The Apollo Command Module was a critical component to the lunar missions, and the story of its development-including the tragic tale of Apollo 1—is central to understanding the story of the Apollo program.

credit:NASA

Jay Chladek

Of the many incredible machines that took America to the Moon and won the space race, one that gets less attention than it should is the Apollo capsule, or in proper parlance, the Command and Service Module (CSM).

This workhorse spacecraft was often eclipsed in many of its accomplishments by its sibling, the Lunar Module, though the CSM did garner increased attention during troubled periods, such as the Apollo 1 fire and the Apollo 13 oxygen tank explosion. But it shined during the flights of Apollo 7 and 8, during which it flew alone.

The Command Module proceeded from concept to flight in only six years, an achievement as yet unmatched in spaceflight.

THE EARLY DAYS

The history of the Apollo program actually pre-dates President Kennedy’s goal of “landing a man on the Moonand returning him safely to the Earth.” Once Project Mercury was up and running, design studies began on a follow up “multi-mission” spacecraft. Mercury would get Americans into space, and the next vehicle would allow astronauts to live and work there. The original plan was for this new craft to expand NASA’s capabilities in orbit. Over time the design project—now called Apollo—would evolve to allow astronauts to fly to lunar orbit and eventually land on the Moon’s surface. Project Gemini wouldn’t come along until 1961.

The spacecraft was designed around a crew of three, as it was felt that monitoring spacecraft systems would be a 24-hour job, with the astronauts operating in rotating shifts. The selection of a three-man crew dictated the size of the vehicle. NASA Langley engineer Maxime Faget, designer of the Mercury spacecraft, settled on a cone-shaped “blunt-body” design measuring nearly 13 feet (four meters) in diameter and 11-and-a-half feet (3.5 meters) tall. Internal living space was approximately 218 cubic feet (6.2 cubic meters); far roomier than the Mercury capsule. The shape of the Command Module (CM) and its offset center of gravity would allow the vehicle to generate lift during reentry and steer its course through the atmosphere, which would lessen the g-forces on the crew. Escape from the booster rocket in an emergency would be enabled by a set of small solid rockets suspended above the CM.