1. Orbiter Environmental Control and Life Support System

2. Orbiter ECLSS Basic Life Support Needs Pressurized gas environment Oxygen supply CO 2 removal Comfortable temperature range Comfortable humidity range Pure water supply Adequate nutrition Waste removal

3. Basic Life Support

4. Human Metabolism RequirementskgWastekg Oxygen0.84 Carbon dioxide 1.00 Food solids 0.62 Respiration & perspiration water 2.28 Water in food 1.15 Urine water 1.50 Food preparation water 0.76 Feces water 0.09 Drinking water 1.62 Sweat solids 0.02 Urine solids 0.06 Feces solids 0.03 (water subtotal) 3.53 3.87 Total mass 4.994.98

5. Orbiter ECLSS – Basic Life Support Functions Orbiter’s life support functions can support a crew of 7 for a typical mission of 10-14 days –In emergencies as many as 10 crewmembers The Orbiter can also support missions up to three weeks by carrying additional O 2, N 2 consumables, and expanded CO 2 removal –This addition is called the Extended Duration Orbiter (EDO) package Crew cabin environment is maintained within specific temperature and humidity limits –Additional limits are placed on carbon dioxide and toxic gas levels The active thermal control for the crew cabin is a combined internal/external system –Heat removal is also provided for the Orbiter's onboard electrical and avionics systems

6. Orbiter ECLSS Subsystems 1. Cabin Atmosphere –Air Revitalization System (ARS) –Atmosphere Revitalization Pressure Control System (ARPCS) –Airlock Support System 2. Active Thermal Control –Active Thermal Control System (ATCS) –Water Coolant Loop System (WCLS) 3. Food –Food Supply and Management System 4. Water supply and Wastewater system –Water supply and purification –Waste water storage and disposal 5. Waste Management –Waste Collection System (WCS) 6. Smoke Detection and Fire Suppression 7. Space Suits and EVA 8. Airlock

7. Orbiter ECLSS Schematic

8. Orbiter ECLSS Layout

9. 1. Cabin Atmosphere

10. Orbiter ECLSS - Crew Module Crew module has a total pressurized volume of 65.9 m 3 (2,325 ft 3 ) Additional pressurized areas in the cabin area are storage lockers, pressurized equipment areas, and the airlock The airlock provides an additional 4.3 m 3 (150 ft 3 ) of pressurized volume Cabin pressurization is controlled by the Atmosphere revitalization Pressure Control System –Maintained at one atmosphere (14.7 psi), except for EVA operations

11. Orbiter ECLSS - Crew Module Crew module environment Relative humidity30 - 75% Temperature 65 - 80 o F Oxygen partial pressure (PPO2)2.29 - 3.45 psi Crew cabin air flow330 ft 3 /min 7 min complete air exchange period

12. Orbiter ECLSS - Historical Habitation Volumes (NASA) Mission Duration (days) 0.1 1 10 100 1000 1 10 100 1000 Mercury Voskhod Apollo LEM Vostok Gemini STS Apollo CM Soyuz Skylab ISS Salyut 7 Mir Total Pressurized Volume (m 3 /crew)

13. Orbiter ECLSS - Orbiter Atmosphere Air Revitalization System (ARS) Resupplies O 2 and N 2, and removes CO 2, water, and contaminants

14. Orbiter ECLSS - Orbiter Atmosphere Air Revitalization System (ARS) The Orbiter's air revitalization system supplies and recirculates the O 2 + N 2 atmosphere components Controls water vapor (relative humidity) and heat within the cabin, airlock and space suits ARS also monitors and removes CO 2 and other toxic gases Filters airborne particles

15. Orbiter ECLSS - Cabin Air System

16. Orbiter ECLSS - Orbiter Atmosphere Cabin Air Revitalization Five cabin air revitalization loops are used for cooling, ventilating, and supplying air to the Orbiter's cabin Individual loops pass directly or indirectly through the cabin air system Air revitalization loops –Crew cabin (1) –Avionics bays (3) –Inertial Measurement Units (1)

17. Orbiter ECLSS - Orbiter Atmosphere Crew cabin air loop The single crew cabin air loop is designed to circulate air through the air revitalization components in the cabin air system. Responsible for removing: Heat –Removed by cabin air loop heat exchanger Moisture –Slurper bar in heat exchanger collects moisture which is pulled into dual centrifugal water separators –Removes approximately 4 lb/hr of H 2 O for typical crew –Routed to the wastewater tank Odors and trace contaminants –Removed by activated charcoal filter located in the cabin air system

