| Apollo drogue and probe assemblies. The docking ring is part of the Apollo Command Module. | |
| Module statistics | |
|---|---|
| Docked | 19 times |
| Diameter | 32 inches (81 cm) |
The docking mechanism of the Apollo was a "probe and drogue" system designed to allow the Apollo Command/Service Module (CSM) to dock with the Apollo Lunar Module. The same system was later used for the Skylab 2, Skylab 3 and Skylab 4 CSMs to dock with the Skylab space station, and the Apollo–Soyuz Test Project CSM to dock with a Docking Module adapter which allowed docking with the Soyuz 19 spacecraft. There were 12 hard latches. [1] [2] [3]
The Apollo system differed from the Gemini Docking Mechanism in that after locking, the probe and drogue mechanism could be manually removed to allow access between the two docked craft. Ideas from this system were instrumental in creating later systems, like those used in the Space Shuttle, the International Space Station, and others. [4]
The Apollo docking system was used successfully in thirteen missions in Earth and lunar orbits between 1969 and 1975. The only serious problems were experienced on Apollo 14 and Skylab 2, when the probe systems failed to capture the drogue receptacles during repeated docking attempts. Successful docking was eventually accomplished in both missions. [5]
The Apollo program, also known as Project Apollo, was the United States human spaceflight program carried out by the National Aeronautics and Space Administration (NASA), which succeeded in preparing and landing the first men on the Moon from 1968 to 1972. It was first conceived in 1960 during President Dwight D. Eisenhower's administration as a three-person spacecraft to follow the one-person Project Mercury, which put the first Americans in space. Apollo was later dedicated to President John F. Kennedy's national goal for the 1960s of "landing a man on the Moon and returning him safely to the Earth" in an address to Congress on May 25, 1961. It was the third US human spaceflight program to fly, preceded by the two-person Project Gemini conceived in 1961 to extend spaceflight capability in support of Apollo.
Apollo 7 was the first crewed flight in NASA's Apollo program, and saw the resumption of human spaceflight by the agency after the fire that had killed the three Apollo 1 astronauts during a launch rehearsal test on January 27, 1967. The Apollo 7 crew was commanded by Walter M. Schirra, with command module pilot Donn F. Eisele and Lunar Module pilot R. Walter Cunningham.
Apollo 9 was the third human spaceflight in NASA's Apollo program. Flown in low Earth orbit, it was the second crewed Apollo mission that the United States launched via a Saturn V rocket, and was the first flight of the full Apollo spacecraft: the command and service module (CSM) with the Lunar Module (LM). The mission was flown to qualify the LM for lunar orbit operations in preparation for the first Moon landing by demonstrating its descent and ascent propulsion systems, showing that its crew could fly it independently, then rendezvous and dock with the CSM again, as would be required for the first crewed lunar landing. Other objectives of the flight included firing the LM descent engine to propel the spacecraft stack as a backup mode, and use of the portable life support system backpack outside the LM cabin.
The Apollo Lunar Module, originally designated the Lunar Excursion Module (LEM), was the lunar lander spacecraft that was flown between lunar orbit and the Moon's surface during the United States' Apollo program. It was the first crewed spacecraft to operate exclusively in the airless vacuum of space, and remains the only crewed vehicle to land anywhere beyond Earth.
Apollo–Soyuz was the first crewed international space mission, carried out jointly by the United States and the Soviet Union in July 1975. Millions of people around the world watched on television as an American Apollo spacecraft docked with a Soviet Soyuz capsule. The project, and its handshake in space, was a symbol of détente between the two superpowers during the Cold War.
The Apollo spacecraft was composed of three parts designed to accomplish the American Apollo program's goal of landing astronauts on the Moon by the end of the 1960s and returning them safely to Earth. The expendable (single-use) spacecraft consisted of a combined command and service module (CSM) and an Apollo Lunar Module (LM). Two additional components complemented the spacecraft stack for space vehicle assembly: a spacecraft–LM adapter (SLA) designed to shield the LM from the aerodynamic stress of launch and to connect the CSM to the Saturn launch vehicle and a launch escape system (LES) to carry the crew in the command module safely away from the launch vehicle in the event of a launch emergency.
The Saturn IB(also known as the uprated Saturn I) was an American launch vehicle commissioned by the National Aeronautics and Space Administration (NASA) for the Apollo program. It uprated the Saturn I by replacing the S-IV second stage, with the S-IVB. The S-IB first stage also increased the S-I baseline's thrust from 1,500,000 pounds-force (6,700,000 N) to 1,600,000 pounds-force (7,100,000 N) and propellant load by 3.1%. This increased the Saturn I's low Earth orbit payload capability from 20,000 pounds (9,100 kg) to 46,000 pounds (21,000 kg), enough for early flight tests of a half-fueled Apollo command and service module (CSM) or a fully fueled Apollo Lunar Module (LM), before the larger Saturn V needed for lunar flight was ready.
The Skylab Rescue Mission was an unflown rescue mission, planned as a contingency in the event of astronauts being stranded aboard the American Skylab space station. If flown, it would have used a modified Apollo Command Module that could be launched with a crew of two and return a crew of five.
