List of Apollo missions

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The Apollo program was a United States human spaceflight program carried out from 1961 to 1972 by the National Aeronautics and Space Administration (NASA), which landed the first astronauts on the Moon.[1] The program used the Saturn IB and Saturn V launch vehicles to lift the Command/Service Module (CSM) and Lunar Module (LM) spacecraft into space, and the Little Joe II rocket to test a launch escape system which was expected to carry the astronauts to safety in the event of a Saturn failure.[2] Uncrewed test flights beginning in 1966 demonstrated the safety of the launch vehicles and spacecraft to carry astronauts, and four crewed flights beginning in October 1968 demonstrated the ability of the spacecraft to carry out a lunar landing mission.

The launch of Apollo 11. The rocket is vertical in frame in front of the support structure, with flame shooting out the sides of the launch pad.
Launch of AS-506 space vehicle on July 16, 1969, at pad 39A for mission Apollo 11 to land the first men on the Moon

Apollo achieved the first crewed lunar landing on the Apollo 11 mission, when Neil Armstrong and Buzz Aldrin landed their LM Eagle in the Sea of Tranquility and walked on the lunar surface, while Michael Collins remained in lunar orbit in the CSM Columbia, and all three landed safely on Earth on July 24, 1969.[3] Five subsequent missions landed astronauts on various lunar sites, ending in December 1972 with twelve men having walked on the Moon[4] and 842 pounds (382 kg) of lunar rocks and soil samples returned to Earth, greatly contributing to the understanding of the Moon's composition and geological history.[5]

Two Apollo missions were failures: a 1967 cabin fire killed the entire Apollo 1 crew during a ground test in preparation for what was to be the first crewed flight;[6] and the third landing attempt on Apollo 13 was aborted by an oxygen tank explosion en route to the Moon, which disabled the CSM Odyssey's electrical power and life support systems, and made the propulsion system unsafe to use. The crew circled the Moon and were returned safely to Earth using the LM Aquarius as a "lifeboat" for these functions.[7]

Uncrewed test flights

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From 1961 through 1967, Saturn launch vehicles and Apollo spacecraft components were tested in uncrewed flights.

Saturn I

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The Saturn I launch vehicle was originally planned to carry crewed Command Module flights into low Earth orbit, but its 20,000-pound (9,100 kg) payload capacity limit could not lift even a partially fueled Service Module, which would have required building a lightweight retrorocket module for deorbit. These plans were eventually scrapped, in favor of using the uprated Saturn IB to launch the Command Module with a half-fueled Service Module for crewed Earth orbit tests. This limited Saturn I flights to Saturn launch vehicle development, CSM boilerplate testing, and three micrometeoroid satellite launches in support of Apollo.

Saturn I missions
Mission LV Serial No Launch Remarks Refs
SA-1 Saturn I

SA-1

October 27, 1961,

15:06 GMT Launch Complex 34

Test of Saturn I first stage S-I; dummy upper stages carried water [1][8][9]
SA-2 Saturn I

SA-2

April 25, 1962,

14:00 GMT Launch Complex 34

Dummy upper stages released 22,900 U.S. gallons (86,685 L) of water into upper atmosphere, to investigate effects on radio transmission and changes in local weather conditions [1][8][9]
SA-3 Saturn I

SA-3

November 16, 1962,

17:45 GMT Launch Complex 34

Repeat of SA-2 mission [1][8][9]
SA-4 Saturn I

SA-4

March 28, 1963,

20:11 GMT Launch Complex 34

Test premature shutdown of a single S-I engine [1][8][9]
SA-5 Saturn I

SA-5

January 29, 1964,

16:25 GMT Launch Complex 37B

First flight of live second stage. First orbital flight. [1][8][9]
AS-101 Saturn I

SA-6

May 28, 1964,

17:07 GMT Launch Complex 37B

Tested first boilerplate Apollo command and service module (CSM) for structural integrity [1][9]
AS-102 Saturn I

SA-7

September 18, 1964,

17:22 GMT Launch Complex 37B

Carried first programmable-in-flight computer on the Saturn I vehicle; last launch vehicle development flight [1][9]
AS-103 Saturn I

SA-9

February 16, 1965,

14:37 GMT Launch Complex 37B

Carried first Pegasus micrometeorite satellite (Pegasus A) in addition to boilerplate CSM [1][9]
AS-104 Saturn I

