A JOURNEY INTO SPACE How Rocket s Work
HOW ROCKETS WORK CONTENTS
C H A PT E R 1 - D E F I N I T I O N What is a Rocket?
P . 05
C H A PT E R 2 - H I STO RY Ancient Rocketry
P . 08
Early Rocketry
P . 10
Modern Rocketry
P . 14
Future Plans
P . 17
C H A PT E R 3 - T Y P I C A L RO C K E T P L A N Atlas Centaur
P . 19
Satellite Launch Procedure
P . 20
C H A PT E R 4 - N A SA S PAC E S H U T T L E The Rocket that keeps coming back
P . 24
How the Shuttle works
P . 26
C H A PT E R 5 - S H U T T L E ST R U C T U R E Pressurized Crew Module Altitude Control Systems Propulsion
P . 33 P . 35 P . 36
C H A PT E R 6 - B L A STO F F From Earth to Space
P . 40
C H A PT E R 7 - D E S C E N T From Orbit to Earth
P . 44
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CHAPTER 1 DEFINITION
What is a rock路et? A cylindrical projectile that can be propelled to a great height or distance by the combustion of its contents, used typically as a firework or signal.
The word "rocket" can mean different things. Most people think of a tall, thin, round vehicle. They think of a rocket that launches into space. "Rocket" can mean a type of engine. The word also can mean a vehicle that uses that engine to push itself forward in a vaccum.
Rockets in our case is a vehicle for transport. It functions as a vessel to carry people, equipment, fuel, food, and space station parts from earth and into orbit around our beloved planet Earth. Rockets can also travel through space and to other planets and their moons.
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CHAPTER 2 HISTORY
1687
NEWTONS LAWS OF MOTION
For every action, there is an equal and opposite reaction.
1946
ATMOSPHERIC FLIG HT
First sucessful rocket entered space in 1946.
2050
BEG IN MAR S COLINIZ ATION
SpaceX plans to send humans to mars and establish a colony.
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CHAPTER 2 HISTORY
1232
1591
Ancient Chinese Rocket
First Multi-Stage Rocket
The first true rocket is invented by the Chinese. Fire arrows are
German fireworks maker Johann Schmidlap invents the two-stage
used against the Mongol invaders.
rocket to reach higher altitudes. A large skyrocket (first stage) carries a smaller rocket (second stage).
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Ancient Rocketry Early Rocketry Modern Rocketry Future Plans
1687
1898
Newtons Third Law
Space Exploration Proposal
Sir Isaac Newton publishes his book Principia, which contains
After teaching Newthons laws to his students and testing what
his three laws of motion. Newtons third law states “for every
we call today “bottle rockets,” Russian schoolteacher Konstantin
action, there is an equal and opposite reaction.” This laid out
Tsiokovsky puts forward the idea of using rockets for space explo-
the scientific foundations for modern rocketry.
ration. He suggests liquid propellants would gain greater range.
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CHAPTER 2 HISTORY
1926
1946
Successful liquid-propellant rocket
First atmospheric testing
American Robert H Goddard flies a rocket powered by liquid
With the help of captured German rocket engineers, the United
oxygen and gasoline. Goddard goes on to build bigger rockets
States begins using V-2 rockets as sounding rockets to make
and higher rockets.
measurements of the atmosphere at high altitudes. Little was known of the atmosphere before this.
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Ancient Rocketry Early Rocketry Modern Rocketry Future Plans
1957
1958
First satellite – Sputnik 1
First American satellite launches
The Soviet Union launches the first Earth-orbiting artificial sat-
Jet Propulsion Laboratories launch Explorer 1, America’s first
ellite. This marks the first significant success of the space race
satellite. New Zealander Sir William Pickering is director of JPL.
between the world’s two superpowers.
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NASA Space Shuttle A view from NASA Space Shuttle looking down on Earth. The arm from the shuttle bay has been extended.
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CHAPTER 2 HISTORY
1958
1959
NASA Founded
First weather satellite launched
The United States formally organises its space programme and
The Vanguard 2 satellite is used by scientists to forecast the
calls it National Aeronautics and Space Administration.
weather. It was launched by the United States to be used for the military.
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Ancient Rocketry Early Rocketry Modern Rocketry Future Plans
1961
1969
First man to orbit Earth
Moon Landing
Russian scientist Yuri Gagarin becomes the first man to orbit Earth.
Apollo 11 is the first space flight to land people on the Moon.
