SpaceX 6

Starship and Super Heavy Booster

Jim Rauf

OLLI Fall 2023 1

1 Introduction: topics , some basics and rocket pioneers
2 SpaceX founding , Musk’s vision, facilities, organization, personnel
3 SpaceX and NASA commercial funding
4 Falcon rockets and engines , Falcon 1, Falcon 9 and Falcon Heavy
5 Dragon spacecraft , Cargo Dragon and Crew Dragon
6 Super Heavy booster and engines and Starship Spacecraft
7 Starship Artemis Moon Human Landing System and Starlink
8 Musk’s Mars vision , plans , challenges and SpaceX summary

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• 2002 SpaceX founded
• 2008 Falcon 1 launch to LEO
• 2010 First Falcon 9 launch
• 2012 First Cargo Dragon flight to ISS
• 2014 Falcon 9 first stage was recovered
• 2018 First Falcon Heavy launch
• 2019 All three Falcon Heavy stages land
• 2020 First Crew dragon flight to ISS
• SpaceX launches to date
• Falcon 9s 266
• Falcon Heavy 8
• SpaceX’s next rocket is the Super Heavy and
Starship

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 Starship System

• 2012 preliminary Super Heavy and Starship ,

previously known as the Interplanetary
Transport System (ITS) and the Big Falcon
Rocket (BFR) design work began
• 2019, SpaceX began to refer to the Starship /
Super Heavy combination as the Starship
System
• Starship system’s ultimate mission: to ferry up
to 100 peoples to Mars on each flight!
• The vehicle is a fully reuseable system:
• Super Heavy first stage
• Starship spacecraft second stage
• First flight of a Starship Test Article ,
Starhopper, was July 25,2019
• Test articles and prototypes of Starship and
Super Heavy continue to the present time

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 Starship System

• Both stages are made of 301 stainless steel alloy

• Composition: Fe, <0.15%C, 16-18%Cr, 6-8%Ni,
<2%Mn, <1%Si, <0.045%P, <0.03%S
• 301 Stainless Steel is about 67 times cheaper than
carbon composites and easier to work with and is more
tolerant of high temperatures
• Temperature limit for carbon composites ~400 F
• Both stages use the SpaceX designed Raptor engines
which use cryogenic Liquid Oxygen LOX and Liquid
Methane (CH4)
• Super Heavy (first stage) has 33 engines generating ~16.7
million + pounds of thrust
• Starship (second stage) has 6 engines (3 sea level engines
and 3 vacuum) generating ~3.3 million + pounds of thrust

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 Starship System Super Heavy

• The Super Heavy booster is~233 ft tall and ~30 ft in

diameter
• It has thirty-three Raptor engines arranged in concentric
rings
• The outer ring of 20 engines have their gimbal
actuators removed to save weight and a modified
injector with reduced throttle performance in exchange
for greater thrust
• Maximum thrust (33 engines) is 17,100,000 lbf
• The booster's tanks can hold 7,900,000 lb of propellant
• Liquid oxygen (LOX) ~6,200,000 lb
• Liquid methane (CH4) ~1,800,000 lb
• The final design will have a dry mass between
~ 350,000 lb and ~440,000 lb
• The tanks weighing ~180,000 lb
• The interstage weighing ~44,000 lb

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 Starship System Super Heavy

• The booster is equipped with four electrically

actuated grid fins ~ 6,600 lb each
• Adjacent pairs of grid fins are spaced sixty degrees apart
• The grid fins do not retract and remain extended during
ascent
• The booster has can be lifted through
protruding hardpoints located between grid fins
• The vented interstage is between the booster and the
Starship
• This enables Starship to use hot staging
• The second stage separates when some of the first stages
engine are still firing – allowing increased pay load
• During unpowered flight in the vacuum of space, control
authority is provided by cold gas thrusters fed with
residual ullage gas

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 Starship System Super Heavy Mission

• About one hour and thirty-nine minutes before flight, the

super heavy booster begins propellant load
• At the T- 16:40 mark, engine chill begins on the booster.
This is to protect the engine's turbopumps from thermal
shock
• At eight seconds before launch, the thirty-three engines
startup-sequence begins
• After liftoff, the engines burn for 169 seconds
• 30 of its engines shut off, leaving the three center ones
running at 50% thrust
• The Starship ignites its engines while still attached to the
booster and separates
• The boostback burn lasts for 55 seconds
• About eight minutes into the flight, the engines reignite,
and the booster is caught by a pair of mechanical arms.