18. Orbiter ECLSS - IMU Air Fan

19. Orbiter ECLSS - Orbiter Atmosphere Crew cabin air loop used to remove: CO 2 –Cabin air circulated through two lithium hydroxide (LiOH) canisters in the cabin air system –Lithium hydroxide is used because is the lightest hydroxide available, and is the least soluble –Approximately 120 lb/hr flows to each of two lithium hydroxide canisters –Each canister is rated at 48 man-hours –Up to 30 spare canisters are stored under the mid deck floor

20. Orbiter ECLSS - Orbiter Atmosphere Crew cabin air loop used to remove: CO –Ambient Temperature Catalytic Oxidizer (ATCO) unit located downstream from the cabin heat exchanger transforms CO to CO 2 by catalytic oxidation on a platinum-carbon surface –Process combines CO with O 2 which forms CO 2 which is then removed by the LiOH canisters Particles and debris –Removed by 300 micron filter in the fan circulation units

21. Orbiter ECLSS - Orbiter Atmosphere CO 2 removal Lithium hydroxide (LiOH) – canister form CO 2 removal in the Orbiter's crew cabin employs traditional lithium hydroxide canisters Used in all manned vehicles with the exception of the space stations (Skylab, Salyut, Mir, ISS) Orbiter cabin air is circulated through two LiOH canisters

22. Orbiter ECLSS - Cabin Fan and LiOH Housing

23. Orbiter ECLSS - Orbiter Atmosphere CO 2 removal - Lithium hydroxide Changed out regularly since CO 2 cannot be removed from the canisters –The lithium carbonate and water products are stable, but incapable of further CO 2 absorption Sufficient LiOH must be carried for the entire mission, plus additional canisters for possible mission extension and emergency reserve

24. Orbiter ECLSS - Orbiter Atmosphere LiOH canisters are an inexpensive solution to CO 2 removal but create a weight penalty since they retain their original mass and the absorbed mass of CO 2 and some of the respiration water Canisters are returned to Earth for disposal/refurbishment

25. Orbiter ECLSS - LiOH Replacement

26. Orbiter ECLSS - Orbiter Atmosphere CO 2 removal Regenerable Carbon Dioxide Removal System (RCRS) RCRS is used for missions longer than 16 days on orbit, or for 12 to 16 day duration missions for a crew of up to seven astronauts Carbon dioxide removal is accomplished by passing cabin air through a regenerable CO 2 removal system instead of the lithium hydroxide canisters

27. Orbiter ECLSS - Orbiter Atmosphere CO 2 removal - RCRS The regenerable system saves weight since the CO 2 and water are dumped overboard instead of absorbed in the LiOH canisters and stored for return to Earth CO 2 removal in the RCRS takes place in one of two identical solid amine resin beds –Commonly called swing beds because of their alternating use as an absorber then the desorbtion cycle –Resin combines with CO 2 and water vapor in the air to form a hydrated amine –Water is required for the process since dry amine cannot react with the carbon dioxide directly

28. RCRS

29. Orbiter ECLSS - Orbiter Atmosphere CO 2 removal - RCRS While one bed adsorbs carbon dioxide, the other bed desorbs/regenerates using a bed heater while being exposed to space vacuum – –Process removes both the CO 2 and the water from the amine granules – –Need for a vacuum vent prevents the use of the RCRS during ascent or entry – –LiOH canisters are therefore included on the RCRS flights

30. RCRS Unit – Hamilton Sunstrand

31. Orbiter ECLSS - Orbiter Atmosphere CO 2 removal - RCRS The adsorption-regeneration process in the RCRS runs continuously with the beds automatically swapped every 13 minutes –Full cycle is made up of two 13 minute cycles An RCRS configured vehicle uses a single LiOH canister for launch and another for entry –An activated charcoal canister in the other CO 2 absorber slot removes odors –Changed-out mid mission on 10+ day flights

32. Orbiter ECLSS - Orbiter Atmosphere Atmosphere Revitalization Pressure Control System (ARPCS) Controls cabin pressure

33. Orbiter ECLSS - Orbiter Atmosphere Cabin pressurization The Orbiter cabin pressure is maintained at 14.7 ±0.2 psia (or 10.5 psia for EVA) with two independent pressurization systems designated PCS 1 and PCS 2 –Total cabin pressure is regulated separately with the oxygen and nitrogen supplies, with oxygen the primary component –Nitrogen is regulated to make up the difference between the 2.95 psi oxygen pressure and the 14.7 psi total pressure –The actual oxygen pressure range limit maintained by the ARPCS is 2.95-3.45 psia

