A multi-part series on the history of NASA's Apollo missions.
Apollo 7 was the first piloted test of the Command and Service Modules (CSM). The flight lasted eleven days, from October 11 – 22, 1968. Mercury and Gemini veteran Walter M. Schirra, Jr. headed the crew that included Donn S. Eisele and R. Walter Cunningham. Apollo 7 was a “shakedown” cruise for the Command and Service Modules (CSM) in Earth orbit.
The prime crew of the first manned Apollo space mission, Apollo 7, stands on the deck of the NASA Motor Vessel Retriever after suiting up for water egress training in the Gulf of Mexico. Left to right are astronauts R. Walter Cunningham, Donn F. Eisele and Walter M. "Wally" Schirra Jr. Image Credit: NASA
Astronauts Virgil I. “Gus” Grissom, Edward H. White II, and Roger B. Chaffee were supposed to perform the first piloted flight of Apollo. They were performing a practice countdown for their flight when fire broke out in their spacecraft on January 27, 1967. All three astronauts died as the flames swept through the cabin. In the aftermath, program managers and engineers scrutinized every aspect of Apollo. NASA suspended piloted flights while the spacecraft underwent major revisions.
Spacecraft changes included a quick opening hatch, the removal of flammable materials from the cabin, new spacesuits and revised test and launch procedures to improve safety. The first piloted mission with the improved Block II spacecraft, Apollo 7, was ready by the fall of 1968. Schirra, Cunningham and Eisele had been the backup crew for Grissom, White and Chaffee. They became the primary crew for the first flight.
Apollo 7 began on October 11, 1968. About 15 hours after launch, Schirra came down with a head cold. One of the physiological effects of weightlessness is the redistribution of fluids from the lower to the upper body, which can produce a feeling of nasal stuffiness, even without a cold. Microgravity made the effects of the cold even worse and Schirra was miserable. The next day, Eisele and Cunningham developed colds too, but their symptoms were not as acute.
An expended Saturn IVB stage was being used as a target for simulated docking maneuvers over Sonora, Mexico, during Apollo 7's second revolution around Earth on Oct. 11, 1968. Image Credit: NASA
Schirra became very short tempered with Mission Control. As far as he was concerned, his priority was to prove the Apollo spacecraft was capable of traveling to the Moon and back. Anything else was a distraction. Apollo 7 carried a black and white television camera. The first time they were supposed to use it, Schirra refused, citing crew workload and the need to perform more important tasks. Later in the flight they did conduct seven television transmissions.
The astronauts slept in shifts, an arrangement that was particularly hard on Eisele. He remained on watch alone while Schirra and Cunningham slept. Conversely, he was supposed to sleep while they worked. In the small confines of the Command Module, this made it nearly impossible for him to rest properly. Despite these difficulties, the astronauts met all major mission objectives. Most of the critical tests of CSM systems took place early in the mission and by the end of their second day in space the crew met 90% of the flight’s objectives. Therefore, flight controllers had them try some experiments not in the original flight plan.
Lunar module pilot Walter Cunningham writes with a space pen as he performs flight tasks on the ninth day of the mission. Image Credit: NASA
Because they were created on an ad hoc basis, these experiments were not given the typical review and practice others received. When the experiments didn’t work as smoothly as hoped, it created a sense of frustration by the astronauts and fostered a seemingly adversarial relationship with ground controllers.
One of the additional tests consisted of a series of horizon sightings using the optical sextant in the CM. This test could not be completed because the crew received erroneous instructions. Other added tests, that were successful, included evaluating different communications modes and testing spacecraft maneuverability.
Throughout the flight Schirra, Cunningham, and Eisele put the spacecraft through its paces. They performed a rendezvous with the spent upper stage from their booster; practiced aligning the craft using star sightings just as moon-bound crews would; and fired the Service Propulsion System (SPS) engine. Testing the SPS was particularly important because later crews would use the engine when they entered lunar orbit and then to send them home from the Moon.
Towards the end of the flight, the helmets became a further matter of contention between the astronauts and Mission Control. Normal reentry procedures called for the crew to wear their helmets, which meant they would not be able to manually equalize pressure within their middle ear as cabin pressure increased from 5.5 pounds per square inch in space to 14.7 pounds per square inch as they descended. Ordinarily this would not be an issue but with so much congestion from their colds, the crew feared the changes in pressure would burst their eardrums if they wore the helmets. Engineers on the ground wanted them to wear the helmets in case the cabin depressurized, but the astronauts felt the potential for damaging their eardrums was far greater than the possibility of a depressurization.
In this image, Apollo 7 commander Walter Schirra looks out the rendezvous window in front of the commander's station on the 9th day of the Apollo 7 Earth orbital mission. Image Credit: NASA
Schirra, Cunningham and Eisele completed the reentry minus their helmets without any problems. After landing, the spacecraft turned nose down in the water, which was one of its two stable modes. The astronauts righted the craft by inflating three air bags around the capsule nose. When Apollo 7 splashed down on October 22, the CSM had been thoroughly tested and passed muster. With the added experiments, NASA managers termed the flight a “101% success.”
Next month’s installment in the “Season of Apollo” series will feature the Saturn V rocket that took astronauts to the Moon.