Shortly after, American astronaut John Glenn orbits earth in a
Neil Armstrong is the first astronaut to set foot on the Moon. 12
capsule packed with so much equipment there is sitting room only.
astronauts walk on the Moon during 6 missions. Ed Cernan is the last man to step foot on the Moon in 1972.
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HOW ROCKETS WORK HISTORY
1981
2010
First Space Shuttle launch
SpaceX’s first Shuttle launch
NASA launches its first Space Shuttle. These are designed as
SpaceX, a private company working towards commercial space
reusable vehicles that would increase accessibility to orbit. Space
travel, launches Falcon 9. This unmanned capsule orbits the Earth
Shuttles have been used to place many satellites into orbit and
twice before landing in the Pacific Ocean.
to construct the International Space Station. The final space shuttle was launched in July 2011.
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Ancient Rocketry Early Rocketry Modern Rocketry Future Plans
2025
2030
Manned Mission to Asteroid
Manned Mission to Mars
President Obama’s plans to land humans on an Asteroid remain
Then years after NASA lands it’s 2020 rover, the agency hopes to
in effect. NASA hopes to enable austronaut missions to Asteroids
send humans to Mars. President Obama, in 2013, committed to
as early as 2021.
getting an astronaut to the Red Plant “in the 2030s.”
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CHAPTER 3 TYPICAL ROCKET PLAN
The Atlas Centaur One of the most successful space rockets ever developed is the Atlas, produced by the Lockheed Martin company. Atlas rockets have launched over 100 unmanned space missions, including voyages to the Moon, the Pioneer missions that flew past Jupiter and Venus, and the Voyager space probe that landed on Mars. NASA’s first Atlas rocket took off from Cape Canaveral, Florida, on June 11, 1957. The latest version, Atlas V, has been used from late 2001 as a launch vehicle for government and commercial satellites and is expected to remain in use until at least 2020.
One version of Atlas, known as the Atlas Centaur rocket, illustrates the basic idea of how a rocket works very well. It’s called the Atlas Centaur because the lower stage (a section of the rocket used for part of the flight) called Atlas is joined to an upper stage called Centaur. The rocket’s payload (cargo), typically a spacecraft or satellite, rides on top of the Centaur stage and is protected from heat and vibration by a nose cone called the payload fairing.
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CHAPTER 3 TYPICAL ROCKET PLAN
Satellite Launch Procedure The Atlas is one of the most basic Satellite launchers, it has a built in satellite inside the fairing cone that detaches at the appropriate alitutde.
Liftoff The Atlas stage powers the rocket with a two-chamber booster engine (operational during liftoff only), a sustainer engine (operational from liftoff until all fuel is exhausted), and four solid rocket boosters (SRBs). The Atlas stage contains 343,000 lbs (156,000 kg) of liquid fuel.
SRBs Jettisoned The solid rocket boosters are used to increase thrust during the first two minutes of the flight and jettisoned when their fuel supply is exhausted.
Booster Engine Jettisoned The booster engine cuts off and is jettisoned by releasing 10 pneumatic (air-operated) latches.
Payload Fairing Jettisoned Spring-operated thrusters jettison the protective payload faring once the rocket has cleared Earth’s atmosphere.
Atlas and Centaur Separate As the rocket near its orbit, the Atlas and Centaur stages separate and the Atlas stage is jettisoned.
Centaur Moves Into Orbit Centaur’s twin engines give it the precise altitude and velocity it needs to launch the satellite and ejects the satellite.
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1. RCM (Remote Control Module) Every un-manned satellite uses a RCM module which allows mission control back on Earth to remotely control when the rocket Separators and fairing cones detach as well as when the thrusters disengage.
2. Satellite The Satellite is released from the fairing cones and can propel itself in space.
3. Fairing Cone and Separators The fairing cone is an enclosure for transport. A rocket has multiple fairing cones that separate at multiple stages from launch to orbit and before descent. 4. Fuel Tanks Most heavy rockets contain two different types of fuel sources so all fuel tanks on the rocket may not contain the exact same type of fuel.
5. Solid Thrusters Solid thrusters are different from rocket engines, these thrusters are used to get past to the thickest of the atmosphere before being jettisoned.
6. Rocket Engine Rocket engines not only only excel the rocket forward, but some engines are turreted and can turn to shift to a certain angle to turn the rocket.