34. Orbiter ECLSS - Orbiter Atmosphere Cabin pressurization Crew respiration O 2 consumption is approximately 0.8 kg (1.76 lb) per day –Total consumption for crew respiration and cabin loss is typically 4.1 kg (9 lb) per day Oxygen is fed to the cabin from the cryogenic storage tanks that also serve as reactant storage for the fuel cells –Oxygen is supplied from the cryogenic tanks through a restrictor and heated with a small heat exchanger on the Freon coolant loop before entering the crew cabin –Maximum flow rate for cabin oxygen is 11.4 kg (25 lb) per hour is available in case of rapid cabin depressurization –Nominal ECLSS budget for the crew oxygen is 0.91 kg (2.08 lb) per man-day

35. Orbiter ECLSS - Orbiter Atmosphere Cabin pressurization Nitrogen is supplied from pressurized gas storage tanks located in the payload bay –Consumption rate of approximately 3.5 kg (7.7 lb) per day from cabin loss and venting –Regulation of the nitrogen gas by the ARPCS provides the remainder of the total cabin pressure of 14.7 psia –Nitrogen gas is also used to pressurize the water storage tanks for positive feed in microgravity

36. Orbiter ECLSS - Orbiter Atmosphere Cabin pressurization During on-orbit operations the crew cabin is supplied with a single PCS system for N 2 and O 2 –Second PCS system configured for backup –Both PCS systems are used during launch and reentry –Auxiliary tank of pressurized oxygen is also available for contingency crew cabin supply

37. Orbiter ECLSS - Orbiter Atmosphere A cabin vent valve is included in the pressurization system to equalize the cabin pressure with ambient pressure –While on the launch pad –In extreme emergencies –On orbit or during reentry for contingencies such as a cabin fire or to vent the cabin atmosphere to space through the payload bay

38. Orbiter ECLSS - Orbiter Atmosphere Cabin pressure limitations Atmosphere monitored by caution and warning system for: –Cabin pressure below 14.0 psia or above 15.4 psia –Partial pressure of oxygen (PPO2) below 2.8 psia or above 3.6 psia –Oxygen flow rate above 45 lb/hr –Nitrogen flow rate above 5 lb/hr –Cabin pressure change greater than 0.05 psi/min

39. Orbiter ECLSS - Caution and Warning Panel

40. Orbiter ECLSS - Orbiter Atmosphere Cabin pressure limitations Cabin over-pressure relief valve is set for 16 psia Positive and negative pressure relief valves in the ARPCS are used to protect the structural integrity of the cabin from over- and under-pressurization –Over-pressure relief valve opens at 15.5 psid (differential) with full flow at 16.0 psid –Under-pressure relief valve opens at -0.2 psid (ambient pressure greater than cabin pressure)

41. Orbiter ECLSS - Orbiter Atmosphere Orbiter cabin pressurization – EVA The Orbiter's crew cabin pressurization maintains a 14.7 psia atmosphere except for EVA and EVA preparation During EVA preparation the cabin pressure is reduced to 10.2 psia to minimize the risk of decompression sickness (bends) for the EVA crew –Standard protocol calls for EVA crew members to prebreathe pure O 2 before EVA to help flush N 2 form their body tissue

42. Orbiter ECLSS - Orbiter Atmosphere Orbiter cabin pressurization – EVA Three protocols (options) are available for the mission planners and crew for EVA prebreathing routines to reduce nitrogen in the blood of the EVA astronauts Option 1 60-minute initial O 2 prebreathe on launch and entry suit helmet 12 hours at 10.2 psia cabin pressure 75-minute final O 2 prebreathe in EVA suit

43. Orbiter ECLSS - Orbiter Atmosphere Orbiter cabin pressurization – EVA Option 2 60-minute initial O 2 prebreathe on launch and entry suit helmet 24 hours at 10.2 psia cabin pressure 40-minute final O 2 prebreathe in EVA suit

44. Orbiter ECLSS - Orbiter Atmosphere Orbiter cabin pressurization – EVA Option 3 4-hour O 2 prebreathe in EVA suit For scheduled EVAs, option 1 or 2 are used to minimize the in-suit O 2 prebreathe just prior to the EVA PPO 2 levels must be controlled manually during 10.2 psia cabin operations

