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There is an old adage that says "before one can learn to walk one must learn to crawl". This has been proven true for every human endeavor from building a fire to driving a car. Every step involved has to be mastered and understood before moving on to more complex tasks and achieving the end result. Human spaceflight in the 1960s was no exception to this rule. Before walking on the Moon, the men and women of Project Apollo first had to learn to crawl.
While the flight of Apollo 7 can be thought of in these terms, its complexity cannot be denied. Mission objectives were to demonstrate Command and Service Module (CSM) and crew performance; demonstrate crew/space vehicle/mission support facilities performance during a manned CSM mission; and demonstrate CSM rendezvous capability. Virtually every system on the spacecraft would be tested in primary and back-up modes throughout the mission.
The flight saw many firsts in the United States manned space flight program. It was the first manned flight of the Apollo program, the first manned launch of the Saturn IB booster, the first manned launch of the CSM, the first three-man American crew, and the first operational use of countless spacecraft systems. The mission was in every sense an "engineering test flight", providing verification of systems and procedures while paving the way for future Apollo missions.
The Apollo 7 prime flight crew included Walter M. (Wally) Schirra, Commander; Donn F. Eisele, Command Module Pilot; and Walter (Walt) Cunningham, Lunar Module Pilot. Wally Schirra was an original Mercury astronaut and the fifth American in space. This would be his third space flight having previously flown on the Sigma-7 and Gemini-6A missions. Donn Eisele and Walt Cunningham were part of the third group of astronauts selected by NASA in October 1963. Apollo 7 would be the first flight for both astronauts.
Apollo 7 lifted off from Kennedy Space Center Pad 34 at 11:02 Eastern Daylight Time, October 11, 1968. Its ride to orbit on the Saturn IB booster was normal and all systems behaved as expected. The only anomaly encountered during launch was ratty communications that would later be tracked down to improper procedures and faulty equipment on the ground.
After achieving orbit and with the crew settled in, the crew separated the spacecraft from the S-IVB second stage and performed a simulated transposition and docking. This test demonstrated the ability to dock with and extract the Lunar Module as would be required on later lunar missions. Although one of the panels on the S-IVB did not fully deploy, the techniques were verified. The panels would be jettisoned completely on later missions to avoid similar problems.
The ability of the CSM to perform a rendezvous with another object, in this case the S-IVB stage, was tested early in the flight. A phasing maneuver was performed with the Reaction Control System (RCS) to establish the conditions required for the rendezvous scheduled for one day later. During the next 6 revolutions, however, the orbit of the S-IVB decayed more rapidly than expected. A second phasing maneuver was performed with the RCS to obtain the desired initial conditions. Two Service Propulsion System (SPS) maneuvers were performed during the rendezvous to achieve the proper phase and height offset and result in an orbit coelliptic with that of the S-IVB. The onboard computer, with help from manual sightings of the S-IVB with a sextant, computed the final maneuvers required to complete a successful rendezvous.
The third day would be devoted to tests of various spacecraft systems. Test objectives for day three included a sextant calibration test, a rendezvous navigation test, an attitude control test, and a primary evaporator test.
A series of SPS maneuvers using different control modes were performed throughout the flight. A third SPS maneuver was performed on day four. This maneuver was performed earlier than planned in order to increase the backup deorbit capability of the service module RCS and resulted in moving the orbital perigee to a lower altitude over the northern hemisphere. The fourth SPS maneuver was initiated on day five to evaluate the minimum-impulse capability of the service propulsion engine. The fifth SPS maneuver was conducted on day 6 to assure verification of the propellant gauging system. It incorporated a manual thrust vector control takeover approximately half-way through the maneuver. The maneuver was targeted to position the spacecraft for an optimum deorbit maneuver at the end of the planned orbital phase. The sixth service propulsion maneuver was performed during the eighth day and was a second minimum-impulse maneuver.
The seventh service propulsion maneuver was performed on the tenth day and lasted for 7.6 seconds. This maneuver was targeted to place the perigee at the proper longitude for eventual spacecraft recovery. Hydrogen stratification and optics degradation tests were also conducted during the tenth day.
The eleventh, and final, day of the mission was devoted primarily to preparation for the deorbit maneuver. The Service Module was jettisoned, and the entry was performed using both automatic and manual guidance modes. The Command Module landed in the Atlantic Ocean near the recovery ship, USS Essex. Upon landing, the spacecraft turned over to an apex-down attitude, but was successfully returned to the normal flotation position by the inflatable bag uprighting system. The crew was retrieved by helicopter, and the spacecraft was later taken aboard the recovery ship.
For nearly 11 days and 163 orbits, the crew of Apollo 7 put the Apollo spacecraft through its paces paving the way for future missions. The Apollo 7 Mission Report states: "Almost without exception, spacecraft systems operated as intended. All temperatures varied within acceptable limits and essentially exhibited predicted behavior. Consumable usage was always maintained at safe levels and permitted introduction of additional flight activities toward the end of the mission... Even though somewhat hampered by head colds and upper respiratory congestion, the crew satisfactorily performed all flight plan functions and completed the photographic experiments." The success of Apollo 7 provided the confidence to move on to more complex missions and eventually land men on the Moon.
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