SA-8

May 25, 1965,

07:35 GMT Launch Complex 37B

Carried Pegasus B and boilerplate CSM [1][9]
AS-105 Saturn I

SA-10

July 30, 1965,

13:00 GMT Launch Complex 37B

Carried Pegasus C and boilerplate CSM [1][9]

There was some incongruity in the numbering and naming of the first three uncrewed Apollo-Saturn (AS), or Apollo flights. This is due to AS-204 being renamed to Apollo 1 posthumously. This crewed flight was to have followed the first three uncrewed flights. After the fire which killed the AS-204 crew on the pad during a test and training exercise, uncrewed Apollo flights resumed to test the Saturn V launch vehicle and the Lunar Module; these were designated Apollo 4, 5 and 6. The first crewed Apollo mission was thus Apollo 7. Simple "Apollo" numbers were never assigned to the first three uncrewed flights, although renaming AS-201, AS-202, and AS-203 as Apollo 1-A, Apollo 2 and Apollo 3, had been briefly considered.[6]

Saturn IB

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The Saturn I was converted to the Uprated Saturn I, eventually designated Saturn IB, by replacing the S-IV second stage with the S-IVB, which would also be used as the third stage of the Saturn V with the addition of on-orbit restart capability. This increased the payload capacity to 46,000 pounds (21,000 kg), enough to orbit a Command Module with a half-fueled Service Module, and more than enough to orbit a fully fueled Lunar Module.

Two suborbital tests of the Apollo Block I Command and Service Module, one S-IVB development test, and one Lunar Module test were conducted. Success of the LM test led to cancellation of a planned second uncrewed flight.

Saturn IB missions
Mission LV Serial No Launch Remarks Refs
AS-201 Saturn IB

SA-201

February 26, 1966,

16:12 GMT Launch Complex 34

First test of Saturn IB and Block I Apollo CSM. Suborbital flight landed the CM in the Atlantic Ocean, demonstrating the heat shield. Propellant pressure loss caused premature SM engine shutdown. [1][6][8][9]
AS-203 Saturn IB

SA-203

July 5, 1966,

14:53 GMT Launch Complex 37B

No Apollo spacecraft; instrumentation and video observed on-orbit behavior of S-IVB liquid hydrogen fuel in support of restart capability design for Saturn V. Deemed a success, despite inadvertent destruction of S-IVB during final overpressure tank rupture test. [1][6][8][9]
AS-202 Saturn IB

SA-202

August 25, 1966,

17:15 GMT Launch Complex 34

Suborbital flight to Pacific Ocean splashdown. CM heat shield tested to higher speed; successful SM firings. [1][6][8][9]
Apollo 5 Saturn IB

SA-204

January 22, 1968,

22:48 GMT Launch Complex 37B

First flight of LM successfully fired descent engine and ascent engines; demonstrated "fire-in-the-hole" landing abort test. [1][8][9]

Launch escape system tests

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From August 1963 to January 1966, a number of tests were conducted at the White Sands Missile Range for development of the launch escape system (LES). These included simulated "pad aborts", which might occur while the Apollo-Saturn space vehicle was still on the launch pad, and flights on the Little Joe II rocket to simulate Mode I aborts which might occur while the vehicle was in the air.[1]

 
Pad Abort Test 2 with boilerplate command module
Launch escape system tests
Mission Launch vehicle Launch Remarks Refs
QTV Little Joe II August 28, 1963,

13:05 GMT Launch Complex 36

Little Joe II qualification test [1][9]
Pad Abort Test 1 None November 7, 1963,

16:00 GMT Launch Complex 36

Launch escape system (LES) abort test from launch pad [1][9]
A-001 Little Joe II May 13, 1964,

13:00 GMT Launch Complex 36

LES transonic test, success except for parachute failure [1][9]
A-002 Little Joe II December 8, 1964,

15:00 GMT Launch Complex 36

LES maximum altitude, Max-Q abort test [1][9]
A-003 Little Joe II May 19, 1965,

13:01 GMT Launch Complex 36

LES canard maximum altitude abort test [1][9]
Pad Abort Test 2 None June 29, 1965,

13:00 GMT Launch Complex 36

LES pad abort test of near Block-I CM [1][9]
A-004 Little Joe II January 20, 1966,