45. 2. Orbiter Active Thermal Control System (ATCS)

46. Orbiter ECLSS - Active Thermal Control System The Active Thermal Control System removes heat from the interior of the Orbiter during all phases of the flight, from pre-launch to post-landing Operational environment extremes in temperature and temperature require three independent heat removal subsystems (sinks) –Radiator panels –Water flash evaporators –Ammonia boilers

47. Orbiter ECLSS - Active Thermal Control System

48. The Orbiter’s Active Thermal Control System uses a total of four coolant loops to remove heat from the interior of the three fuselage sections Dual-redundant interior water loops Dual-redundant exterior Freon loops Heat passage from the interior loop to the exterior loop is through a highly conductive heat exchanger

49. Orbiter ECLSS - Active Thermal Control System Heat from the interior of the Orbiter is transferred to these subsystems using dual independent water and Freon cooling loops Ground Service Equipment is used during prelaunch and post-landing to remove heat through the T-0 umbilical panel on the aft fuselage

50. Orbiter ECLSS - Active Thermal Control System Two dual-redundant cooling loops used for safe, effective heat removal Water coolant loop (cabin) Two separate internal water coolant loop systems condition the crew cabin by transferring heat from the crew cabin, avionics bays and IMUs –Heat is transferred to the dual external Freon coolant loops through a heat exchanger called the interchanger

51. Orbiter ECLSS - Active Thermal Control System Water coolant loop Two internal water coolant loops are identical, except that loop 1 has two water pumps and water loop 2 has one The separate water coolant loops are laid out side-by-side and can operate at the same time –Only one is active at any given time –Loop 2 with a single pump is normally the active loop The three water pumps are located in the ECLSS bay below the forward lockers –ATCS pumps are powered by three-phase, 115-volt ac motors

52. Orbiter ECLSS - ATCS Water Loops

54. Orbiter ECLSS - Active Thermal Control System Freon Cooling System (FCS) – external loop Freon - chlorofluorocarbon and hydrochlorofluorocarbon refrigerants used in air conditioning and refrigeration systems –DuPont products –Odorless –Colorless –Nonflammable –Noncorrosive –High thermal conductivity –High stability –Environmental hazard because of its ability to break down ozone in the upper atmosphere

55. Orbiter ECLSS - Freon Cooling System Two independent Freon-21 coolant loops designated A and B are integrated into each Orbiter Transfers heat from the Orbiter's internal water loops and external sources to the heat sinks –Freon was chosen for its efficient heat transfer, but poses a toxic gas hazard to the crew if it were to leak into the cabin module

56. Orbiter ECLSS - Freon Cooling System Dual-redundant Freon-21 systems provide system redundancy for the Orbiter's external cooling loop –Each of the two Freon loops has a pump package consisting of two pumps and an accumulator used to reduce pressure spikes at pump startup and shutdown –One pump in each loop is active at all times –A separate set of Freon loops (using Freon-40) transfers heat from the three fuel cells to the Freon-21 outer loops via the fuel cell heat exchanger

57. Orbiter ECLSS - ATCS Water Loops

58. Orbiter ECLSS - Active Thermal Control System Freon Cooling System (FCS) Avionics and electronics heat removal is accomplished with conductive cold plate networks for increased heat transfer efficiently –Forced-air cooling is used for larger electronics/avionics heat loads including the IMUs, TACAN, MSBLS, and GPCs Liquid-to-liquid heat exchangers are used to transfer heat from external cooling loops and cold plates to the external Freon 21 cooling loop pair –The two internal water cooling loops are connected to the outer Freon 21 cooling loop through the water/Freon interchanger (heat exchanger)

59. Orbiter ECLSS - ATCS Freon Loops

60. ATCS Freon Loop Pump Package

61. Orbiter ECLSS - Heat Removal Four heat sink systems are used on the Orbiter for rejecting internal heat to space/atmosphere/ground equipment 1. Radiator Panels 2. Ammonia Boiler System (ABS) 3. Flash (water) Evaporator System (FES) 4. Ground Service Equipment connections Heat is carried to these sinks via the dual internal water loops, through the water/Freon interchanger, then to the dual external Freon loops

62. Orbiter ECLSS - Heat Removal Heat removal (sinks) 1. Radiator Panels Radiation of heat to space from the Orbiter uses three panels on each of the payload bay doors in the normal configuration –Two of four radiator panels on the forward section of the payload bay doors can be extended (deployed) for increased heat rejection –Individual mission requirements determine if the forward radiators are deployed based on the heat load –The third and fourth radiator panels are fixed to the aft underside of the aft right and left payload bay doors and are not deployable

