Starship Users Guide

[su27k]

v1.0 can be downloaded from https://www.spacex.com/sites/spacex/files/starship_users_guide_v1.pdf, found by reddit user Russ_Dill

[DreamyPickle]

> 21ton to GTO

That's somewhat unexpected. I remember claims that GTO payload was zero without a separate third stage.

[su27k]

Some interesting tidbits:

1. "The uncrewed Starship allows for the transport of satellites, large observatories, cargo, refueling tanks": separate tank for tanker?

2. "SpaceX is initially planning for two launch sites for the Starship vehicle: Kennedy Space Center LC-39A, Boca Chica launch pad": Well at least this part is clear now.

3. "Payloads are integrated into the Starship fairing vertically in ISO Class 8 (Class 100,000) cleanrooms.
Then the integrated payload stack is transferred to the launch pad and lifted onto the Starship vehicle, while maintaining the same vertical orientation throughout the entire process.": Are they implying the fairing part can be detached from the tank section and re-attached? Not quite sure how else to read it

4. "GTO 21t for single launch": Nice to have this confirmed too

5. "Fully-reusable Starship and Super Heavy systems are expected to allow for space-based activities that have not been possible since the retirement of the Space Shuttle and Space Transportation System or have never been possible before.": Good to see they're not afraid of comparing Starship to Shuttle, this is really the Shuttle 2.0++ folks.

[ThatOldJanxSpirit]

The images are already out of date - leg fairing covers are so last week.

They are still showing the big picture window on the manned version. We’ve sort of assumed that the lox header in the nose killed that off, but that is not necessarily the case. The nose header is needed to bring CoG forward during entry with an empty fairing. The manned version will always have a lot of mass forward so the header could be mounted further aft.

[[email protected]]

> 21ton to GTO

That's somewhat unexpected. I remember claims that GTO payload was zero without a separate third stage.

Except in this article, it's already stated that Starship can lift 20 tons to GTO, but no additional third stage mentioned (and it's logical anyways for 100 tons LEO launch vehicle to be able to launch that amount to GTO)
https://spacenews.com/spacex-targets-2021-commercial-starship-launch/

And Elon has stated (replies to my tweet) that it can lift up to 40 tons to 27°

[soyuzu]

> 21ton to GTO

That's somewhat unexpected. I remember claims that GTO payload was zero without a separate third stage.

Except in this article, it's already stated that Starship can lift 20 tons to GTO, but no additional third stage mentioned (and it's logical anyways for 100 tons LEO launch vehicle to be able to launch that amount to GTO)
https://spacenews.com/spacex-targets-2021-commercial-starship-launch/

And Elon has stated (replies to my tweet) that it can lift up to 30 tons to 27°

More noteworthily, this is RTLS performance. Previously I thought barge landing mentioned in KSC environmental impact assessment has relationship with requirements for single launch to GTO.

These performance numbers assume full Starship reuse, including Super Heavy return to launch site.

Another interesting point is the payload integration method seems explain the insufficient VAB Height

Payloads are integrated into the Starship fairing vertically in ISO Class 8 (Class 100,000) cleanrooms. Then the integrated payload stack is transferred to the launch pad and lifted onto the Starship vehicle, while maintaining the same vertical orientation throughout the entire process. Conditioned air is delivered into the fairing during encapsulated ground processing

[[email protected]]

> 21ton to GTO

That's somewhat unexpected. I remember claims that GTO payload was zero without a separate third stage.

Except in this article, it's already stated that Starship can lift 20 tons to GTO, but no additional third stage mentioned (and it's logical anyways for 100 tons LEO launch vehicle to be able to launch that amount to GTO)
https://spacenews.com/spacex-targets-2021-commercial-starship-launch/

And Elon has stated (replies to my tweet) that it can lift up to 30 tons to 27°

More noteworthily, this is RTLS performance. Previously I thought barge landing mentioned in KSC environmental impact assessment has relationship with requirements for single launch to GTO.

It's more for early launches, so when something goes wrong (you know, landing a 9 m stainless steel vehicle for the first time) they won't be risking the launch site

[mmeijeri]

...and it's logical anyways for 100 tons LEO launch vehicle to be able to launch that amount to GTO...

Why is that logical? What Isp and dry mass are you assuming? I'm getting only ~1700m/s delta-v from LEO assuming 120mT dry mass and 3750 m/s Isp.

[ThatOldJanxSpirit]

...and it's logical anyways for 100 tons LEO launch vehicle to be able to launch that amount to GTO...

Why is that logical? What Isp and dry mass are you assuming? I'm getting only ~1700m/s delta-v from LEO assuming 120mT dry mass and 3750 m/s Isp.

The vehicle launches to LEO with its max 100+ Te payload, it then refuels and boosts it to GTO.