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CHAPTER 3 TYPICAL ROCKET PLAN
Burn Duration
0:06:54
Coast Duration Burn Duration
0:20:36
0:08:10
0. Orbit Achieved 3. Satellite Jettison Satellite Separates and engages thrusters to turn. t+ 0:04:54
t+ 0:40:04
2. Alignment Satellite aligns for orbit and engages thrusters. t+ 0:11:31
4. Fairing Cone Separates Fairing Cone that encloses the Satellite is separated before releaseing from the body. t+ 0:03:42
5. Solid Booster Jettison Solid boosters burn out and and detached from the body of the rocket. t+ 0:01:52
6. Centaur Atlas Launch Rocket blasts off Earth within 1 second of go for launch. t+ 1 sec
A Short Mission The time it takes to launch and achieve orbit is not very long. In fact it only takes a few minutes to reach space.
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CHAPTER 4 NASA SPACE SHUTTLE
The Rocket That Keeps Coming Back The Space Shuttle was a partially reusable low Earth orbital spacecraft system operated by the U.S. National Aeronautics and Space Administration (NASA), as part of the Space Shuttle program. Its official program name was Space Transportation System (STS), taken from a 1969 plan for a system of reusable spacecraft of which it was the only item funded for development. The first of four orbital test flights occurred in 1981, leading to operational flights beginning in 1982. They were used on a total of 135 missions from 1981 to 2011, launched from the Kennedy Space Center (KSC) in Florida. Operational missions launched numerous satellites, interplanetary probes, and the Hubble Space Telescope (HST); conducted science experiments in orbit; and participated in construction and servicing of the International Space Station. The Shuttle fleet’s total mission time was 1322 days, 19 hours, 21 minutes and 23 seconds.
Shuttle components included the Orbiter Vehicle (OV), a pair of recoverable solid rocket boosters (SRBs), and the expendable external tank (ET) containing liquid hydrogen and liquid oxygen. The Shuttle was launched vertically, like a conventional rocket, with the two SRBs operating in parallel with the OV’s three main engines, which were fueled from the ET. The SRBs were jettisoned before the vehicle reached orbit, and the ET was jettisoned just before orbit insertion, which used the orbiter’s two Orbital Maneuvering System (OMS) engines. At the conclusion of the mission, the orbiter fired its OMS to deorbit and re-enter the atmosphere. The orbiter then glided as a spaceplane to a runway landing, usually at the Shuttle Landing Facility of KSC or Rogers Dry Lake in Edwards Air Force Base, California. After landing at Edwards, the orbiter was flown back to the KSC on the Shuttle Carrier Aircraft, a specially modified Boeing 747.
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CHAPTER 4 NASA SPACE SHUTTLE
How did the Shuttle work? The main component of the Shuttle was a spacecraft about two thirds the size of a 747 airplane (“Jumbo Jet”) called the orbiter. This was launched by two solid rocket boosters (SRBs) fixed to its underside, which burned solid fuel inside them. In between the SRBs, a giant external tank (ET) fed around 528,000 gallons (2 million liters) of liquid fuel to the orbiter’s three engines. This vast amount of fuel was needed to accelerate the Shuttle to a speed of roughly 17,500 mph (28,000 km/h) to reach an orbit of 190–330 miles (304–528 km) above Earth. During liftoff, the Shuttle’s main engines burned fuel so quickly that they could drain a family-sizedswimming pool in just 25 seconds! Each orbiter cost roughly $2 billion to build and each Shuttle mission cost roughly $450 million.
Life in the Shuttle Each Space Shuttle mission lasted up to two weeks, so the orbiter needed a comfortable-but-compact, two-story living area. On the top level were the pilot’s seats and cockpit controls. A ladder led down to a large sleeping area, galley kitchen, storage lockers, gym, and a vacuum toilet that worked even in space. The astronauts ate their food with metal knives and forks held to metal trays with magnets; this stopped them floating away in the Shuttle’s near-zero gravity.
Shuttle missions Space Shuttle missions often made headline news around the world. The maiden voyage on April 12, 1981, confirmed the Shuttle could successfully return from space. Another notable flight in April 1984 involved astronauts repairing a crippled satellite in the Shuttle’s cargo bay before returning it successfully to space. Two years later, the orbiter Challenger exploded shortly after takeoff killing all seven crew members. Flights resumed in late 1988 and the Hubble Space Telescope was launched in 1990. Disaster struck again in February 2003, when the Space Shuttle Columbia was destroyed as it returned to Earth. The final Shuttle voyage launched on July 8, 2011, after which the four remaining orbiters were retired to science and aviation museums spread across the United States.
