SpaceX Starship Is Bigger and Cheaper Than the External Shuttle Tank

The SpaceX Starship will have six Raptor engines but will still be larger and cheaper than the external fuel tanks of the Space Shuttle.

Elon Musk has a goal of building Starships for $5 million. Elon Musk has indicated that one of the reasons for switching to stainless steel for the SpaceX Super Heavy Starship was to use $3 per kilogram of steel instead of $200 per kilogram for carbon composite. SpaceX will save $10-24 million on cost of materials. If the Raptor and Merlin engines had similar cost then each Starship upper stage should be about half of the cost of a Falcon 9. A Falcon 9 combined upper and lower stage) costs about $30-40 million to build. This would mean that each Starship should currently cost about $15-20 million to build.

A lightweight external space shuttle fuel tank, ET 94, was built at a cost of $75 million. This would be about $140 million in todays dollars after adjusting for inflation. The lightweight tank was intended to pull the shuttle into low-earth orbit. This version was cheaper to build than the super lightweight tanks, which were able to carry more cargo to the International Space Station.

If SpaceX only achieves part of the cost savings that Elon Musk is targeting and reaches a $14 million cost then they would be ten times cheaper than a Shuttle fuel tank. If the $5 million cost is reached then the SpaceX Starship will be nearly 30 times cheaper than a Shuttle external fuel tank.

The lightweight fuel tank weighs 66,000 pounds. The Standard weight fuel tank weighed about 77,000-80,000 pounds.

The Space shuttle external fuel tank specifications were:
Height 46.9 meter (153.8 ft)
Diameter 8.4 meters (27.6 ft)

The SpaceX Starship upper stage dimensions:
Height 160-foot-tall (50 meters),
Diameter 30-foot (9 meter)

It will be fully reusable spacecraft with a dry mass of 260,000 lb (120 tons) or less. It will be powered by six methane/oxygen-propellant Raptor engines.
Total Starship thrust will be approximately 2,600,000 lbf (11,500 kN).

There will be several versions of Starship:
* Spaceship: a large, long-duration spacecraft capable of carrying passengers or cargo to interplanetary destinations, to LEO, or Earth-to-Earth spaceflight.

* Satellite delivery spacecraft: a vehicle able to transport and place spacecraft into orbit, or handle the in-space recovery of spacecraft and space debris for return to Earth or movement to another orbit. This will have a large cargo bay door that can open in space to facilitate delivery and pickup of cargo.

* Tanker: a cargo-only propellant tanker to support the refilling of propellants in Earth orbit. The tanker will enable launching a heavy spacecraft to interplanetary space as the spacecraft being refueled can use its tanks twice, first to reach LEO and afterwards to leave Earth orbit. The tanker variant, also required for high-payload lunar flights, is expected to come only later; initial in-space propellant transfer will be from one standard Starship to another.

* Lunar-surface-to-orbit transport: A variant of Starship without airbrakes or heat shielding that is required for in-atmosphere-operations. It will have a docking port on the nose and have white paint (as opposed to the bare steel planned for regular Starships). On 30 April 2020, NASA selected SpaceX to develop a human-rated lunar lander for the Artemis program, therefore requiring SpaceX to develop an approach for a direct lunar landing.

SOURCES- SpaceX, NASA, Wikipedia, LA Times
Written By Brian Wang,

16 thoughts on “SpaceX Starship Is Bigger and Cheaper Than the External Shuttle Tank”

  1. To continue, 2 shorty Starships could form a heavy lift lunar lander. 
    Two shortys adapted as lunar landers might be connected by a framework that joins their upper 10m or so and holds them parallel and say 30m apart. The cargo would be carried on the framework and lowered to the ground after landing. This combination would have available the thrust of 2 starships and should be able handle ANY likely cargo.
    With so much thrust, it may need to act as a skycrane, lowering it’s cargo to the surface, to avoid erosion of the landing site and then return to orbit to refuel. 
    Anything that might be a payload from earth would be landable on the moon. Items built at a moon base could be relocated on the moon or lifted to orbit. Attach a habitable nose cone to one end and it is now a manned vessel at minimal cost.
    Of course, several could be mounted to a frame work and then one might move asteroids and boost Starships to the outer planets.

