Canceled Apollo missions
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Canceled Apollo missions
Due to budget constraints there were many canceled Apollo missions during the Apollo program. Along with Apollos 18, 19 and 20, which received some level of planning, there were a variety of later planned flights. Some of these were incorporated into the Apollo Applications Program, of which the only result was the Skylab space station.
Mission typesIn September 1967, the Manned Spacecraft Center in Houston, Texas, proposed a series of missions that would lead up to a manned lunar landing. Seven mission types were outlined, each testing a specific set of components and tasks; each previous step needed to be completed successfully before the next mission type could be undertaken. These were:
Later added to this were H missions, which were short duration stays on the Moon with two LEVAs ("moonwalks"). These were followed by the J missions, which were longer three day stays, with three LEVAs and the use of the lunar rover. Apollo 18 to 20 would have been J missions. In addition, a further group of flights?the I missions?were planned for. Lunar Orbital Survey Missions were conceived that would have seen a long duration orbital mission of the Moon using a Service Module bay loaded with scientific equipment. When it became obvious that later flights were being canceled, such mission plans were brought into the J missions that were actually flown. Early Apollo missions
The prime crew for the second planned Apollo manned flight prepares for mission simulator tests at the North American Aviation plant. Left to right: Donn F. Eisele, Senior Pilot, Walter M. Schirra, Command Pilot, and Walter Cunningham, Pilot. (September 1966). In 1962 it was planned to fly four manned Saturn I flights in 1965. These flights would be designated SA-11 through SA-14 and would be orbital flights. However by late 1963 a change in NASA testing to "all-up" led to the missions being canceled. Other missions received much more planning. It was originally planned that Apollo 1 would be followed by another Earth orbital flight of the Block I Command/Service Module (the Block I version was only designed for Earth orbit and not lunar flights). However it was decided that the flight was unnecessary and officially canceled on December 22, 1966. The crew of Walter Cunningham, Donn Eisele and Wally Schirra became the backup crew for Apollo 1 and eventually the crew for Apollo 7. Also planned was the original D mission. Instead of using a Saturn V to launch the CSM and LM in one launch, this mission would have used two Saturn IBs to launch the components separately. It would have used the first block II CSM, CSM-101, and Lunar Module LM-2. CSM-101 was used by Apollo 7 and LM-2 went unused (Apollo 9 used LM-3) and currently is on display at the Smithsonian National Air and Space Museum. The D mission crew would end up flying on Apollo 9. Of all the components of the Apollo system, the LM, which would eventually be used to land on the Moon, had the most issues. It was behind schedule and when the first model was shipped to Cape Canaveral in June 1968, over 101 separate defects were discovered. Grumman Aircraft Engineering Corporation, which was the lead contractor for the LM predicted that the first mannable LM, to be used for the D mission, would not be ready until at least February 1969, delaying the entire sequence. George Low, the Manager of the Apollo Spacecraft Program Office, proposed a solution in August. Since the CSM would be ready three months before the Lunar Module, they could fly a CSM-only mission in December 1968. But instead of just repeating the flight of Apollo 7, the C mission that would fly the CSM in Earth orbit, they could send the CSM all the way to the Moon and maybe even enter into orbit. This mission was dubbed the "C-Prime" mission. This new mission would allow NASA to test procedures that would be used on the manned lunar landings that would otherwise have to wait until Apollo 10, the F mission. There were also concerns from the CIA that the Soviets were planning their own circumlunar flight for December to upstage the Americans once again (see Zond program). This change of plans for Apollo 8 meant the cancellation of the E mission. The switch of missions was also decisive in who would be the first man to walk on the moon. Pete Conrad was back up Commander for the D mission that became Apollo 9 and by the process of crew rotation would have been in line for prime crew Commander of Apollo 11. Apollos 18?20Originally, NASA produced fifteen flight-worthy Saturn Vs. This was enough to provide for two unmanned tests and thirteen manned missions. The thirteen manned missions included the ten missions Apollo 8 through Apollo 17 that were actually flown, and the three canceled missions Apollo 18 through Apollo 20. CancellationThe first mission to be canceled was Apollo 20. On January 4, 1970 NASA announced it was canceling the Apollo 20 as its Saturn V rocket was now needed for the Skylab space station and budget restrictions had limited the Saturn V production to the original 15 flight models. [1]. NASA Deputy Administrator George M. Low announced at that time that the final three moon landings were rescheduled for 1973 and 1974, after three planned Skylab missions. [2]. Originally scheduled for July 1972, under a timetable where lunar missions would be launched every four months, Apollo 20 had been scheduled to land in the Copernicus crater. [3]. Then, on September 2, 1970, NASA announced it was canceling what were to be the Apollo 15 and Apollo 19 missions. At the time, 35 of NASA's 49 active astronauts were waiting for a chance for a mission [4] Apollo 15 was originally meant to be an H mission ? like Apollo 12, 13 and 14. These cancellations meant that Apollo 15 became a J mission ? three day stay on the moon with the lunar rover and that Apollo 19 would no longer be launched. CrewsDeke Slayton was the Director of Flight Crew Operations and effectively chose the crews for the flights. During the early Apollo missions he had used a rotation system of assigning a crew as backup and then three missions later they would be the prime crew. However, by the later Apollo flights, this system was used less frequently as astronauts left the program, Slayton wanted to give rookies a chance, and astronauts didn't want to take dead-end backup positions. In the case of Apollo 18 the crew was probably the Apollo 15 backup crew:
When Apollo 18 was effectively canceled, Schmitt was moved up to Apollo 17, replacing Joe Engle, under pressure from the scientific community. Schmitt, a geologist, became the only professional scientist and the twelfth man to walk on the Moon. Slayton's intention for the Apollo 19 crew was the original (prior to cancellation) Apollo 16 backup crew[5]:
For Apollo 20 there is even more uncertainty. Based on normal crew rotation, the crew would have been:
However, Conrad had already walked on the moon on Apollo 12 and there was an unwritten policy that astronauts only got one landing/moonwalk mission. Given this, Conrad and Weitz were transferred to the Skylab program. Thus it is commonly thought that the Apollo 20 crew would have been:
The choice of Roosa as commander for the flight is based on the established rotation pattern (with minor exceptions) of promoting astronauts previously flown as command module pilots to the command of a landing mission as they would have been the only crew member on their prior flight to have not walked on the moon. As command module pilot of Apollo 14 it would be reasonable to assume Roosa would have rotated (as per established rotation patterns) to the backup commander position on Apollo 17 and thus been in line to be named prime crew commander had Apollo 20 not been canceled. Surplus hardware
LM-2 on display at the National Air and Space Museum Two complete Saturn Vs went unused after the Apollo program, SA-514 and -515, as well as the third stage of the SA-513. SA-513 was the original launch vehicle destined for the Apollo 18 mission; it was used to launch Skylab (its third stage built from a converted S-IVB #212).
