Space Shuttle

Space Shuttle - Development Problem: NASA’s Apollo missions, although spectacular, required dedicated vehicles with limited utility for other space exploration projects. The best example of that limitation was the Huge Saturn V that was best suited for lunar missions. A solution to the problem of space access for research, academia, industry, and other agencies was thought to lie in replacing expendable vehicles with reusable launchers. NASA’s solution: Develop a universal, reusable booster that could be used for all space flight missions - from orbital satellites to deep space exploration

Space Shuttle - Development One possible solution: A DynaSoar-like manned glider launched on an inexpensive expendable booster like the Titan or Atlas Problem 1: The USAF needed heavy-lift capability and a high-lift reentry vehicle for its surveillance programs Problem 2: Budget limitations mandated a combined NASA-USAF launch vehicle

Space Shuttle - Development Proposed solution to Congress: Replace all expendabl e boosters with a single, reusable, versatile booster

Space Shuttle - Development NASA’s solution approved by Congress: Develop a large universal booster for all space flight missions - military, orbital and deep space USAF requirement 1: a 15’ x 60’ payload capacity USAF requirement 2: Winged vehicle with sufficient reentry lift to provide a 1,500 mi cross-range capability (land at alternate sites and/or land after 1 orbit)

Space Shuttle - Development Ballistic vehicles produce little lift but high heating. Winged (high lift) vehicles reduce retentry forces, but increase total heating but with a lower max temp. Mercury, Gemini, Apollo capsules are in between.

Space Shuttle - Development NASA’s ultimate solution: Large, versatile, reusable booster useful for all space flight missions with a 15’ x 60’ payload capacity and a winged reentry vehicle with a 1,500 mi cross-range capability. First approximation: A large lifting body similar to those tested in the 1950s and early 1960s (X-24 and HL-10 gliders shown below), but with added boosters.

Space Shuttle - Development Early design concepts

Space Shuttle - Development Early design concepts Lockheed Star Clipper

Space Shuttle - Development Early design concepts Chrysler reusable launcher and orbiter

Space Shuttle Early design concepts Martin Marietta dual fly-back booster and orbiter

Space Shuttle - Development Early design concepts Sketch of processing operations envisioned at KSC circa 1969

Space Transportation System Final Design

Space Shuttle - Development Design concept and approval for NASA Space Transportation System (STS) was completed in Reusable Orbiter with 15’ x 60’ payload bay 2. Additional propulsion engines attached to the Orbiter 3. External tank to carry propellants 4. Solid rocket boosters for majority of lift on first stage

Space Shuttle - Development Contracts for the STS were awarded in

Space Shuttle mission configuration

Space Shuttle Orbiter

Reusable winged reentry vehicle Composition – Aluminum alloy similar to commercial aircraft Structure - 122' long, 57' high, 78' wingspan Launch weight - approximately 230,000 lb Cargo bay - 15' x 60' Design lifetime flights Crew – 5 to 7 (10 max for emergencies)

Space Shuttle Orbiter 3 major sections 9 major components

Space Shuttle Orbiter 9 major components 1. Forward fuselage - the top and bottom sections which surrounds the crew compartment 2. Wings - aluminum alloy structure that include elevons for longitudinal control 3. Mid fuselage - 60 ft midsection that is the primary load carrying structure 4. Payload bay doors - graphite epoxy for light weight 5. Aft fuselage - truss-type structure that transfers SSME thrust to mid fuselage and ET 6. Forward Reaction Control System (RCS) 7. Vertical tail - aluminum alloy structure that includes combine rudder and speed brake 8. OMS/RCS systems OMS - Orbital Maneuvering System used to change or alter orbit (higher thrust than RCS) RCS - Reaction Control System is used for spacecraft attitude control 9. Body flap - protect SSMEs during reentry and help provide aerodynamic control

