission parameters:* Mass: * Perigee: * Apogee: * Inclination: 28.91°* Period: 88.83 min-Objectives:Gemini VIII had two major objectives, of which it achieved one...
.
After the Gemini capsule separated for the last time, the Agena remained in orbit for a short time and was used to verify the command system.
Augmented Target Docking Adapter
A backup vehicle for the ATV, known as the Augmented Target Docking Adapter (ATDA), was constructed by McDonnell from the docking target and the Gemini reentry attitude control thruster assembly for use if the primary ATV failed. The ATDA was designed to allow docking, but lacked the propulsion capability of the Agena rocket. The ATDA was used on Gemini 9AGemini 9A
- Backup crew :- Original primary crew :- Mission parameters :* Mass: * Perigee: * Apogee: * Inclination: 28.91°* Period: 88.78 min- 1st rendezvous :* June 3, 1966 - 17:45 - 18:00 UTC- Spacewalk :* Cernan...
, after the Atlas-Agena launch vehicle failed. However, the Gemini 9 crew could not dock with the ATDA because the nose cone shroud failed to separate properly.
Flight statistics
| Target | Gemini mission | Launched | Reentered | NSSDC ID | Mass | Comments |
|---|---|---|---|---|---|---|
| GATV-5002 | Gemini 6 Gemini 6A -Backup crew:-Mission parameters:* Mass: * Perigee: * Apogee: * Inclination: 28.97°* Period: 88.7 min-Stationkeeping with GT-7:* Start: December 15, 1965 19:33 UTC* End: December 16, 1965 00:52 UTC-Objectives:... |
October 25, 1965 15:00:04 UTC |
October 25, 1965 15:06:20 UTC |
GEM6T | 7190 pounds (3,261.3 kg) | Atlas-Agena exploded during launch. Gemini 6A achieved first rendezvous with Gemini 7 Gemini 7 Gemini 7 was a 1965 manned spaceflight in NASA's Gemini program. It was the 4th manned Gemini flight, the 12th manned American flight and the 20th spaceflight of all time . The crew of Frank F. Borman, II and James A... instead. |
| GATV-5003 | Gemini 8 Gemini 8 -Backup crew:-Mission parameters:* Mass: * Perigee: * Apogee: * Inclination: 28.91°* Period: 88.83 min-Objectives:Gemini VIII had two major objectives, of which it achieved one... |
March 16, 1966 15:00:03 UTC |
September 15, 1967 | 1966-019A | 7000 pounds (3,175.1 kg) | Achieved first docking, but mission soon aborted due to stuck Gemini thruster. ATV later used as secondary target on Gemini 10. |
| GATV-5004 | Gemini 9 | May 17, 1966 15:12:00 UTC |
May 17, 1966 15:19:00 UTC |
GEM9TA | 7170 pounds (3,252.3 kg) | Failed to orbit. |
| ATDA No. 02186 | Gemini 9A Gemini 9A - Backup crew :- Original primary crew :- Mission parameters :* Mass: * Perigee: * Apogee: * Inclination: 28.91°* Period: 88.78 min- 1st rendezvous :* June 3, 1966 - 17:45 - 18:00 UTC- Spacewalk :* Cernan... |
June 1, 1966 15:00:02 UTC |
June 11, 1966 | 1966-046A | 1750 pounds (793.8 kg) | No Agena rocket. Successful rendezvous, but no docking due to shroud separation failure. |
| GATV-5005 | Gemini 10 Gemini 10 -Backup crew:-Mission parameters:*Mass: *Perigee: *Apogee: *Inclination: 28.87°*Period: 88.79 min-Docking:*Docked: July 19, 1966 - 04:15:00 UTC*Undocked: July 20, 1966 - 19:00:00 UTC-Space walk:... |
July 18, 1966 20:39:46 UTC |
December 29, 1966 | 1966-065A | 7000 pounds (3,175.1 kg) | Boosted Gemini 10 to 412 nautical miles (763 km) apogee. |
| GATV-5006 | Gemini 11 Gemini 11 Gemini 11 was the ninth manned spaceflight mission of NASA's Project Gemini, which flew from September 12 to 15, 1966. It was the 17th manned American flight and the 25th spaceflight to that time . Astronauts Charles "Pete" Conrad, Jr. and Richard F. Gordon, Jr... |
September 12, 1966 13:05:01 UTC |
December 30, 1966 | 1966-080A | 7000 pounds (3,175.1 kg) | Boosted Gemini 11 to record 739.2 nautical miles (1,369 km) apogee. First demonstration of artificial gravity created in microgravity. |
| GATV-5001A | Gemini 12 Gemini 12 -Backup crew:-Mission parameters:*Mass: *Perigee: *Apogee: *Inclination: 28.87°*Period: 88.87 min-Docking:*Docked: November 12, 1966 - 01:06:00 UTC*Undocked: November 13, 1966 - 20:18:00 UTC-Space walk:... |
November 11, 1966 19:07:58 UTC |
December 23, 1966 | 1966-103A | 7000 pounds (3,175.1 kg) | No apogee boost due to defective Agena engine. Performed tether experiment. |