Spacesuit Guidebook is designed to supplement Spacesuit wall chart (VVAL-114), published by the Educa- tional Affairs Division, January 1990. The wall chart depicts Astronuat Bruce McCandless on his historic first untethered spacewalk using the Manned Maneuvering Unit. He flew on Shuttle mission 41 -B (February 3-1 1, 1984), and ventured 100 meters from the Shuttle's cargo bay and returned safely. The guidebook explains in depth the elements depicted on the wall chart in see-through and cut-away perspectives. Together the wall chart and guidebook show as well as explain the inside workings of the spacesuit and its various components. Forty separate elements are identified with an accompanying numerical legend. Those elements are further ex- plained in this guidebook along with their functions and how they work in relation to other elements. Additional chapters discuss essential compo- nents of the spacesuit such as the Primary Life Support System and the Manned Maneuvering Unit, and the method for donning the spacesuit. The original manuscript for this guidebook was written by Greg Vogt, Oklahoma State University. It was expanded and edited into this format by Robert Haynes, NASA Headquar- ters. The oil painting, around which the wall chart was designed, was painted by American artist Bruce Wolfe. Many people assisted in reviewing this guidebook from the early stages up to the final booklet. Special thanks go to Keith Hudkins, NASA Headquarters, for identifying the 40 spacesuit components; and to James Poindexter, Johnson Space Center for reviewing the manuscript. pacesuit components The EMU is what Space Shuttle systems. Items 1 and 2 are explained around y axis), pitch (z axis), and astronauts call their spacesuit. EMU more fully in their own chapters. yaw (x axis). stands for Extravehicular Mobility 1. Primary Life Support System 3. Thruster Lights Unit. It is what protects astronauts This portable life support system While flying the Manned Maneu- from the harsh environment of space is an essential component of the vering Unit, the astronaut keeps outside the Space Shuttle's crew spacesuit. It is the backpack unit track of propellant with two cabin. The EMU includes many that the astronaut is wearing (it is gauges located on either side of individual components that, when only partially visible in the paint- the helmet's face plate. An assembled, form a single spacesuit. ing, shown on either side of the astronaut needs to know how Making the EMU is an exacting astronaut's helmet). The life much propellant is left in the unit, process. Pressure and restraint layers support system contains all the because when the propellant is are enclosed by thermal insulating control and monitoring systems gone, the astronaut is no longer and tear and puncture resistant layers. required to sustain the astronaut's able to maneuver. The astronaut One layer's function is just to keep the life while in space. It supplies needs to keep enough fuel in astronaut from overheating. Suit oxygen for breathing and for suit reserve to return safely to the layers are joined to metal connecting pressurization, and cleans carbon Shuttle. Generally, this means an rings and a hard fiberglass upper dioxide and odors from the air astronaut can use up half the fuel torso. Each layer and each compo- inside the suit. A tiny built-in to maneuver away from the nent must pass stringent inspections computer warns the astronaut of Shuttle and keep the remaining before a human life is entrusted to it. problems. half for the return. When fully assembled, the EMU 2. Manned Maneuvering Unit 4. Extravehicular Mobility Unit becomes a nearly complete short- Thruster Lights term, "soft," spacecraft for one A series of 24 thrusters is located EMU lights are found on either person. It provides pressure, thermal, on the Manned Maneuvering Unit side of the astronaut's helmet and and micrometeoroid protection, (MMU). The astronaut controls are used to shine light on objects oxygen, cooling water, drinking water, them with hand controllers at the in space. The small built-in flood food, waste collection (including ends of the MMU's two arms. lamps light up places sunlight and carbon dioxide removal), electrical (See item 40.) The thrusters may lights in the cargo bay do not power, and communications. The also be operated automatically by reach. The EMU lights have their only thing lacking in the EMU is pro- turning on an automatic attitude own battery system and are pulsion, but this can be added by hold system. Compressed nitro- needed for work in the Shuttle fitting a gas-jet-propelled Manned Ma- gen is moved through feed lines cargo bay or for repairing satel- neuvering Unit. On Earth the suit and to varying combinations of the 24 