Space Shuttle Orbiter

Solid Rocket Boosters

Space Shuttle Solid Rocket Boosters (SRBs) Reusable, solid fuel booster pair provides 72% of liftoff thrust Structure – 4 motor sections + recovery frustum Structure – 4 motor sections + recovery frustum Length – 149.2’ Length – 149.2’ Diameter – 12.2’ Diameter – 12.2’ Weight – 1,300,000 lb loaded Weight – 1,300,000 lb loaded Thrust – 3,300,000 lb f Thrust – 3,300,000 lb f Burn time – 2 min 10 sec Burn time – 2 min 10 sec Propellant – aluminum powder (fuel) + ammonium perchlorate (oxidizer) Propellant – aluminum powder (fuel) + ammonium perchlorate (oxidizer) I sp – 269 sec I sp – 269 sec Boost altitude – 150,000’ Boost altitude – 150,000’ Recovery – parachute + floatation devices Recovery – parachute + floatation devices

Space Shuttle Solid Rocket Boosters

SRB Segments - Assembly SRBs are bolted to the Mobile Launcher Platform inside the Vehicle Assembly Building (VAB)

SRB Fuel SRB solid fuel composition Ammonium perchlorate (oxidizer) 69.6% Ammonium perchlorate (oxidizer) 69.6% Powdered aluminum (fuel) 16% Powdered aluminum (fuel) 16% Iron oxide (catalyst) 0.4% Iron oxide (catalyst) 0.4% HTPB polymer binder 12% HTPB polymer binder 12% Epoxy curing agent 2% Epoxy curing agent 2%

Space Shuttle Main Engines

SSMEs - Operations The Space Shuttle Main Engine (SSME) is a dual-stage (staged), regeneratively cooled (circulated propellant), reusable, variable thrust, high-performance, LOX + LH2 rocket engine with thrust vectoring using hydraulic actuators Each SSME is performance rated and assigned duty for specific missions based on the vehicle performance requirements (primarily the payload mass and orbital inclination) and engine performance parameters All three engines selected for a mission are matched for comparable performance

SSMEs

Space Shuttle Main Engines (SSME) Reusable, single-start liquid bipropellant engines Length – 14’ Length – 14’ Diameter – 7.5’ Diameter – 7.5’ Weight – 7,480 lb Weight – 7,480 lb Thrust – 513,250 lb f (109% in space/vacuum) Thrust – 513,250 lb f (109% in space/vacuum) Burn time – 8 min Burn time – 8 min Propellants Propellants Liquid hydrogen Liquid hydrogen Liquid oxygen Liquid oxygen I sp – 452 sec I sp – 452 sec Lifetime – 100 starts (7.7 hr accumulated operational time) Lifetime – 100 starts (7.7 hr accumulated operational time) Mixture ratio – 6:1 Mixture ratio – 6:1

Space Shuttle Main Engine (SSME)

External Tank

Space Shuttle External Tank The Space Transportation System’s External Tank is one of the four major components that was contracted for development and production by NASA in 1972 Lockheed-Martin won the ET contract and moved its fabrication plant to the NASA facilities in Machoud, Louisiana Lockheed-Martin won the ET contract and moved its fabrication plant to the NASA facilities in Machoud, Louisiana The Machoud plant’s location on the Gulf of Mexico allowed shipping the completed External Tanks to the Kennedy Space Center by barge The Machoud plant’s location on the Gulf of Mexico allowed shipping the completed External Tanks to the Kennedy Space Center by barge The ET is the largest component on the STS, and could not be shipped by rail or by cargo aircraft The ET is the largest component on the STS, and could not be shipped by rail or by cargo aircraft The Machoud plant will be turned over to Boeing for conversion into the upper-stage Ares I fabrication facility as the STS project comes to an end The Machoud plant will be turned over to Boeing for conversion into the upper-stage Ares I fabrication facility as the STS project comes to an end

Space Shuttle External Tank Super-lightweight aluminum-lithium dual tank and thrust structure (non-reusable) Length – 154.2’ Length – 154.2’ Diameter – 27.5’ Diameter – 27.5’ Weight Weight 1,668,000 lb loaded 1,668,000 lb loaded 78,100 lb empty 78,100 lb empty LOX weight – 1,359,000 lb LOX weight – 1,359,000 lb LH2 weight – 226,000 lb LH2 weight – 226,000 lb

