As with most programs in the space business, Project Mercury was given daring objectives to accomplish and the proposed methods of completing these objectives were expected to take up many resources and require numerous missions. An example of how the requirements during the planning stages for a program can differ greatly to the way the program actually turns out, is the number of Saturn V flights originally required to complete the Apollo Program. At one time NASA thought that up to fifteen Saturn V launches would be required before the lunar landing could be attempted, in the end NASA only flew thirteen Saturn V's all together during Apollo and Skylab.
In a similar fashion, NASA at one time envisaged that all the astronauts in the first group would complete a sub-orbital mission aboard a Redstone Rocket before moving onto orbital missions which would take place every sixty days. After August 1961 it was decided that no more manned sub-orbital flights would take place, probably due to the Russians success at orbital flights, and Mercury-Redstone 5 and Mercury-Redstone 6 were cancelled. Therefore Glenn and Slayton lost their Mercury-Redstone sub-orbital flights and moved up to Mercury-Atlas 6, Glenn and Mercury-Atlas 7, Slayton, both orbital missions.
Following this pattern of using many flights to accomplish the Mercury Program, NASA planned on using four missions of one day duration to test how man and machine would perform in orbit. This was included in the schedule up until April 1962 when it was decided that only Mercury-Atlas 9 and Mercury-Atlas 10 would conduct missions over one day. As a result of this Grissom lost Mercury-Atlas 11 and Schirra lost Mercury-Atlas 12.
On the 13th August 1961 spacecraft No.15 arrived at the Florida space centre but was later sent back to the McDonnell plant to be modified for a mission of over one day. Following technical changes it was once again delivered to the Cape on 16th November 1962 and re-designated spacecraft 15A to be used as a back-up for Mercury-Atlas 9 and then used for Mercury-Atlas 10.
Mercury-Atlas 10 would fly if all the required data from Mercury-Atlas 9 was not collected and possibly on a six day mission. In light of this extended mission the spacecraft was re-designated spacecraft 15B and from January 1963 more changes were made to enable it to last in space for its long duration mission.
On 17th January, Dr Robert C. Seamans told a Congressional committee that flights after Mercury-Atlas 9 would be possible with spaceraft that were already available should any data still be required to accomplish all the goals of the project. At the beginning of June of 1963 it was put to James E. Webb that due to the fact that the spacecraft and rocket were ready to fly, one of the major goals of the upcoming Gemini Program could be accomplished far cheaper by having a man stay in space for up to ten days.
As with all previous Mercury spacecraft, Alan Shepard had his chosen name for the mission painted onto the side in anticipation of flying his second Mercury Mission. Since the end of 1962 his spacecraft had been at the Cape and in January 1963 modifications had been started for a long duration mission, in the same month further missions after Mercury-Atlas 9 were still being considered so it was not unreasonable for Shepard to name and paint his spacecraft as had all the previous astronauts before their missions.
Spacecraft 15B and Alan Shepard were ready to fly Mercury-Atlas 10 but on 12th June, James E. Webb testified before the Senate Space Committee that Mercury-Atlas 9 was to be the final mission of the project. With the Gemini Program now the major focus of space activity it was decided that the risks involved in pushing the Mercury spacecraft way past their intended capabilities wasn't worth it and that with six successful missions accomplishing the goal of putting a man into space, keeping him alive and bringing him safely back down to Earth, no further missions were required. |