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Shuttle Cockpit The space shuttle cockpit contains two pilot seats, in case of an emergenc, the co-pilot can take command of the space shuttle.
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In Orbit The NASA spaceshuttle orbits Earth’s beautiful atmosphere.
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CHAPTER 4 NASA SPACE SHUTTLE
From takeoff to landing During a typical one-week voyage, the Shuttle launched from its base at Kennedy Space Center (KSC), Florida, and carried out its mission several hundred miles above Earth’s surface. When the mission was complete, it returned to Earth’s atmosphere and made an unpowered landing, like a glider, either at KSC or at Edwards Air Force Base in California. At 15,000 ft (4572 m) long, the Edwards landing strip is roughly twice the length of a typical airport runway.
Reentry The Shuttle’s unique feature was its ability to venture into space and return to Earth intact. The main problem with this, however, was that friction would heat up the orbiter to nearly 1927°C (3500°F) as it passed into Earth’s atmosphere, so it was coated with about 20,000 heat-resistant ceramic “tiles” (refractory bricks) to stop it burning up on reentry. A tough material called reinforced carbon-carbon was used in the tiles on the wing edges, the nose, and other areas where temperatures could exceed 1260°C (2300°F). Black high-purity silica tiles 1–5 inches (2.5–12.7 cm) thick were individually cemented to the underside of the orbiter to protect it from temperatures of 649–1260°C (1200–2300°F). Less heat reached the upper surface of the craft, so it was protected either by white tiles or by a blanket made from a silica composite.
Inside the Shuttle cargo bay At 60 ft (18.3 m) long and 15 ft (4.6 m) wide, the orbiter’s cargo bay was big enough to hold a a satellite or a couple of trucks parked side by side. It contained a variety of sensors and scientific instruments and a 50 ft (15 m) grabber arm, used for launching and retrieving satellites. The reflective inside doors of the cargo bay doubled up as heat shields to protect the cargo from solar radiation. The Shuttle could not launch a satellite directly into geostationary orbit (a fixed orbit over a certain place on Earth). Instead, it spun the satellite slowly out of the cargo bay. When the satellite was clear, its own rocket motors would fire and power it into position.
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Satellite Lanch NASA’s Discovery with it’s cargo bay open and launching a satellite. With the shuttle in orbit, the satellite can be released and will continue to stay in orbit even when the shuttle lands on earth.
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Docked at ISS The Endeavour Space Shuttle docked at the International Space Station.
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CHAPTER 5 ORBITER STRUCTURE
Pressurized Crew Module The orbiter’s two-level crew cabin provides 2,325 cubic feet (65.8 cubic meters) of living and working space. Controls on the flight deck allow the ship to be manually piloted from either the left or right seat. In an emergency the orbiter can be returned to Earth by one crew member. Another panel opposite of the flight controls are used for navigation, communication, docking and it also includes the controls for the extendable arm. The cabin is enclosed in case of an emergency, it can sustain life independently until the shuttle can reach Earth.
The crew module is protected by Thermal Protection System materials on both the inside and the outside as well as the outside of the cargo bay. The Thermal Protection System works as multi-purpose shield to both the cold and the heat. It protects the crew and equipment from freezing in outer space at degrees of -121 °C, approximately −186 °F. It also protects the shuttle upon re-entry in which the shuttle ripts through the atmosphere creating so much friction it acts like a match. The shuttles outside temperature reaches 1,649 °C which equates to about 3,000 °F. The cabin requires double the coating as it it keeps the interior insulated for keeping the crew arm and in case of an emergency, it prevents the crew from freezing in space and prevents them from burning upon re-entry into the Earths atmosphere.
In addition to crew protection from the heat and cold by the ship, the crew is also required to utilize the Advanced Crew Escape Suites which are sometimes called “Pumpkin Suites” due to their color. This suite was a full pressure suit that began to be worn by Space Shuttle crews after STS-65, for the ascent and entry portions of flight. The suite consists of two different pieces, a the one-piece pressure garment assembly with integrated pressure bladders and ventilation system. Oxygen is fed through a connector at the wearer’s left thigh and is transmitted to the helmet, via a special connector at the base of the neckring. The neckring attaches to the second piece which is a full pressure helmet with a locking clear visor and a black sunshade worn to reduce any glare from reflected sunlight, especially during the approach and landing phases of the mission.
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RCS Module The Reaction Control System is responsible for manuvering the shuttle in space.