ET Transportation Fabricated External Tanks are placed on a barge in the Michoud, Louisiana plant ant towed to the Kennedy Space Center by tug

ET – The Future NASA Ares I and Ares V vehicles were to employ similar tanks to the ET LH2-LOX structure Ares I is the cargo launcher consisting of a 5-segment SRB, with an upper liquid fuel booster Ares I is the cargo launcher consisting of a 5-segment SRB, with an upper liquid fuel booster LH2 & LOX propellants LH2 & LOX propellants Approximately 1/5 the volume of the STS ET Approximately 1/5 the volume of the STS ET Uses only spray-on insulation since crew vehicle rides on top of the booster Uses only spray-on insulation since crew vehicle rides on top of the booster No insulation shedding hazard No insulation shedding hazard Ares V uses two 5-segment SRB boosters with 5 RS-68 second- stage engines Ares V uses two 5-segment SRB boosters with 5 RS-68 second- stage engines RS-68 are used on the Delta IV RS-68 are used on the Delta IV Second-stage uses the same ET structure with separate LH2 and LOX tanks separated with an intertank structure Second-stage uses the same ET structure with separate LH2 and LOX tanks separated with an intertank structure

Launchers – Past, Present, and Future

Passive Thermal Protection System

Orbiter Thermal Protection System Orbiter TPS - Refractory coated glass tiles Reinforced Carbon-Carbon (RCC) - Used on the nose cap and wing leading edges where reentry temperatures exceed 1260° C (2300° F) Reinforced Carbon-Carbon (RCC) - Used on the nose cap and wing leading edges where reentry temperatures exceed 1260° C (2300° F) High-temperature Reusable Surface Insulation (HRSI) - Used primarily on the Orbiter belly where reentry temperatures are below 1260° C High-temperature Reusable Surface Insulation (HRSI) - Used primarily on the Orbiter belly where reentry temperatures are below 1260° C Fibrous Refractory Composite Insulation (FRCI) - FRCI tiles that have replaced some of the HRSI 22 lb tiles provide improved strength, durability, resistance to coating cracking Fibrous Refractory Composite Insulation (FRCI) - FRCI tiles that have replaced some of the HRSI 22 lb tiles provide improved strength, durability, resistance to coating cracking Toughened Unipiece Fibrous Insulation (TUFI) - A stronger, more durable tile that is replacing high and low temperature tiles in high- abrasion areas Toughened Unipiece Fibrous Insulation (TUFI) - A stronger, more durable tile that is replacing high and low temperature tiles in high- abrasion areas Low-temperature Reusable Surface Insulation (LRSI) - Originally used on the upper fuselage, but now mostly replaced by AFRSI Low-temperature Reusable Surface Insulation (LRSI) - Originally used on the upper fuselage, but now mostly replaced by AFRSI

Orbiter Thermal Protection System Orbiter passive thermal tile types Fibrous blankets Advanced Flexible Reusable Surface Insulation (AFRSI) - Quilted, flexible surface insulation blankets used where reentry temperatures are below 649° C (1200° F) Advanced Flexible Reusable Surface Insulation (AFRSI) - Quilted, flexible surface insulation blankets used where reentry temperatures are below 649° C (1200° F) Felt reusable surface insulation (FRSI) - Nomex felt blankets that are used on the upper regions of the Orbiter where temperatures are below 371° C (700° F) Felt reusable surface insulation (FRSI) - Nomex felt blankets that are used on the upper regions of the Orbiter where temperatures are below 371° C (700° F)

TPS Surfaces Lower Surface Upper Surface TPS Legend HRSI (Black) Tiles LRSI (White) Tiles AFRSI Blankets Glass Exposed Metallic Surfaces FRSI RCC

Bonded TPS HRSI tiles on the Orbiter ~19,700 (9 lb), 525 (22 lb) TUFI tiles on the Orbiter 306 (8 lb) FRCI tiles on the Orbiter 2,950 (12 lb) LRSI tiles on the Orbiter 725 (9 lb), 77 (12 lb) FIB blanket area on the Orbiter 2,123 sq ft FRSI sheet area on the Orbiter 2,024 sq ft

