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Grissom

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By the end of 1963. (Cancelled flight). Crew: Grissom. Backup Crew: Schirra. Program: Mercury. On July 27, 1961 NASA met with McDonnell engineers to discuss modification of the Mercury spacecraft for Project MODM (Manned One-Day Mission). On October 25, 1961 NASA authorized McDonnell to proceed with the modification of four capsules and associated testing to support four manned MODM flights beginning in late 1962 and finishing by the end of 1963. From then until April 1962 NASA’s Mercury program plan included four one-day flights in 1963: MA-10 through MA-13. But by October 1962 the decision was taken to cancel the last short-duration flight and move directly to the one-day flights. Therefore Carpenter’s MA-9 flight switched capsules from the short duration SC19 to the long-duration SC20. By this time the decision had been quietly taken to limit the long-duration flights to only MA-9 and MA-10 (SC15B). There were several good reasons for this. The Mercury program was behind schedule and it would be difficult to fly more than two long-duration flights before the mandated completion of the program at the end of 1963. The flight roster of astronauts had been reduced to four, and of these only Grissom would not have made an orbital flight.

If SC12B had flown on a long-duration flight it would have been crewed by Grissom. Given the plans to follow SC15B for three days, it probably also would have undertaken a three to six day flight. Grissom was however already deeply involved with the follow-on project Gemini. It is likely that, as a test pilot, he considered commanding the first manned Gemini flight a far superior assignment to spending several days in the cramped, trouble-prone Mercury design that had already tried to kill him once. Cooper would have been the only available alternate pilot.

• - 1961 July 27-28 - Advanced Mercury concepts  Spacecraft: Mercury Mark I, Gemini.

  After the 2-man space concept (later designated Project Gemini) was introduced in May 1961, a briefing between McDonnell and NASA personnel was held on the matter. As a result of this meeting, space flight design effort was concentrated on the 18-orbit 1-man Mercury and on a 2-man spacecraft capable of advanced missions.

• 1961 Oct 25 - NASA Headquarters officially approved the Mercury extended range or 1-day mission program.  Spacecraft: Mercury.

  Four Mercury spacecraft were to be modified to the Mercury One Day Mission (MODM) configuration.

• - 1962 January - Aerial drop tests planned for the Mercury 1-day mission.  Spacecraft: Mercury.

  Twenty spacecraft aerial drop tests were planned for the Mercury extended range or 1-day mission. One of the prime objectives was to determine if the 63-foot ringsail main recovery parachute met all Mercury mission weight requirements. Tests were scheduled to be conducted at El Centro, California, and all tests would be land drops. This test program was designated Project Reef.

• - 1962 January - Three potential recovery areas were recommended for the Mercury extended range or 1-day mission. 

  These were: Grand Turk, Midway Island, and the Japanese-Philippine Island area.

• - 1962 March - PERT system for Mercury. 

  The PERT (Program Evaluation and Review Technique) reporting system became operational on an experimental basis for Mercury. The first PERT report on the Mercury 1-day mission schedule and cost analysis was issued by the Manned Spacecraft Center on April 26, 1962.

• - 1962 April - Development of an advanced Mercury suit started.  Spacecraft: Mercury Space Suit.

  Development of an advanced state-of-the-art pressure suit and helmet was started. This action was taken in preparation for the Mercury extended range or 1-day mission program. The objectives were aimed at improvements in unpressurized suit comfort, suit ventilation, pressure suit mobility, electrically heated helmet visor with additional light attenuation features, and the fabrication of a mechanical visor seal mechanism.

• 1962 Jun 26 - Mercury Project Reef  Spacecraft: Mercury.

  Project Reef, an airdrop program to evaluate the Mercury 63-foot ringsail main parachute's capability to support the higher spacecraft weight for the extended range or 1-day mission was completed. Tests indicated that the parachute qualified to support the mission.

• 1962 Jun 29 - Changes to fuel tank for the Mercury 1-day mission.  Spacecraft: Mercury.

  Engineering was completed for the spacecraft reaction control system reserve fuel tank and related hardware in support of the Mercury extended range or 1-day mission.

• - 1962 August - The first edition of the map for the Mercury 1-day mission was published. 

• 1962 Aug 8 - Mercury Project Orbit  Spacecraft: Mercury.

  Spacecraft 9 (redesignated 9A) was phased into the Project Orbit program in preparation for the Mercury extended range or 1-day mission.

• 1962 Aug 11 - Mercury spacecraft reaction control system test was completed.  Spacecraft: Mercury.

  Data compiled from this test was used to evaluate the thermal and thruster configuration of the Mercury extended range or 1-day mission spacecraft.

• - 1962 August-September - Mercury spacecraft configuration changes for a one-day manned orbital mission.  Spacecraft: Mercury.

  Negotiations were completed with McDonnell for spacecraft configuration changes to support the Mercury 1-day manned orbital mission. The design engineering inspection, when the necessary modifications were listed, was held on June 7, 1962.

• - By the end of 1963 - Mercury MA-11 (cancelled)  Crew: Grissom. Spacecraft: Mercury. Payload: Mercury SC12B. Launch Vehicle: Atlas D.

  From October 25, 1961 until April 1962 NASA’s Mercury program plan included four one-day flights in 1963. By October 1962 the decision had been quietly taken to limit the long-duration flights to only MA-9 and MA-10. MA-10 was fnally cancelled in turn after the successful MA-9 mission.

• Grimwood, James M., Project Mercury: A Chronology, NASA Special Publication-4001.