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CHAPTER 5 ORBITER STRUCTURE
Attitude Control System The Space Shuttle orbiter resembled an airplane in its design, with a standard-looking fuselage and two double delta wings, both swept wings at an angle of 81 degrees at their inner leading edges and 45 degrees at their outer leading edges. The vertical stabilizer of the orbiter had a leading edge that was swept back at a 45-degree angle. There were four elevons mounted at the trailing edges of the delta wings, and the combination rudder and speed brake was attached at the trailing edge of the vertical stabilizer. These, along with a movable body flap located underneath the main engines, controlled the orbiter during later stages of descent through the atmosphere and landing. The Reaction Control System (RCS) was composed of 44 small liquid-fueled rocket thrusters and their very sophisticated computerized (fly-by-wire) flight control system, which utilized computationally intensive digital Kalman filtering. This control system carried out the usual attitude control along the pitch, roll, and yaw axes during all of the flight phases of launching, orbiting, and re-entry. This system also executed any needed orbital maneuvers, including all changes in the orbit’s altitude, orbital plane, and eccentricity. These were all operations that required a lot more power and energy than mere attitude control. The forward rockets of the Reaction Control System, located near the nose of the Space Shuttle orbiter, included 14 primary and two vernier RCS rockets. The aft RCS engines were located in the two Orbital Maneuvering System (OMS) pods at the rear of the orbiter, and these included 12 primary (PRCS) and two vernier (VRCS) engines in each pod. The PRCS system provided the pointing control of the Orbiter, and the VRCS was used for fine maneuvering during the rendezvous, docking, and undocking maneuvers with the International Space Station, or formerly with the Russian Mir space station. The RCS also controlled the attitude of the orbiter during most of its re-entry into the Earth’s atmosphere – until the air became dense enough that the rudder, elevons and body flap became effective.
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CHAPTER 5 ORBITER STRUCTURE
Propulsion Three Space Shuttle Main Engines (SSMEs) were mounted on the orbiter’s aft fuselage in the pattern of an equilateral triangle. These three liquidfueled engines could be swiveled 10.5 degrees vertically and 8.5 degrees horizontally during the rocket-powered ascent of the orbiter in order to change the direction of their thrust. Hence, they steered the entire Space Shuttle, as well as providing rocket thrust towards orbit. The aft fuselage also housed three auxiliary power units (APU). The APUs chemically converted hydrazine fuel from a liquid state to a gas state, powering a hydraulic pump which supplied pressure for all of the hydraulic system, including the hydraulic sub-system that pointed the three main liquid-fueled rocket engines, under computerized flight control. The hydraulic pressure generated was also used to control all of the orbiter’s “flight control surfaces” (the elevons, rudder, speed brake, etc.), to deploy the landing gear of the orbiter, and to retract the umbilical hose connection doors located near the rear landing gear, which supplied the orbiter’s SSMEs with liquid hydrogen and oxygen from the external tank. Two Orbital Maneuvering System (OMS) thrusters were mounted in two separate removable pods on the orbiter’s aft fuselage, located between the SSMEs and the vertical stabilizer. The OMS engines provided significant thrust for coarse orbital maneuvers, including insertion, circularization, transfer, rendezvous, deorbit, abort to orbit, and to abort once around. At lift-off, two solid rocket boosters (SRBs) were used to take the vehicle to an altitude of roughly 140,000 feet.
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CHAPTER 5 ORBITER STRUCTURE
154 ft.
170 ft.
Standing Tall
6ft
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The launch vehicle stands out like a skyscraper before launch. It is in fact almost 30 times bigger than the average human. The shuttle engine alone stands 12 feet tall and that doesn’t include the fuel inline.
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CHAPTER 6 BLASTOFF
From Earth to Space The journey of a typical Space Shuttle is not a very long one. The average time it takes for a shuttle to reach from T-Minus Zero (the second the shuttle launches) is about 8.5 minutes. For launch, rockets go through multiple stages. These stages vary by the number of things happening on a rocket, which involved number of tanks, number of separators, and the size of the rocket. The rocket drops fuel tanks as it accelerates into space to get rid of dead weight. Although modern rockets have mulitple stages, there are 6 main stages in the space shuttle and these stages are always counted down instead of up.
Stage 5 - T-Minus Zero The fifty stage, stage 5, is the Liftoff stage. It involves the rocket using it’s solid rocket boosters and it’s main shuttle engines to generate 7.3 million pounds (32.4 million newtons) of thrust to lift the shuttle off it’s launch platform and accelerate towards space.