Electrical Power System

Orbiter EPS Electrical power for the Orbiter is provided by three fuel cells powered by liquid hydrogen and liquid oxygen Electrical power for the Orbiter is provided by three fuel cells powered by liquid hydrogen and liquid oxygen Fuel cells for manned spacecraft were first used in the Gemini program Fuel cells for manned spacecraft were first used in the Gemini program Developed for the Apollo missions because of their byproduct – water Developed for the Apollo missions because of their byproduct – water Weight savings from not carrying water was a greater advantage than the disadvantages of the added weight, volume and complexity of the cryogenic reactant storage Weight savings from not carrying water was a greater advantage than the disadvantages of the added weight, volume and complexity of the cryogenic reactant storage To improve the electrical power system (EPS) efficiency and reliability, the Orbiter’s fuel cell system was designed to power the entire STS To improve the electrical power system (EPS) efficiency and reliability, the Orbiter’s fuel cell system was designed to power the entire STS

EPS

EPS – Fuel Cells Fuel cell advantages over conventional spacecraft power Water byproduct Water byproduct Efficient conversion of reactant mass into electrical energy Efficient conversion of reactant mass into electrical energy High power output (7-10 kW per cell) High power output (7-10 kW per cell) Power output is dependent only on load requirements (small standby power needed) Power output is dependent only on load requirements (small standby power needed)

EPS – Fuel Cells Fuel cell advantages over conventional spacecraft power Modular components could be replaced as necessary (during processing, not on orbit) Modular components could be replaced as necessary (during processing, not on orbit) Vibration and noise free operation Vibration and noise free operation Low maintenance required during mission operations Low maintenance required during mission operations Relatively low weight Relatively low weight Liquid oxygen was also required for crew life support Liquid oxygen was also required for crew life support

EPS – Fuel Cells Each fuel cell is connected to an independent, isolated dc bus Each fuel cell is connected to an independent, isolated dc bus All three buses have cross-ties All three buses have cross-ties Crossover circuits are also provided for a number of the subdivided buses Crossover circuits are also provided for a number of the subdivided buses Alternating current is generated on three independent ac buses connected to the three main dc bus lines Alternating current is generated on three independent ac buses connected to the three main dc bus lines

Orbital Maintenance System (OMS) and Reaction Control System (RCS)

OMS/RCS System Flight control of the Orbiter beyond the atmosphere is provided by the OMS and RCS thrusters OMS/RCS functions are under the control of the operational software used for Guidance Navigation and Control (GN&C) The OMS and RCS thrusters are combined to furnish both high and low thrust for the Orbiter’s two flight functions on orbit Orbit change - OMS Orbit change - OMS Attitude control - RCS Attitude control - RCS

OMS/RCS System

Both OMS and RCS thrusters use the same propellants Monomethyl hydrazine – fuel Monomethyl hydrazine – fuel Nitrogen tetroxide – oxidizer Nitrogen tetroxide – oxidizer Thruster placement OMS – Only aft thrusters OMS – Only aft thrusters RCS – Both fore and aft thrusters RCS – Both fore and aft thrustersThrust OMS thrusters OMS thrusters 6,000 lb (2) 6,000 lb (2) RCS thrusters RCS thrusters 870 lb (38) 870 lb (38) 24 lb (4) 24 lb (4)

Communications System

Orbiter Communications UHF (voice) Duplex and simplex S-band (data and voice) Duplex Ku-band – video data Duplex

Orbiter Communications Data Types Telemetry Downlink data of the Orbiter's operating conditions and configurations, systems, payloads and crew biotelemetry measurements Telemetry Downlink data of the Orbiter's operating conditions and configurations, systems, payloads and crew biotelemetry measurements Command Uplink data directed to the Orbiter systems to perform functional or configuration changes Command Uplink data directed to the Orbiter systems to perform functional or configuration changes Rendezvous and tracking Onboard radar and communications system for tracking and performing rendezvous with orbiting satellites/spacecraft Rendezvous and tracking Onboard radar and communications system for tracking and performing rendezvous with orbiting satellites/spacecraft Video Video Video imaging is used onboard, or relayed to ground from the crew cabin or on EVA activities, or from the payload bay, or from the remote manipulator arm Voice communications Intracommunications between the flight crew members, and between the flight crew and ground Voice communications Intracommunications between the flight crew members, and between the flight crew and ground Documentation Printed data from the Orbiter's thermal impulse printer system (TIPS) Documentation Printed data from the Orbiter's thermal impulse printer system (TIPS)