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 Starship System Starship Spacecraft

• The Starship spacecraft is ~ 160 ft tall, and ~30 ft in

diameter
• It has a has six Raptor engines – three “vacuum” engines
• Future vehicles may have an additional 3 Raptor Vacuum
engines for increased payload capacity
• The vehicle's payload bay, is ~ 56 ft tall by ~ 26 ft in
diameter providing a volume of ~35,000 cu ft
• A larger ~ 72 ft tall payload bay can handle larger
payloads
• Starship has a total propellant capacity of
~2,600,000 lb across its main tanks and header tanks
• The header tanks are better insulated due to their
position and are reserved for use to flip and land the
spacecraft following reentry
• A set of reaction control thrusters, which use the
pressure in the fuel tank, control attitude while in space
Ship 25 atop the Booster 9 at Starbase on Sept. 5, 2023

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 Starship System Starship Spacecraft

• The spacecraft has four body flaps, two forward flaps and
two aft flaps , to control the spacecraft's orientation and
help dissipate energy during atmospheric entry
• According to SpaceX, the flaps replace the need for wings
or tailplane, reduce the fuel needed for landing, and
allow landing at destinations in the Solar System where
runways don't exist (Mars ?)
• Under the forward flaps, hardpoints are used for lifting
and catching the spacecraft via mechanical arms
• The flap's hinges are sealed in aero-covers because they
would be easily damaged during reentry

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 Starship System Starship Spacecraft

• Starship's heat shield, composed of thousands of

hexagonal black tiles that can withstand temperatures of
2,600 °F, is designed to be used many times without
maintenance between flights
• The tiles are made of silica and are attached with pins
rather than glued with small gaps in between to allow
for thermal expansion
• Tiles hexagonal shape facilitate mass production and
prevent hot plasma from causing severe damage to the
vehicle

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 Starship System Starship Spacecraft Variants
• For satellite launch, Starship will have a large cargo
door that will open to release payloads and close upon
reentry
• Instead of a cleanroom, payloads are integrated directly
into Starship's payload bay, which requires purging the
payload bay with temperature-controlled clean air
• To deploy Starlink satellites, the cargo door will be
replaced with a slot and dispenser rack
• Crewed Starship vehicles would replace the cargo bay
with a pressurized crew section and have a life support
system
• For long-duration missions, such as crewed flights to
Mars, SpaceX describes the interior as potentially
including "private cabins, large communal areas,
centralized storage, solar storm shelters, and a viewing
gallery
• Artemis Program Human Landing system (HLS) will
have a NASA docking system, solar panels and retro
propulsion system and some other features to support
the Moon landing

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 Starbase Boca Chica , TX

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 Starbase Boca Chica, TX

• Starship and Super Heavy development and

testing is conducted at SpaceX’s “Starbase” in
Boca Chica, TX
• The site feature a launch and landing pad and a
146-meter-tall launch tower
• It is designed to catch the returning boosters
by closing a pair of arms around the booster
• Work at the Starbase has resulted in protests
from local residents – noise

Bing Videos

https://www.spacex.com/vehicles/starship/

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 Raptor Engine
• The Raptor is a cryogenic liquid methane and liquid • The methane fuel is cryogenic – meaning it is cooled to a
oxygen powered engine developed by SpaceX liquid state
• It is the first full-flow staged combustion cycle engine to • This increases the density of the methane and allows
have flown. more of it to be carried by the rocket.
• Why the Raptor engine uses liquid methane and oxygen • The Raptor’s oxidizer, oxygen, is also cryogenic
propellant
• While rocket engines could theoretically use other
• Rocket engines provide thrust by forcing a fuel to react substances as an oxidizer, liquid oxygen is the only one
with an oxidizer. The reaction between these propellants that has ever been used
is what you call combustion.
• Methane is an unusual choice for rocket fuel
• Traditionally, RP-1 (a refined form of kerosene) or
hydrogen are the fuels used for launch vehicles
• SpaceX chose methane as the Raptor’s fuel for one main
reason – their ambition to go to Mars
• Methane will be relatively easy to make and keep in the
liquid state on Mars

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 Raptor Engine
• The full-flow staged combustion cycle • The Raptor uses regenerative cooling
• While other full-flow staged combustion cycle engines • This involves sending the cryogenic methane around the
have been lab tested in the past, the Raptor is the first to outside of the main combustion chamber to keep it cool
have flown
• The warmed liquid methane then flows to the pre-burner
• This type of combustion cycle is particularly complex to continue the cycle
• ‘Staged combustion’ refers to some of the combustion • Reusability has been a big consideration in the Raptor’s
occurring in pre-burners before the main combustion design
chamber
• SpaceX aims to reuse each engine 1000 times
• These pre-burners drive turbines, which in-turn drive
turbopumps • As most other rocket engines have had little to no
reusability, the cost per flight of the Raptor will be
• The turbopumps provide propellant flow to the engine comparatively low
• ‘Full-flow’ refers to all of the propellant passing through a • This will make space travel more economical and
pre-burner accessible in the future
• One pre-burner drives a turbopump for the liquid
methane and produces methane-rich gas
• The other pre-burner drives a turbopump for the liquid
oxygen and produces oxygen rich gas
• These gases then combust together in the main chamber
and provide thrust
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 Raptor Engine
• The Raptor is a cryogenic liquid methane and liquid • The methane fuel is cryogenic – meaning it is cooled to a
oxygen powered engine developed by SpaceX liquid state
• It is the first full-flow staged combustion cycle engine to • This increases the density of the methane and allows
have flown. more of it to be carried by the rocket.
• Why the Raptor engine uses liquid methane and oxygen • The Raptor’s oxidizer, oxygen, is also cryogenic
propellant
Propellant Boiling Temp Density Energy/liter
• Rocket engines provide thrust by forcing a fuel to react
CH4 -259 F (-162 C) 0.46 kg/l 22.0 Mj/l
with an oxidizer. The reaction between these propellants
O2 -297 F (-183 C) 1.14 kg/l ----
is what you call combustion. H2 -423 F (-253 C) 0.07 kg/l 10.0 Mj/l
• Methane is an unusual choice for rocket fuel
Specific Impulse generated by modern examples of
• Traditionally, RP-1 (a refined form of kerosene) or rocket engines (liquid oxygen oxidizer) running on
hydrogen are the fuels used for launch vehicles each fuel type:
• SpaceX chose methane as the Raptor’s fuel for one main 1. Liquid Hydrogen: 366 – 452 seconds (Space
reason – their ambition to go to Mars Shuttle/SLS RS-25 engine)
• Unlike RP-1 and hydrogen, methane will be relatively easy 2. Liquid Methane: 330 – 350 seconds (SpaceX
to make and keep in the liquid state on Mars Raptor engine)
• This makes missions to Mars possible without the need to 3. RP-1 Propellant: 282 – 311 seconds (SpaceX
bring extra fuel for the return trip Merlin engine)