63. Orbiter ECLSS - ATCS Radiator Panels

64. Orbiter ECLSS - Heat Removal Radiator panels – Construction Radiator panels are composed of aluminum honeycomb sheet –Payload bay doors are composed of composite materials Cooling tubes that circulate the Freon 21 are located near the radiator surface Combined surface area of the radiator panels is 111 m 3 (1,195 ft 3 ) The maximum heat rejection capability of the radiator system is 61,100 Btu per hour Cold soaking the Freon that circulates in the radiators by decreasing the temperature before reentry is used as a heat sink during the later stages of reentry

65. ATCS Radiator Panels

66. Orbiter ECLSS - Heat Removal 2. Ammonia Boiler System (ABS) Ammonia boiler extracts heat from the cooling loop by the evaporation of ammonia Because ammonia has a boiling point lower than water, the ammonia evaporator is useful for primary cooling at higher ambient pressures –Primarily from reentry to landing if the radiators have not been cold-soaked –If radiator cooling is used during entry, the ammonia system is activated post-landing when the radiator outlet temperatures reach 12.8 o C (55 o F) –The ammonia boiler is also used post-landing until the Orbiter is connected to a portable GSE heat sink

67. Orbiter ECLSS - Heat Removal Each of the two Ammonia Boiler Systems located in the aft fuselage consists of: –Boiler/evaporator –Storage tank –Isolation valve –Overboard relief valve –Two control valves –Controller –Three temperature sensors –Pressure sensor –Feedline to the boiler

68. Orbiter ECLSS - Heat Removal Ammonia Boiler System (ABS) ABS heat exchanger is a single-pass ammonia and a two pass flow-through Freon coolant loop Ammonia flows over the hot Freon coolant lines in the evaporator/boiler and is vaporized

69. Orbiter ECLSS - Heat Removal Ammonia Boiler System (ABS) Heat and boiler exhaust is vented overboard in the upper aft fuselage of the Orbiter, next to the bottom right side of the vertical tail ABS contains a single boiler that is fed by two independent ammonia supply subsystems Maximum heat rejection for the ABS is 113,200 Btu/hr

70. Orbiter ECLSS - Heat Removal 3. Flash Evaporator System (FES) The FES is used to remove heat from the Orbiter's Freon-21 loops by circulating the heated Freon through the FES evaporation radiator sprayed with potable water Cooling comes from the heat of vaporization of the evaporating water vented to space –An efficient cooling process until atmospheric pressure becomes significant –Hence are used during ascent while above 140,000 feet –FES can also be used to supplement the radiator heat sink on orbit –Can also be used during deorbit and entry above approximately 100,000 feet

71. Orbiter ECLSS - Flash Evaporator System

72. Orbiter ECLSS - Heat Removal Flash Evaporator System (FES) Cold-soaking is normally used for the Orbiter's cooling during reentry and descent FES is housed in the aft fuselage Two evaporation evaporators/boilers are used in the FES –High-load evaporator has a higher cooling capacity than the topping evaporator Has only one overboard vent on the left side of the vehicle –Lower-capacity topping evaporator Has two vents that discharge steam equally to the left and right sides of the Orbiter for reactive force symmetry (non- propulsive)

73. Flash Evaporator System

74. Orbiter ECLSS - Heat Removal Flash Evaporator System (FES) FES characteristics include: 1,000 Btu per hour per lb of water consumed Maximum heat rejection is 148,000 Btu/hr using both topping and high-load evaporators Used from 125 sec after liftoff until payload bay doors are opened on orbit

75. Orbiter ECLSS - Heat Removal Flash Evaporator System (FES) Used from payload bay closure until 100,000' altitude Water supplied by potable water storage tanks A & B –Potable water is used to avoid buildup of deposits on the interior of the evaporator

76. Orbiter ECLSS - ATCS GSE 4. Ground support heat exchangers Ground support equipment is used to remove heat from the Orbiter during ground operations –Post-landing & tow-in –Orbiter Processing Facility –Vehicle Assembly Building –Rollout on Crawler to launch pad –Launch pad Portable GSE cooler used for post-landing is shown being attached to the Orbiter’s T-0 panel