Stage 4 - Booster Separation The fourth stage, stage 4, is the stage where the two solid fuel boosters run out of fuel and jettisoned from the main liquid fuel tank and fall back down to Earth. Jettisoned boosters land and float in the ocean where the recovery team is standing by to return the empty booster back to the shuttle headquarters.
Stage 3 - Engine Shutdown The third stage, stage 3, is focused on keeping the engine alive. Stage 3 requires shutting down the engine just before the main external liquid fuel tank is emptied to avoid the engine from taking damage. Burning the fuel tank dry would destroy the engine and render the shuttle’s propulsion system useless.
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Stage 2 - Tank Jettison The second stage of the journey of the rocket into space consists of ejecting the external liquid fuel tank once it is nearly depleted. The tank then gravitates towards Earth and lands further into the ocean to where it is then recovered for repair and reuse.
Stage 1 - Engine Activated The first stage, Stage 1, follows the jettison of the fuel tank to leave the immediate area of the fuel tank and accelerate further before manuvering to shift into orbit.
Stage 0 - Orbit The final stage is the last part of the assent mission which involves the moving into orbit. Once this stage has been completed, the shuttle can remain in orbit around the Earth until the next mission to either desend back to earth or to alter it’s orbit.
In Orbit Once the shuttle has reached orbit, it is typically used for research purposes. It isn’t just a mode of transport: It’s a laboratory, too. There have been 22 Spacelab missions, or missions where science, astronomy, and physics have been studied inside a special module carried on the space shuttle. Spacelab, a reusable laboratory built for use on space shuttle flights, allowed scientists to perform experiments in microgravity . Starting in 1983’s Challenger missions, animals became a prime component of space science. On the STS-7 mission, the social activities of ant colonies in zero gravity were examined, and during STS-8, six rats were flown in the Animal Enclosure module to study animal behavior in space.
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CHAPTER 7 DESCENT
From Orbit to Earth When it is time to return to Earth, the orbiter is rotated tail-first into the direction of travel to prepare for another firing of the orbital maneuvering system engines. This firing is called the deorbit burn. Time of ignition (TIG) is usually about an hour before landing. The burn lasts three to four minutes and slows the shuttle enough to begin its descent.
TIG-4 hours Crew members begin preparations for landing. The orbiter’s onboard computers are configured for entry, as is the hydraulic system that powers the orbiter’s aerosurfaces; its rudder speed brake and wing elevons.
TIG-3 hours The payload bay doors are closed. Mission Control gives the commander the “go” for Ops 3, the portion of the orbiter’s flight control software that manages entry and landing.
TIG-2 hours Starting with the commander and pilot, the flight crew members don their orange launch and entry suits and strap into their seats.
TIG-1 hour Mission Control gives the “go” for deorbit burn.
Deorbit Burn The orbiter and crew are officially on their way home. During reentry and landing, the orbiter is not powered by engines. Instead, it flies like a hightech glider, relying first on its steering jets and then its aerosurfaces to control the airflow around it.
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Landing-30 minutes Roughly half an hour after the deorbit burn, the orbiter will begin to encounter the effects of the atmosphere. Called entry interface, this point usually takes place at an altitude of about 80 miles, and more than 5,000 statute miles from the landing site. Early in reentry, the orbiter’s orientation is controlled by the aft steering jets, part of the reaction control system. But during descent, the vehicle flies less like a spacecraft and more like an aircraft. Its aerosurfaces gradually become active as air pressure builds. As those surfaces become usable, the steering jets turn off automatically. As the orbiter slices through the atmosphere faster than the speed of sound, the sonic boom; really, two distinct claps less than a second apart which can be heard across parts of Florida, depending on the flight path.
Landing-5 minutes The orbiter’s velocity eases below the speed of sound about 25 statute miles from the runway. As the orbiter nears the Shuttle Landing Facility, the commander takes manual control, piloting the vehicle to touchdown on one of two ends of the SLF. As it aligns with the runway, the orbiter begins a steep descent with the nose angled as much as 19 degrees down from horizontal. This glide slope is seven times steeper than the average commercial airliner landing. During the final approach, the vehicle drops toward the runway 20 times faster than a commercial airliner as its rate of descent and airspeed increase. At less than 2,000 feet above the ground, the commander raises the nose and slows the rate of descent in preparation for touchdown.
Touchdown The main and nose landing gear are deployed and locked in place. The orbiter’s main landing gear touches down on the runway at 214 to 226 miles per hour, followed by the nose gear. The drag chute is deployed, and the orbiter coasts to a stop.
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