The Apollo command and service module (CSM) was one of two principal components of the United States Apollo spacecraft, used for the Apollo program, which landed astronauts on the Moon between 1969 and 1972. The CSM functioned as a mother ship, which carried a crew of three astronauts and the second Apollo spacecraft, the Apollo Lunar Module, to lunar orbit, and brought the astronauts back to Earth. It consisted of two parts: the conical command module, a cabin that housed the crew and carried equipment needed for atmospheric reentry and splashdown; and the cylindrical service module which provided propulsion, electrical power and storage for various consumables required during a mission. An umbilical connection transferred power and consumables between the two modules. Just before reentry of the command module on the return home, the umbilical connection was severed and the service module was cast off and allowed to burn up in the atmosphere.
A space rendezvous is a set of orbital maneuvers 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 and position vectors of the two spacecraft, allowing them to remain at a constant distance through orbital station-keeping. Rendezvous may or may not be followed by docking or berthing, procedures which bring the spacecraft into physical contact and create a link between them.
A space capsule is a spacecraft designed to transport cargo, scientific experiments, and/or astronauts to and from space. Capsules are distinguished from other spacecraft by the ability to survive reentry and return a payload to the Earth's surface from orbit or sub-orbit, and are distinguished from other types of recoverable spacecraft by their blunt shape, not having wings and often containing little fuel other than what is necessary for a safe return. Capsule-based crewed spacecraft such as Soyuz or Orion are often supported by a service or adapter module, and sometimes augmented with an extra module for extended space operations. Capsules make up the majority of crewed spacecraft designs, although one crewed spaceplane, the Space Shuttle, has flown in orbit.
The Apollo Applications Program (AAP) was created as early as 1966 by NASA headquarters to develop science-based human spaceflight missions using hardware developed for the Apollo program. AAP was the ultimate development of a number of official and unofficial Apollo follow-on projects studied at various NASA labs. However, the AAP's ambitious initial plans became an early casualty when the Johnson Administration declined to support it adequately, partly in order to implement its Great Society set of domestic programs while remaining within a $100 billion budget. Thus, Fiscal Year 1967 ultimately allocated $80 million to the AAP, compared to NASA's preliminary estimates of $450 million necessary to fund a full-scale AAP program for that year, with over $1 billion being required for FY 1968. The AAP eventually led to Skylab, which absorbed much of what had been developed under Apollo Applications.
Several planned missions of the Apollo crewed Moon landing program of the 1960s and 1970s were canceled, for reasons which included changes in technical direction, the Apollo 1 fire, hardware delays, and budget limitations. After the landing by Apollo 12, Apollo 20, which would have been the final crewed mission to the Moon, was canceled to allow Skylab to launch as a "dry workshop". The next two missions, Apollos 18 and 19, were later canceled after the Apollo 13 incident and further budget cuts. Two Skylab missions also ended up being canceled. Two complete Saturn V rockets remained unused and were put on display in the United States.
The terms Androgynous Peripheral Attach System (APAS), Androgynous Peripheral Assembly System (APAS) and Androgynous Peripheral Docking System (APDS) are used interchangeably to describe a Russian family of spacecraft docking mechanisms, and are also sometimes used as generic names for any docking system in that family. A system similar to APAS-89/95 is used by the Chinese Shenzhou spacecraft.
Soyuz 7K-OK was the first generation of Soyuz spacecraft and was flown between 1967 and 1971. The 7K-OK was used for the first ferry flights to the Salyut space station program, beginning a long history of space station service that continues with the International Space Station (ISS).
Skylab B was a proposed second US space station similar to Skylab that was planned to be launched by NASA for different purposes, mostly involving the Apollo–Soyuz Test Project, but was canceled due to lack of funding. Two Skylab modules were built in 1970 by McDonnell Douglas for the Skylab program, originally the Apollo Applications Program. The first was launched in 1973 and the other put in storage, while NASA considered how to use the remaining assets from Apollo.
Transposition, docking, and extraction was a maneuver performed during Apollo lunar landing missions from 1969 to 1972, to withdraw the Apollo Lunar Module (LM) from its adapter housing which secured it to the Saturn V launch vehicle upper stage and protected it from the aerodynamic stresses of launch. The maneuver involved the command module pilot separating the Apollo Command and Service Module (CSM) from the adapter, turning the CSM around, and docking its nose to the Lunar Module, then pulling the combined spacecraft away from the upper stage. It was performed shortly after the trans-lunar injection maneuver that placed the Apollo spacecraft on a three-day trajectory to the Moon. The docking created a continuous, pressurized tunnel which permitted the astronauts to transfer internally between the CSM and the LM.
Docking and berthing of spacecraft is the joining of two space vehicles. This connection can be temporary, or partially permanent such as for space station modules.
Soyuz Kontakt(Soyuz Contact) was the docking hardware of the Soviet crewed lunar spacecraft program. The Soviet lunar human program was canceled in 1974 after many failures. Four failures of the N-1 Rocket super heavy-lift launch vehicle and the success of the U.S. Apollo program ended the Soviet crewed moon program.