77. 3. ECLSS - Food

78. Orbiter ECLSS - Food Foods supplied on STS missions are categorized as three basic types –Menu Menu foods are stocked for three meals per day Provides an average of 2,700 calories for each crewmember per day –Pantry Snacks and beverages Can be interchanged with planned menu items Make up a 2-day contingency supply Furnishes 2,100 calories per crewmember per day –Fresh Include perishable items such as fruits and vegetables

79. Orbiter ECLSS - Food Foods with a longer shelf-life are classified as: –Rehydratable (soups, casseroles, appetizers, breakfast foods) –Thermostabilized (meats, vegetables, fish, fruit) –Irradiated (meats) –Intermediate-moisture (dried fruit, dried meat) –Natural-form (nuts, granola bars, cookies)

80. Orbiter ECLSS - Food Astronauts choose their meals before the missions far enough in advance for preparation, refrigeration, and storage on the Orbiter Vitamins and minerals are included in the astronaut's individual diets according to NASA's nutritional guidelines and with the assistance of dietitians

81. Orbiter ECLSS - Food Galley A galley is provided for crew meals in the mid deck section of the Orbiter that provides: –Oven –Rehydration unit –Cold and hot water –Storage for utensils, condiments and implements –Cleanup equipment & storage

82. Orbiter ECLSS - Food Galley Traditional liquid condiments like ketchup, mustard, mayonnaise, and hot sauce are provided in familiar packets Powdered condiments like salt, pepper, and sugar are maintained in liquid form in dispensers to keep the contents from floating throughout the cabin Beverages are stored in collapsible containers and consumed using straws

83. Orbiter ECLSS - Galley

84. Orbiter ECLSS - Food Galley The galley oven and rehydration station is capable of preparing meals for the entire crew at the same time The three one-hour daily meal periods include cleanup, and waste and packaging storage, usually in the Waste Collection System Breakfast, lunch and dinner are scheduled as close to the usual meal times as possible

85. Orbiter ECLSS - Galley

86. Orbiter ECLSS - Menu Guide

87. Orbiter ECLSS - Food Individual meals are selected by each crewmember for the entire mission Stored in middeck lockers Color coded

88. 4. Water and Wastewater System

89. Orbiter ECLSS - Water & Wastewater Water onboard the Orbiter is generated by the fuel cells as potable water Used for crew consumption, crew hygiene, and for the flash evaporator cooling system –Excess water from fuel cells is normally dumped overboard, along with excess waste water –Supply water dump can also be routed through the FES as coolant if needed –Excess water can also be transferred to the International Space Station when docked

90. Orbiter ECLSS - Water & Wastewater Water is stored in five 104 liter (27.5 gal, 165 lb) tanks –Designated A, B, C, and D, and one waste water tank –Tank A is reserved for potable water for crew consumption and the first to be filled from the fuel cell supply –B, C, and D are used for excess water storage and are filled in sequence after Tank A All four of the water supply tanks can be used for the Flash Evaporator System –Tanks B, C, and D are normally used for that purpose All water tanks including waste water tank are pressurized with nitrogen gas –Drained by a bellows system

91. Orbiter ECLSS - Water Tank (Mounted as Pair)

92. Orbiter ECLSS - Water & Wastewater Water from the supply water tanks is also used to service the water supply for EMU suits in the airlock Fuel cell water production has a maximum production of 15.5 l/hr (4.1 gal/hr) –Equivalent to 0.37 kg (0.81 lb) of water per kW-hr Water lines from the fuel cells that are located in the payload bay to the tanks located in the forward fuselage are heated to prevent freezing on orbit –Water dump lines are also heated, as are the dual water dump nozzles

93. Orbiter ECLSS - Water Dump Ports & Heaters

94. Orbiter ECLSS - Water & Wastewater Hydrogen separators remove excess hydrogen from the power production process in the fuel cells before being routed to the water supply tanks Supply water is passed through a microbial filter before entering tank A –Microbial filter adds iodine compound to the water that enters tank A to prevent microbial growth in the water supply system

95. Orbiter ECLSS - Water & Wastewater Tank A water is filtered before being sent to the galley for chilled water (45-55 o F) and heated water (155-165 o F) supply Inlet valves and outlet valves on the supply water tanks allow selective fill and selective water dump –Up to 210 lb of water can be dumped at a time 76% of the water in tank A must be maintained for minimum crew requirements

96. Orbiter ECLSS - Water & Wastewater Orbiter potable water purification 0.5 ppm iodine solution added to tank A inlet Microbial filter in supply line removes small particles and microbes pH sensors monitor water purity