Orbiter Communications Data Types The Orbiter communications system bands include 1. S-band 1. S-band PM (Phase Modulation) PM (Phase Modulation) FM (Frequency Modulation) FM (Frequency Modulation) Payload Payload 2. Ku-band TDRSS data & video communications TDRSS data & video communications Rendezvous radar Rendezvous radar 3. UHF voice Ground Ground EVA EVANote: Voice communications are also available through the military TACAN unit Other frequencies are used for the Orbiter's navigation subsystems and include C-band for the radar altimeter, L-band for the GPS and TACAN units, and Ku-band for the MSBLS landing system Other frequencies are used for the Orbiter's navigation subsystems and include C-band for the radar altimeter, L-band for the GPS and TACAN units, and Ku-band for the MSBLS landing system

Command and Data Handling System

Command & Data Handling System The Orbiter functions and operations are managed by a computerized data management system called the Command and Data Handling System Primary data management is provided by five identical IBM 101 digital computers running in parallel for redundancy Primary data management is provided by five identical IBM 101 digital computers running in parallel for redundancy Secondary data management is furnished by a network of 24 computerized system management units called Multiplexers/Demultiplexers (MDMs) Secondary data management is furnished by a network of 24 computerized system management units called Multiplexers/Demultiplexers (MDMs) Two dedicated critical event control units supply signal and data management for launch, orbit, deorbit, and landing phases of the Orbiter and STS Two dedicated critical event control units supply signal and data management for launch, orbit, deorbit, and landing phases of the Orbiter and STS Two tape drives containing command and data programs are also provided for redundancy in flight operation software Two tape drives containing command and data programs are also provided for redundancy in flight operation software

C&DH functional block diagram

Command & Data Handling System – MEDS Glass Cockpit A full glass cockpit was introduced to the Orbiter lineup with the installation of the complete upgrade of Atlantis to a digital cockpit display with 11 full-color flat panel screens First mission of Atlantis with the glass cockpit was an assembly flight to the ISS on STS-101 in May, 2000 First mission of Atlantis with the glass cockpit was an assembly flight to the ISS on STS-101 in May, 2000 Each of the four Orbiters has been upgraded to a Multifunction Electronic Display System (MEDS) glass cockpit Each of the four Orbiters has been upgraded to a Multifunction Electronic Display System (MEDS) glass cockpit

Fish-eye view of the Orbiter's new Multifunction Electronic Display Subsystem (MEDS) glass cockpit shown here in the Johnson Space Center's Shuttle Mission Simulator

Command & Data Handling System – Portable Computers Laptop computers were flown for the first time on the Endeavour Orbiter on the first Hubble Space Telescope servicing mission during STS-61 The first Shuttle IBM ThinkPad 750C laptops were replaced with the IBM 755C ThinkPad in 1994 to become a standard Space Shuttle Payload and General Support Computer (PGSC) for astronaut and experiment use The first Shuttle IBM ThinkPad 750C laptops were replaced with the IBM 755C ThinkPad in 1994 to become a standard Space Shuttle Payload and General Support Computer (PGSC) for astronaut and experiment use Later replacements to the Shuttle laptop computers includes the IBM ThinkPad 760XD and a Rendezvous and Proximity Operations Program (RPOP) software package to aid in docking and rendezvous operations with the International Space Station Later replacements to the Shuttle laptop computers includes the IBM ThinkPad 760XD and a Rendezvous and Proximity Operations Program (RPOP) software package to aid in docking and rendezvous operations with the International Space Station