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 Raptor Engine The Full-flow Staged Combustion Cycle
• ‘Staged combustion’ refers to some of the combustion
occurring in pre-burners before the main combustion
chamber
• The pre-burners drive turbines, which drive turbopumps
• The turbopumps provide propellant flow to the engine
• ‘Full-flow’ refers to all of the propellant passing through a
pre-burner
• One pre-burner produces methane-rich gas and drives a
turbopump for the liquid methane
• The other pre-burner produces oxygen-rich gas and
drives a turbopump for liquid oxygen
• The two gases combust together in the main chamber
and provide thrust

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 Raptor Engine The Full-flow Staged Combustion Cycle
• The Raptor uses regenerative cooling
• This involves sending the cryogenic methane around the
outside of the main combustion chamber to keep it cool
• The warmed liquid methane then flows to the pre-burner
to continue the cycle
• Reusability has been a big consideration in the Raptor’s
design
• SpaceX aims to reuse each engine 1000 times

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 Raptor Engine The Full-flow Staged Combustion Cycle
• Raptor engines are optimized for atmospheric operation
and vacuum operation
• The vacuum optimized engines have larger exhaust exit
areas to expand the exhaust gas int the vacuum of space
• SpaceX continues to develop the Raptor engines
• Raptor 1 engines thrust
• 410,000 lb

• Raptor 2 engines thrust/pressure/Temperature:

• 510,000 lb sea level /4,400psi/~6,500 F
• 570,000 lb vacuum

• Raptor 3 engines:
• 590,000 lb sea level/5,100 psi/~6,500 F

• Both the Super Heavy and the Starship have both sea
level and vacuum engine

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Raptor Engine

Engines optimized for vacuum

operation have larger nozzle
exit areas than those optimized
for sea level or atmospheric
operation

Raptor A/A*
Sea Level ~40
Vacuum ~200

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Raptor Engine Testing

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SpaceX Raptor Engine
Sea Level Vacuum

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 Super Heavy Booster and Starship Construction
• The stainless steel rings that make up the Starship
system’s structure are welded together using laser
welding or TIP-TIG welding
• Friction-stir welding is used on the aluminum
material in the Falcon 9
• Shapes of SS nose one panels has changed on recent
prototypes as have configuration of SS rings
• The grid fins do not retract and remain extended during
ascent
• During unpowered flight in the vacuum of space, control
authority is provided by cold gas thrusters fed with
residual ullage gas
• Space between the top of the propellant load and the top of the tank
is known as "ullage space"

• The interstage also has protruding hardpoints, located

between grid fins, allowing the booster to be lifted or
caught by the launch tower
• All boosters now have an additional 2m tall vented
interstage added, as well as a protective dome
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Evolution of Starship System

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 Integrated Flight Test

April 20, 2023, SpaceX launched the first Integrated Flight Test
of its Starship rocket
The prototype vehicle was destroyed less than four minutes
after lifting off from the SpaceX Starbase in Boca Chica, Texas.

https://www.youtube.com/watch?v=bl7IqyEyqhY

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 Next Integrated Flight Test

Starship 25 SpaceX:
Test is ready to go
Awaiting OK from FAA

Booster 9
Booster 9

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1 Introduction: topics , some basics and rocket pioneers
2 SpaceX founding , Musk’s vision, facilities, organization, personnel
3 SpaceX and NASA commercial funding
4 Falcon rockets and engines , Falcon 1, Falcon 9 and Falcon Heavy
5 Dragon spacecraft , Cargo Dragon and Crew Dragon
6 Super Heavy booster and engines and Starship Spacecraft
7 Starship Artemis Moon Human Landing System and Starlink
8 Musk’s Mars vision , plans , challenges and SpaceX summary

OLLI Fall 2023 28