  2. I suggest a ‘shorty’ Starship.
    It would be the standard vehicle up to the top of the propellent tanks, terminating in a universal ( 9m ) docking ring. Everything forward of this is payload and can be whatever is desired, as long as it is aerodynamic enough to be flown. The Shorty would be able to re-enter the atmosphere and land. It would always return in a minimal configuration so would need no forward wings and smaller rear wings. Likely fewer landing legs too.
    At a guess this would remove some 30 tons from the vehicle that would now be part of the payload.
    An example:
    The two launch 50m diameter space station. 
    If ‘payload’ is limited to say 30m x 12m, then launch 1 provides the hub and spokes. The nose cone is made habitable and sits on top of 7 x 4m diam 20m long m tubular sections arranged in a hexagon with a core. The core is permanently attached to the base of the nose cone and the outer 6 sections form 6 spokes when attatched to the lower sides of the cone. To make it aerodynamic enough to fly, the gaps in between the outer sections are faired over with suitably reinforced solar arrays that will power the station. 
    Launch 2 is another 6 sections under a nose cone. The outer sections form the ring and the center void is filled with a stack of connector blocks to join the rings to the spokes. 
    Voila, a 50 m diameter station in 2 launches.
    A shorty could be fueled and docked to the original connector ring giving a large spaceship with artificial gravity.

  3. Agreed. In the medium term time line, there aren’t many things other than military that will inject funding and ramp up space infrastructure quickly enough to satisfy our childhood dreams of space exploration. We are not getting any younger.

  4. And I think that that is good. Perhaps this can give the USA an edge against China. Let us hope that China will be 10 years behind the USA in terms of military technology from now until the end of time.

  5. And the weaponized US SpaceForce variant BattleStar-ship.
    Equipped with powerful lasers to illuminate distant objects for various purposes.

  6. In my humble opinion, I think that taking into account that the new larger fairing FH has more than 250 m3 of internal volume (4.6 meter diameter and 16.5 meter high), four (or more) stations with this shape can be attached to a hub by the upper part to be rotated, at may be the martian gravity in the middle of its high, and can be launched almost finished from ground. This is the ISS internal volume with gravity using and re-using only 4 FH and 1 F9 launches.

  7. They wouldn’t need the Superheavy or for that matter the launch infrastructure, just the Starship. People with private jets don’t need their own airports. People with large yachts rarely sail them across the ocean, they load them on a cargo ship for that and only actually sail them at the destination.

    $50-$100M would fit with the cost of yachts and jets so there would be private luxury Starship sales if SpaceX wanted. The same Starship could fly hypersonic point to point, or to orbit to meet SpaceStation or for orbital cruises or take on propellant for other trips.

  8. The existence of the luxury yacht kind of depends on the existence of a range of luxury islands and ports that you can visit in said yacht.
    Before the development of such locations you can have private individuals with their own personal exploration craft, but they tend towards the practical and tough rather than luxurious.
    So yes, private luxury spaceships, but only after there are space hotels to visit.

  9. Nevertheless in its time the space shuttle was a great technological achievement, currently we don’t have space planes. And i’d be more surprised if the space shuttle were cheaper, as a lot has improved since then. From computers, to manufacturing, to material science.

  10. I believe they will be the first, and probably only competitor to make it to the Moon around the estimated dates…

    Which will be touted as a success for the Artemis project and for public/private cooperation. And it will be.

    With any of them winning, everyone wins.

  11. Yeah, why not?

    If the price is right, eventually a billionaire ought to be capable of buying his/her own Starship + Superheavy kit, to launch on daring escapades to Interplanetary space.

    The same for companies looking for having their own launch services.

    What’s a fact, is that SpaceX will eventually need to leave them go into other owner’s hands.

    And they will have to develop the Starship/SH owner’s manual and train people to perform what they will have to do to keep them working.

    This is an expected development in the commercialization and democratization of space access.

  12. As long as SpaceX can land the Starship on the moon they are going to blow the doors off of the other Artemis competitor designs I have seen.

  13. I imagine the ~$14 mil USD is for a barebones tanker or cargo Starship.

    A crewed one will have many more complex elements raising the price tag to something closer to a modern airliner (life support, habitable spaces, cabins, internal comms and power, etc.).

    Which is fine, the tanker and cargo versions will be the most used ones as well. And a reusable Interplanetary spaceship at the price of a 747 would be a truly remarkable thing.

    But knowing SpaceX and Musk’s plans, they surely are targeting a lower price for crewed Starships, probably keeping it below $100 mil USD.


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