Space Shuttle Processing

STS processing is a term used to describe the preparations and procedures for readying the Space Shuttle for its next mission The STS processing work cycle begins with the Orbiter’s return to KSC for its coming flight The STS processing work cycle begins with the Orbiter’s return to KSC for its coming flight The processing cycle actually starts with the development of the flight, equipment, and operations manifest The processing cycle actually starts with the development of the flight, equipment, and operations manifest Planning begins as early as 5 years before the planned mission, or in some cases even longer Planning begins as early as 5 years before the planned mission, or in some cases even longer

Space Shuttle Processing Primary processing facilities are at KSC Primary processing facilities are at KSC Supporting facilities include Supporting facilities include Other KSC sites (transportation, logistics, etc.) Other KSC sites (transportation, logistics, etc.) JSC JSC NASA Center – Washington, D.C. NASA Center – Washington, D.C. NASA Centers NASA Centers Primary contractors – worldwide and national Primary contractors – worldwide and national Federal agencies (FAA, NTSB, DoD, etc.) Federal agencies (FAA, NTSB, DoD, etc.) State agencies State agencies Local contractors Local contractors Educational institutions Educational institutions Media services Media services

Space Shuttle Processing Facilities

Space Shuttle Processing

STS Assembly & Integration

STS Assembly Assembly base - the Mobile Launcher Platform The Mobile Launcher Platform (MLP) was originally designed and used for the Apollo- Saturn V missions The Mobile Launcher Platform (MLP) was originally designed and used for the Apollo- Saturn V missions MLP has similar tail service masts that are used for umbilical connections between the Ground Service Equipment and the launch vehicle MLP has similar tail service masts that are used for umbilical connections between the Ground Service Equipment and the launch vehicle These protective covers and connections swing away from the vehicle just before liftoff These protective covers and connections swing away from the vehicle just before liftoff

STS Assembly – SRB Stacking The completed pair of boosters is then mated with the External Tank at the fore (top) and aft (bottom) attach points that use a similar bolt and frangible nut pair as the aft skirt hold down posts The completed pair of boosters is then mated with the External Tank at the fore (top) and aft (bottom) attach points that use a similar bolt and frangible nut pair as the aft skirt hold down posts Further assembly and checkout of the SRB is completed during the mate of the Orbiter, and finally at the launch pad Further assembly and checkout of the SRB is completed during the mate of the Orbiter, and finally at the launch pad

STS Assembly – ET After preparation, the External Tank is then demated from the transporter, rotated, then lifted vertically into the high bay and mated with the stacked SRB pair Total time for the ET checkout and preparation is approximately 70 days

STS Assembly Orbiter Attachment This begins with the Orbiter's attachment to the External Tank, which itself has been attached to the SRB This begins with the Orbiter's attachment to the External Tank, which itself has been attached to the SRB Structural isolation of the SRB from the Orbiter is necessary because of the separation sequence during the ascent phase of flight, and because of design requirements Structural isolation of the SRB from the Orbiter is necessary because of the separation sequence during the ascent phase of flight, and because of design requirements

STS Assembly Orbiter lift After passing over the high bay transom, the Orbiter is lowered near the External Tank for attachment After passing over the high bay transom, the Orbiter is lowered near the External Tank for attachment As the Orbiter attains the correct alignment with the ET, the lift is halted and the attachment procedures begin As the Orbiter attains the correct alignment with the ET, the lift is halted and the attachment procedures begin Orbiter attachment (integration) takes approximately 5 days Orbiter attachment (integration) takes approximately 5 days

STS Assembly Completion Rollout The nearly- completed STS mounted on the Mobile Launcher Platform (MLP) is carried out the the launch pad by the Crawler Transporter The nearly- completed STS mounted on the Mobile Launcher Platform (MLP) is carried out the the launch pad by the Crawler Transporter

STS Assembly Completion Some of the separation ordinance is installed in the vehicle and checked, but not wired into the firing circuitry of the Master Events Controller Some of the separation ordinance is installed in the vehicle and checked, but not wired into the firing circuitry of the Master Events Controller Final connection and testing for the pyro components are made as the Shuttle vehicle goes through its final launch preparation on the pad Final connection and testing for the pyro components are made as the Shuttle vehicle goes through its final launch preparation on the pad

STS Launch Preparations Preparations for launch of the STS on the launch pad take approximately one month Countdown begins three days before launch

The Launch