15:17 GMT Launch Complex 36

LES test of maximum weight, tumbling Block-I CM [1][9]

Saturn V

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Prior to George Mueller's tenure as NASA's Associate Administrator for Manned Space Flight starting in 1963, it was assumed that 20 Saturn Vs, with at least 10 unpiloted test flights, would be required to achieve a crewed Moon landing, using the conservative one-stage-at-a-time testing philosophy used for the Saturn I. But Mueller introduced the "all-up" testing philosophy of using three live stages plus the Apollo spacecraft on every test flight. This achieved development of the Saturn V with far fewer uncrewed tests, and facilitated achieving the Moon landing by the 1969 goal. The size of the Saturn V production lot was reduced from 20 to 15 units.[10]

Three uncrewed test flights were planned to human-rate the super heavy-lift Saturn V which would take crewed Apollo flights to the Moon. Success of the first flight and qualified success of the second led to the decision to cancel the third uncrewed test.

Saturn V missions
Mission LV Serial No Launch Remarks Refs
Apollo 4 Saturn V

SA-501

November 9, 1967,

12:00 GMT Launch Complex 39A

First flight of Saturn V rocket; successfully demonstrated S-IVB third stage restart and tested CM heat shield at lunar re-entry speeds. [1][8][9]
Apollo 6 Saturn V

SA-502

April 4, 1968,

16:12 GMT Launch Complex 39A

Second flight of Saturn V; severe "pogo" vibrations caused two second-stage engines to shut down prematurely, and third stage restart to fail. SM engine used to achieve high-speed re-entry, though less than Apollo 4. NASA identified vibration fixes and declared Saturn V man-rated. [1][8][9]

Alphabetical mission types

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The Apollo program required sequential testing of several major mission elements in the runup to a crewed lunar landing. An alphabetical list of major mission types was proposed by Owen Maynard in September 1967.[11][12] Two "A-type" missions performed uncrewed tests of the CSM and the Saturn V, and one B-type mission performed an uncrewed test of the LM. The C-type mission, the first crewed flight of the CSM in Earth orbit, was performed by Apollo 7.

The list was revised upon George Low's proposal to commit a mission to lunar orbit ahead of schedule, an idea influenced by the status of the CSM as a proven craft and production delays of the LM.[13] Apollo 8 was reclassified from its original assignment as a D-type mission, a test of the complete CSM/LM spacecraft in Earth orbit, to a "C-prime" mission which would fly humans to the Moon. Once complete, it obviated the need for the E-type objective of a medium Earth orbital test. The D-type mission was instead performed by Apollo 9; the F-type mission, Apollo 10, flew the CSM/LM spacecraft to the Moon for final testing, without landing. The G-type mission, Apollo 11, performed the first lunar landing, the central goal of the program.

The initial A–G[11][14] list was expanded to include later mission types:[1]: 466  H-type missions—Apollo 12, 13 (planned) and 14—would perform precision landings, and J-type missions—Apollo 15, 16 and 17—would perform thorough scientific investigation. The I-type objective, which called for extended lunar orbital surveillance of the Moon,[15] was incorporated into the J-type missions.[1]: 466 

Alphabetical mission types of the Apollo Program
Missions Mission type Description
A Unmanned flights of launch vehicles and the CSM, to demonstrate the adequacy of their design and to certify safety for men.[14][a]
Apollo 5 B Unmanned flight of the LM, to demonstrate the adequacy of its design and to certify its safety for men.[14]
Apollo 7 C Manned flight to demonstrate performance and operability of the CSM.[14]
Apollo 8 C′ Command and service module manned flight demonstration in lunar orbit.[1]: 466 
Apollo 9 D Manned flight of the complete lunar landing mission vehicle in low Earth orbit to demonstrate operability of all the equipment and (insofar as could be done in Earth orbit) to perform the maneuvers involved in the ultimate mission.[14]
E Manned flight of the complete lunar landing mission vehicle in Earth orbit to great distances from Earth.[14]
Apollo 10 F A complete mission except for the final descent to and landing on the lunar surface.[14]
Apollo 11 G The initial lunar landing mission.[14]
H Precision manned lunar landing demonstration and systematic lunar exploration.[1]: 466 
I Reserved for lunar survey missions. (Not used)[15]
J Extensive scientific investigation of Moon on lunar surface and from lunar orbit.[1]: 466 