97. Orbiter ECLSS - Water & Wastewater Hydrogen separators remove 85% of hydrogen-rich fuel cell water –Line to Tank A passes through two hydrogen separators consisting of a matrix of silver palladium tubes which have an affinity for hydrogen 85% of hydrogen is removed then dumped overboard

98. Orbiter ECLSS - Water & Wastewater Orbiter potable water purification The waste water tank drain is not used in flight –Waste water inlet line also acts as the outlet line for dumping excess waste water overboard –A separate waste water dump line and nozzle is available, with a crossover for use by the supply tanks –A collapsible waste water bag is carried on the Orbiter in case the waste water dump nozzle is blocked

99. 5. Waste Collection System

100. Orbiter ECLSS - Waste Collection System The Orbiter's waste collection system is used primarily to collect crew fecal and urine waste in a zero gravity environment WCS base is the Orbiter commode WCS is used to: process crew cabin and EMU condensate for waste water storage Waste collection unit also routes wet trash gas for dumping overboard, transfers condensate water to the waste water tank –Facilitates condensate water overboard dumping, if necessary

101. Orbiter ECLSS - Waste Collection System The Orbiter's WCS is contained in a module that contains the waste tank, commode, and the waste management (wet and dry trash) compartment

102. Orbiter ECLSS - Waste Collection System Major components of the WCS include: Waste management compartment and privacy curtains Commode –Bag liner used for solid fecal waste storage –Vacuum exposure of bag liner is used for drying when not in use Urinal –Separate male and female adapters –Processed for storage in waste water tank Fan separators –Air flow transport for liquids in waste collection system Odor and bacteria filter –Separated air filtered and mixed with cabin air –Vacuum vent disconnect –Allows ARS waste water to be dumped overboard Waste collection controls

103. Orbiter ECLSS - Waste Collection System

104. Orbiter ECLSS Waste Collection System

105. 6. Fire Detection and Suppression System

106. Orbiter ECLSS - Smoke Detection and Suppression System Smoke detection and fire suppression components on the Orbiter are located in the crew cabin and the avionics bays Ionization detectors that sense smoke particles will trigger alarms at set concentration levels, or at concentration change limits Readouts of the smoke detectors are shown on the performance monitoring CRTs, as well as on lighted panels and on the caution and warning illuminated panels

107. Orbiter ECLSS - Smoke Detection and Suppression System Two groups of smoke sensors identified as A and B provide information on the general location –Specific ionization detector can be identified on the CRTs Group A detectors located in the ECLSS cabin fan outlet and left return duct, as well as one each in the avionics bays 1, 2, and 3 Group B are located in the right cabin return duct and the three avionics bays

108. Orbiter ECLSS - Smoke Detection and Suppression System Fire suppression on the Orbiter is divided into two areas with two separate chemicals – avionics extinguishers and crew cabin extinguishers –Freon-1301 (bromotrifluoromethane) extinguisher bottles used for the three avionics bays –Three portable extinguishers in the cabin are charged with Halon-1301 (monobromotrifluoromethane) for the crew cabin Halon-1301 is chosen for its effectiveness in controlling smoke, heat, oxygen depletion, and its ability to reduce pyrolysis products such as carbon monoxide Avionics bay extinguishers are fired by switches on the L1 panel Halon-1301 portable extinguishers are discharged manually

109. 7. Spacesuits and EVA

110. Orbiter EVA Spacewalks, or extravehicular activity (EVA), requires a self-contained, pressurized space suit that provides the same essential life support functions as the crew vehicle Space suit life support functions include: Oxygen supply Carbon dioxide removal Thermal control Odor and trace gas removal Water supply Food Waste removal

111. Orbiter EVA The crew space suit, called the Extravehicular Mobility Unit (EMU), supplies life support basics, and: –Rechargeable battery electrical power –Duplex UHF communications –Biological and instrument telemetry –Instrumentation –Caution and Warning (C/W) electronics

112. Orbiter EMU The Orbiter EMU is divided into three main parts –Hard Upper Torso (HUT) –Lower Torso assembly (LTA) –Portable Life Support System (PLSS) Many of the features and subsystems on the EMU have evolved from the earlier NASA space suits, including the self-contained PLSS, and the sublimator cooling unit that came from the Apollo- era suit

113. Orbiter EMU Typically, two EMUs are available for missions that require EVA EMUs are tailored to the astronaut and stored in the airlock except when in use on EVA Design lifetime of the EMU is 15 years