Likewise the flights Apollo Command/Service Modules (CSM) and Apollo Lunar Modules (LM) went either unused or were used for other missions:
Landing sitesBeing effectively canceled at least two years before they would have launched, little detailed planning had happened for the missions. A variety of landing sites were given for each flight. According to "NASA OMSF, Manned Space Flight Weekly Report" from July 28, 1969, Apollo 18 would have landed at Schroter's Valley in February 1972, Apollo 19 in the Hyginus rille region in July 1972, and Apollo 20 in Copernicus in December 1972. In the NASA report "Scientific Rationale Summaries for Apollo Candidate Lunar Exploration Landing Sites" from March 11, 1970, Apollo 18 is targeted for Copernicus, and Apollo 19 is assigned Hadley rille (the eventual landing site of Apollo 15). The Apollo 20 mission had two months before been cancelled, but the report still suggested its target, Hyginus rille, possibly as an alternative Apollo 19 landing site. Another source[6] lists the prospective landing sites as Gassendi craters (Apollo 18, July 1973), Copernicus (Apollo 19, December 1973), and Marius Hills or Tycho (Apollo 20, July 1974). Following the failure of Apollo 13 in April 1970 the landing sites for the remaining moon landings were changed. On September 2, 1970, two missions were cancelled: Apollo 15, an early mission that probably would have gone to Censorinus, and Apollo 19, an advanced mission that would possibly have had Copernicus as its destination. The remaining missions were renumbered 14 through 17. Apollo 21A number of sources refer to an Apollo 21 lunar-landing mission, cancelled around 1969.[7] While this seems unlikely, as there would not have been a Saturn V to launch the flight, the discrepancy is likely due to Apollo 8. Apollo 8 was originally slated to be a D mission, flying the LM and CSM in Earth orbit. However, the LM was delayed by engineering problems, and the mission would not be able to fly as planned. As such, NASA changed the mission plan to be a "C-prime" mission ? it would only consist of the manned CSM, but it would go all the way to the Moon. This would, of course, require the use of a Saturn V, leaving twelve more for later missions. Initially, however, the plan had been for the D mission to consist of two separate flights, with one Saturn IB carrying the CSM and, a few days later, another launching with the LM. Had this been carried out, there would have been thirteen Saturn Vs left after Apollo 8 - in other words, enough to go to a hypothetical Apollo 21. It is likely that references to Apollo 21 originate in this short period between the flight of Apollo 7, and the announcement of the change of mission of Apollo 8. The knowledge that the C mission was numbered 7 allowed the calculation that there would be a D mission, and then thirteen missions requiring Saturn Vs, to a final Apollo 21. After Apollo 8, however, it became clear that all future Apollo missions would be on Saturn Vs ? and the boosters would end at number 20. At the time, no specific plans for the late Apollo missions, besides rough dates, existed. Using the internal NASA numbering conventions of the time, the "Apollo 21" discussed in 1968 would have been SA-515. This was the numbering used for the canceled Apollo 20 mission; in other words, Apollo 21 was simply an early name for the mission that later became planned as Apollo 20. SkylabDuring Skylab 3, a malfunction on the Apollo CSM docked to the station caused fears that the crew would not be able to return safely. The 1969 film Marooned depicted a fictional space disaster involving an Apollo CSM. After the film's release, in November 1970, North American Rockwell engineers drafted a plan to modify an existing Apollo CSM into a rescue vehicle configuration. A modified Apollo CSM was prepared, with two additional crew seats placed on the floor below the capsule's three couches. Two astronauts, Vance Brand and Don Lind, would have flown the Apollo spacecraft to Skylab's auxiliary docking port to retrieve the crew. However, the problem was fixed without requiring a rescue flight, and the mission was stood down. The CSM was later used as a backup for the Apollo-Soyuz Test Project. As of 2005 it is on display at the Kennedy Space Center's Apollo-Saturn V Center (the only intact CSM in existence). NASA engineers supporting the Constellation Program examined this CSM during their design work. Along with the Skylab Rescue mission, there were also plans for a short 20-day Skylab 5 flight that would use this backup CSM. The crew, consisting of Brand, Lind, and William B. Lenoir (as the Command Module Pilot), would have performed some scientific research and boosted the station into a higher orbit for use by the Space Shuttle. Another plan would have been to use the backup Skylab (known as "Skylab B") that had been constructed and launch it using one of the surplus Saturn V rockets left over from the cancellation of later lunar landing missions. It would have been served by Apollo spacecraft and perhaps been used for the Apollo-Soyuz Test Project. In fictionApollo 18
Apollo 19
Apollo 20
Apollo 21
Notes
References
External links
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