Crewed missions

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The Block I CSM spacecraft did not have capability to fly with the LM, and the three crew positions were designated Command Pilot, Senior Pilot, and Pilot, based on U.S. Air Force pilot ratings. The Block II spacecraft was designed to fly with the Lunar Module, so the corresponding crew positions were designated Commander, Command Module Pilot, and Lunar Module Pilot regardless of whether a Lunar Module was present or not on any mission.[16]

Seven of the missions involved extravehicular activity (EVA), spacewalks or moonwalks outside of the spacecraft. These were of three types: testing the lunar EVA suit in Earth orbit (Apollo 9), exploring the lunar surface, and retrieving film canisters from the Scientific Instrument Module stored in the Service Module.[17]

Canceled missions

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Several planned missions of the Apollo program were canceled for a variety of reasons, including changes in technical direction, the Apollo 1 fire, hardware delays, and budget limitations.

  • Before the Apollo 1 fire, two crewed Block I spacecraft missions were planned, but then it was decided that the second one would give no more information about the spacecraft performance not obtained from the first, and could not carry out extra activities such as EVA, and was canceled.
  • The Saturn V's all-up testing strategy and relatively good success rate accomplished the first Moon landing on the sixth flight, leaving ten available for Moon landings through Apollo 20,[44] but waning public interest in the program led to decreased Congressional funding, forcing NASA to economize. First, Apollo 20 was cut to make a Saturn V available to launch the Skylab space station whole instead of building it on-orbit using multiple Saturn IB launches.[45] Eight months later, Apollo 18 and 19 were also cut to further economize, and because of fears of increased chance of failure with a large number of lunar flights.[46][47]
Canceled missions
As planned As flown
Mission Type Date Landing site CDR CMP LMP Mission Launch date Landing site CDR CMP LMP
Apollo 12[c] H November 1969 Ocean of Storms Pete Conrad Richard F. Gordon Jr. Alan Bean Apollo 12 November 14, 1969 Ocean of Storms Pete Conrad Richard F. Gordon Jr. Alan Bean
Apollo 13 H March 1970 Fra Mauro highlands Alan Shepard Stuart Roosa Edgar Mitchell Apollo 13 April 11, 1970 Failed Jim Lovell Jack Swigert Fred Haise
Apollo 14 H July 1970 Censorinus crater Jim Lovell Ken Mattingly Fred Haise Apollo 14 January 31, 1971 Fra Mauro highlands Alan Shepard Stuart Roosa Edgar Mitchell
Apollo 15 H November 1970 Littrow crater David Scott Alfred Worden James Irwin Apollo 15 July 26, 1971 Hadley Rille David Scott Alfred Worden James Irwin
Apollo 16 J April 1971 Tycho crater John Young Jack Swigert Charles Duke Apollo 16 April 16, 1972 Descartes Highlands John Young Ken Mattingly Charles Duke
Apollo 17 J September 1971 Marius Hills Gene Cernan Ronald Evans Joe Engle Apollo 17 December 7, 1972 Taurus-Littrow Gene Cernan Ronald Evans Harrison Schmitt
Apollo 18 J February 1972 Schroter's Valley Richard F. Gordon Jr. Vance Brand Harrison Schmitt CANCELED September 1970
Apollo 19 J July 1972 Hyginus Rille Fred Haise William Pogue Gerald Carr CANCELED September 1970
Apollo 20 J December 1972 Copernicus crater Stuart Roosa Don L. Lind Jack Lousma CANCELED January 4, 1970

See also

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There were two NASA post-Apollo crewed spaceflight programs that used Apollo hardware:[48]

Notes

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  1. ^ Although the A-type designation was used in official documents to refer only to Apollo 4 and Apollo 6,[1]: 466  specifically their uncrewed orbital flights of the CSM and use of the Saturn V rocket, Samuel C. Phillips also used the A-type designation to refer to AS-201, AS-203 and AS-202: "A. Unmanned flights of launch vehicles and the CSM, to demonstrate the adequacy of their design and to certify safety for men. Five of these flights were flown between February 1966 and April 1968; Apollo 6 was the last."[14]
  2. ^ Serial number displayed in parentheses
  3. ^ If Apollo 11 was unable to land on the moon, Apollo 12 would have been the US's next attempt. With the successful landing, Apollo 12 was converted to a geological mission.

References

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Bibliography

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