lites in space. When the astro- all its parts weigh about 112 kilo- nozzles. The nozzles are arranged nauts are building the Space grams. In orbit, they have no weight in clusters of three each on the Station Freedom, the EMU lights at all, but do retain their mass, which eight corners of the maneuvering will help them assemble the astronauts feel as a resistance to a unit, and are aimed along three pieces of the Station while in orbit change in motion. axes perpendicular to each other above Earth. The list that follows corresponds (x, y, and z) and permit six de- 5. Color Television Camera to the numerical legend on the wall grees of freedom of movement. The camera's lens system is chart. Some items will be self-ex- Movements in space are ex- about the size of a postage stamp, planatory, while others are parts of plained by the terms roll (rotation and mounted just over the helmet. Television monitoring is neces- Communications Microphone power from the Shuttle itself. In sary for certain communications Voice communication with the this manner the "consumables" with the Shuttle and Mission Shuttle and Mission Control are stored in the Primary Life Sup- Control. The camera is situated essential at all times. The micro- port System are conserved in line of view with the astro- phone inside the helmet con- during the prebreathing activity naut's own line of vision and is nects to the radio module located that is needed before an astro- equipped with its own batteries in the life-support unit of the naut can leave the Shuttle crew and RF transmitter so that the spacesuit. Covering the astro- cabin. The umbilical remains crew inside the Shuttle and naut's head is the communica- connected to the spacesuit until mission controllers on Earth can tions carrier assembly, or the astronaut disconnects it after get an astronaut's eye view of the "Snoopy Cap" as it is sometimes moving from the airlock into the spacewalk. During complicated called. The assembly is a fabric cargo bay. At the time the spacewalks, viewers may be able skull cap with built-in earphones umbilical is released, the space- to provide assistance. and a microphone for use with walk begins. The Service and 6. Helmet Solar Shield the spacesuit's radio. Cooling Umbilical is also used to Shown in the wall chart as a cut- 35mm Still Camera recharge batteries and replenish away, the solar shield is actually Views of the Shuttle, its cargo consumables. part of an entire assembly that bay, satellites, Earth, and other 11. Emergency Relief Valve covers the helmet. The visor as- phenomena are captured for Should the Primary Life Suport sembly contains a metallic gold- study by the 35mm camera. The System malfunction, the astro- coated Sun-filtering visor, a clear camera is attached to the naut can survive for 30-60 thermal impact protection visor, Manned Maneuvering Unit and is minutes by using the secondary and adjustable blinders that situated in line of view with the oxygen pack (see chapter 3, attach over the helmet. These astronaut's own line of vision. "Primary Life Support System"). shields are necessary to protect Camera Switch This system is activated by astronauts from harmful light The 35mm still camera is oper- opening the purge valve. This and radiation emitted by the Sun. ated by a cabled switch con- valve, which has a set of pinch- The helmet itself is a plastic nected to the camera and the ers on either side of it, allows the pressure bubble with a neck dis- glove of the EMU. The astronaut astronaut to let some of the connect ring and ventilation merely needs to press a button pressure out of the EMU. To distribution pad. The helmet has on the end of the cable attached activate the valve, the astronaut a backup purge valve (for use to his or her glove, and the simply squeezes the pinchers with a secondary oxygen pack camera automatically focuses, with the EMU glove, and air worn beneath the Primary Life snaps the picture, and advances pressure is released through the Support System backpack) and the film for the next picture. tube-like extension on the EMU is used to remove expired carbon Spacecraft Life-Support chest plate. dioxide. (See item 11.) A tube Connector 12. Water Cooling Control Valve projects into the helmet near the Long before donning the upper The astronaut is able to control astronaut's mouth from a plastic half of the EMU, the Shuttle's his or her body temperature water pouch attached inside the Service and Cooling Umbilical is inside the spacesuit by control- spacesuit's hard upper torso. plugged into the dispays and ling the temperature of water cir- The tube allows the astronaut to control module panel on the culating through the Liquid drink from it as if from a straw, front of the upper torso.