DISPLAYS AND CONTROLS.

    There are hundreds of controls and displays located in the cabin of the Apollo command module. A majority of these are on the main display console, which faces the three crew couches and extends on both sides of them. The console is nearly seven feet long and three feet high, with the two wings each about three feet wide and two feet deep

    The console is the heart of the command module: on it are the switches, dials, meters, circuit breakers, and other controls and displays through which the three-man crew will control the spacecraft and monitor its performance. Crew members can see and operate controls on the console while in their restraint harnesses.

    Other displays and controls are placed throughout the cabin in the various equipment bays and on the crew couches. In general, these are controls and displays that do not need frequent attention or are used during parts of the mission when crewmen can be out of the couches. Most of the guidance and navigation equipment is in the lower equipment bay, at the foot of the center couch. This equipment, including the sextant and telescope, is operated by an astronaut standing and using a simple restraint system. The non-time-critical controls of the environmental control system are located in the left-hand equipment bays, while all the controls of the waste management system are on a panel in the right-hand equipment bay. The rotation and translation controllers used for attitude, thrust vector, and translation maneuvers are located on the arms of two crew couches. In addition, a rotation controller can be mounted at the navigation position in the lower equipment bay.

    The main display console has been arranged to provide for the expected duties of crew members. These duties fall into the categories of commander, CM pilot, and LM pilot, occupying the left, center, and right couches, respectively. The CM pilot, in the center couch, also acts as the principal navigator.

(P-98) Main Display Console.

    While each astronaut has a primary responsibility, each Apollo crewman also must know all the controls and displays in the spacecraft. During a mission each might at some time take over the duties of the other crewmen: during sleep or rest periods, while other crewmen are occupied with experiments, and, of course, during an emergency.

    Flight controls are located on the left-center and left side of the main display console, opposite the commander. These include controls for such subsystems as stabilization and control, propulsion, crew safety, earth landing, and emergency detection. One of two guidance and navigation computer panels also is located here, as are velocity, attitude, and altitude indicators.

    The astronaut in the center couch (CM pilot) faces the center of the console, and thus can reach many of the flight controls, as well as the system controls on the right side of the console. Displays and controls directly opposite him include reaction control propellant management, caution and warning, environmental control and cryogenic storage subsystems.

    The right-hand ( LM pilot's) couch faces the right- center and right side of the console. Communications, electrical control, data storage, and fuel cell subsystem components are located here, as well as service propulsion of subsystem propellant management.

    All controls have been designed so they can be operated by astronauts wearing gloves. The controls are predominantly of four basic types: toggle switches, rotary switches with click-stops (detents), thumbwheels, and push buttons. Critical switches are guarded so that they cannot be thrown inadvertently. In addition, some critical controls have locks that must be released before they can be operated.

    In any mission, the Apollo crewmen will spend a great deal of their time manipulating controls and monitoring displays on the main display console. Crew duties broken down by mission phase, are determined by NASA and compiled into a checklist for each astronaut. These checklists are part of the flight data file for the mission. This file consists of ten documents divided among three packages. The two smaller packages, called data file bags, each contain two documents and are attached to the outer sides of the left and right couches at about shoulder height. The other six documents are kept in a fiberglass container stowed in the lower equipment bay.

(P-99) Astronaut stands at navigation station in lower equipment bay.

    The data file bag on the left couch contains the commander's checklist and the mission flight plan. The bag on the right couch contains the LM pilot's checklist and the mission log, which is used as a backup to the voice recorder log. The data file container includes the CM pilot's checklist, landmark maps, star charts, orbital maps an experiment checklist, and spacecraft subsystem data.

    Despite the man-hours spent in mission simulators, it would be difficult if not impossible for the astronauts to remember all the procedures required for long-duration mission. The checklists contain the detailed procedures for each phase of the mission.

    Among the checklists carried by the astronauts are those for subsystem management. These are compilations of procedures that are common to more than one phase of a mission. These procedures involve system monitoring, periodic checks, and unique functions of the service propulsion, reaction control, electrical power, environmental control, and caution and warning subsystems.

(P-100) Grouping of controls and displays.

    Periodic checks are performed from every hour to every 24 hours, depending on the subsystem, throughout a mission. In addition, other checks or tests are performed at specific times or events, such as the service propulsion subsystem tests before and after every velocity change.

CAUTION AND WARNING SYSTEM

    Critical conditions of most spacecraft systems are monitored by a caution and warning system. A malfunction or out-of-tolerance condition results in illumination of a status light that identifies the abnormality. It also activates the master alarm circuit, which illuminates two master alarm lights on the main display console and one in the lower equipment bay and sends an alarm tone to the astronauts' headsets. The master alarm lights and tone continue until a crewman resets the master alarm circuit. This can be done before the crewmen deal with the problem indicated. The caution and warning system also contains equipment to sense its own malfunctions.

(P-102) Panels and crew couches viewed through the command module hatch.