[mmeijeri]

The vehicle launches to LEO with its max 100+ Te payload, it then refuels and boosts it to GTO.

Sure, with refueling, but the 21mT is for a single launch without refueling. Maybe they're still expecting to get the dry mass way below 100mT?

[FutureSpaceTourist]

For ease of reference, a couple of key figures from the user guide

[pochimax]

Payloads are integrated into the Starship fairing vertically in ISO Class 8 (Class 100,000) cleanrooms. Then the integrated payload stack is transferred to the launch pad and lifted onto the Starship vehicle, while maintaining the same vertical orientation throughout the entire process. Conditioned air is delivered into the fairing during encapsulated ground processing

I can believe it. 

[wannamoonbase]

Payloads are integrated into the Starship fairing vertically in ISO Class 8 (Class 100,000) cleanrooms. Then the integrated payload stack is transferred to the launch pad and lifted onto the Starship vehicle, while maintaining the same vertical orientation throughout the entire process. Conditioned air is delivered into the fairing during encapsulated ground processing

I can believe it. 

Seems easier than trying to figure out how to do it horizontally.  That would be a very large hangar and complicated payload handling process to rotate and place and mount into Chomper.  Vertical is a big hangar too but should be able to drop in the payload vertically with a bridge crane.

I admit to at first thinking SS/SH were likely a step to far for SpaceX, or at best much longer in development than proposed.  But Raptor being ready and flight hardware progress of the last year it doesn't seem crazy to think that before the end of 2021 there could be payloads flying to LEO on SS.

[tbellman]

The vehicle launches to LEO with its max 100+ Te payload, it then refuels and boosts it to GTO.

Sure, with refueling, but the 21mT is for a single launch without refueling. Maybe they're still expecting to get the dry mass way below 100mT?

During the presentation in Boca Chica back in September, Elon said something to the effect that he would be very happy if they could bring the dry mass down to 110t, but 120t was more realistic.  If they since have managed to shave it down to less than 100t, that would be a big change.  So the alternative then is that we have underestimated the amount of propellant left when reaching LEO.

Throwing out some ideas, without thinking very detailed about them:

I note that the userguide defines LEO as 500km circular orbit up to 98.9° inclination for the 100+ tonne payload.  That presumably consumes a bit more propellant than a 27° 185km orbit.  Is that enough to explain the different results?

Have calculations for GTO payload assumed stopping in circular LEO first?  Injecting into GTO directly without first circulising in LEO ought to save some Δv.

A couple of days ago, Elon announced that SuperHeavy would be 2m longer.  That's roughly 100t more propellant in the first stage.  How much difference does that make?

Could there be something other than propellant that sets the 100t limit?

(Pet peeve: "mT" means milli-tesla; the proper abbrevation for the metric tonne is "t".)

EDIT: fixed formatting markup

[mmeijeri]

(Pet peeve: "mT" means milli-tesla; the proper abbrevation for the metric tonne is "t".)

Lol, it always felt weird to me too, but I thought that was what US-ians used if they didn't want it confused with short tons.

[Tulse]

I thought this was noteworthy:
"An extended payload volume is also available for payloads requiring up to 22 m of height."

So this and the way the payload gets integrated indicates (as others have noted) that the payload section of Starship will be separated from the propulsion section. Have we seen anything at Boca Chica with the current SNs that would be features involved in the mating and de-mating of these two pieces?

[equiserre]

Does the load factor chart include the accelerations of other than launch? if you compound the accelerations in the lower right corner (2g lateral; -1.5g vertical), the max g during (unpowered) decelerations would be 2.5g and equals an angle of attack of 53 degrees.
Since this is designed to fly at angles of attack up to 90, there are several phases of high lateral acceleration. Is 2g or 2.5g enough for hypersonic bellyflop at 10 km/s? earth point-to-point? high altitude launch abort? especially these last two, with less than orbital speed, usually imply high g´s

[guckyfan]

> 21ton to GTO

That's somewhat unexpected. I remember claims that GTO payload was zero without a separate third stage.

Can someone extrapolate from there if Dear Moon is still possible without refueling? When announced the mission profile did not show any tanker flights.

[waveney]

I thought this was noteworthy:
"An extended payload volume is also available for payloads requiring up to 22 m of height."

This would be a taller Starship!  Maybe another 5-6 Meters tall.

[equiserre]

...and it's logical anyways for 100 tons LEO launch vehicle to be able to launch that amount to GTO...

Why is that logical? What Isp and dry mass are you assuming? I'm getting only ~1700m/s delta-v from LEO assuming 120mT dry mass and 3750 m/s Isp.

I get the same results. 100t to LEO is possible even with a 120t starship. Now 21t to GTO I can´t get it even with an 80t starship.
what is the delta V to a direct GTO as described?