114. Orbiter EMU

115. Pure oxygen is used for suit pressurization which is maintained at 4 psid Oxygen capacity of the EMU is seven hours, with a 30 minute emergency reserve Pressurized O 2 bottles contained in the PLSS include –1.2 lb @ 8,500 psi –Secondary oxygen pack with 2.6 lb @ 6,000 psi

116. Orbiter EMU A replaceable lithium hydroxide cartridge is used for carbon dioxide removal Odor and trace gases are removed with an activated charcoal filter placed in the air/oxygen circulation line –Powered by a circulation fan

117. Orbiter EMU Major components Liquid Cooling and Ventilation Garment (LCVG) The LCVG is worn by the astronauts as an undergarment to remove excess body heat Heat removed via a network of tubes that distributes oxygen and cool water throughout the garment Water pump circulates the water through a thermal control valve assembly and sublimator

118. Orbiter EMU –Sublimator allows the passage of the warm water through channels in the porous block –As the water seeps towards the outer surface, the cold vacuum conditions in space freezes that water –Frozen water exposed to space sublimates, which cools with an equivalent heat loss of both the heat of vaporization and the heat of fusion –Liquid water is not allowed to reach the surface because of the ice formed in the outer block, which cools the liquid water flowing through the interior channels

119. Orbiter EMU Liquid Cooling and Ventilation Garment Bruce McCandless on STS-31 shown entering the Lower Torso Assembly and wearing the Liquid Cooling and Ventilation Garment

120. Orbiter EMU Hard Upper Torso (HUT) The Hard Upper Torso is the single-piece EMU rigid above-the-waist structure used to mount the space suit attachments and components that are movable, removable, or replaceable –Includes the arms, gloves, helmet, lower torso, PLSS, display and control module, and electrical harness –HUT arms contain a shoulder joint and elbow joint, along with mobility bearings in the upper arm and wrist

121. Orbiter EMU Lower Torso Assembly (LTA) The Lower Torso Assembly, roughly everything on the space suit below the waist, is attached to the Hard Upper Torso at the top and boots at the bottom LTA is composed of a number of layers that make up the flexible pants, as well as hip, knee and ankle joints

122. Orbiter EMU Portable Life Support System (PLSS) The PLSS is a fiberglass structure attached to the HUT and used to mount the internal and external components. –Fiberglass construction –Water storage bladder tanks (3) 10 lb capacity –Air circulation fan –Sublimator –Contaminant control cartridge LiOH for CO 2 removal Activated charcoal for odor & contaminant removal –Communications antenna

123. Orbiter EMU - PLSS

124. Orbiter EMU The EMU also contains power, communications, and life-support essentials that include: –Communications carrier assembly –Two UHF transmitters –Three single channel receivers –Liquid cooling and ventilation garment –Urine collection device –Operational bioinstrumentation system –Display and control module –Silver-zinc battery electrical supply

125. Orbiter EMU EMU-EVA life support duration Total duration7 hr EVA6 hr Checkout/donning15 min Doffing15 min Reserve30 min An additional 30 minutes is available from secondary oxygen supply if the primary system fails

126. Orbiter EMU - Power and Display Section

127. 8. Airlock

128. Orbiter Airlock The Orbiter's airlock assembly is used prepare two astronauts for EVA Provides for crew egress, and for their ingress in a controlled-pressure, pure oxygen environment Pressurized airlock chamber is located either in the crew cabin mid deck, or in the payload bay, depending on mission and payload requirements The 4.3 m 3 (150 ft 3 ) cylindrical airlock chamber includes two pressure hatches with windows, one on the cabin side, and one on the payload bay side Latch and gearbox assembly is placed on both sides of both hatches to allow EVA and cabin crew access to the airlock

129. Orbiter Airlock Two complete EMUs are stored in the airlock, along with a portable oxygen system Handholds, footholds and seating are furnished in the airlock for maneuvering in and out of the airlock Service connections are also provided for –Oxygen –CO 2 removal for airlock and suits –Liquid-cooled garment water –O 2 recharge for suits –Electrical power –Airlock and suit communications –Lighting

130. Orbiter Airlock

131. ECLSS Control Panel R1

134. References: NASA ECLSS Shuttle Crew Operations Manual - ECLSS, NASA NASA Food Shuttle Crew Operations Manual - Food, NASA ECLSS 21002 - Environmental Control and Life Support System Training Manual, Mission Operations Directorate, Space Flight Training & Facility Operations, Shuttle Systems Training Branch, NASA, June 1999