Impact of SpaceX rideshare on small sat launchers market

[imprezive]

Competitors that intentionally crash at least part of their rockets at the end of each flight.

Imagine being an airliner startup competing with single-use airliners. Doesn’t matter how much money they have… there’s not enough money in the world to crash 22 million airliners each year, which is the number of annual commercial airline flights. Reusable lets you compete in a way nothing else does.

SpaceX, Blue Origin, and Relativity are all working on fully reusable rockets. I would imagine it will come for the others too.

[john smith 19]

That’s not a realistic prospect

Not while the common state of practice is a VTO TSTO vehicle that looks quite a lot like an ICBM on long range radar. 

And SS won't change that.  That's perfectly understandable, given Musk's goal of mars landing. With a surface altitude air pressure  1/140 of earth a winged vehicle of any significant payload (I'd say a payload > 1 tonne in this context) needs enormous wingspan to even let it take off.

But that of course is for later, once SS has started flying.

In the meantime SX will have to be happy with killing off most of the US based sLV competition.

Note another assumption of this thread.

That the US market is basically the entire global launch market.

IRL payloads from several countries would never launch on a US launcher anyway. OTOH they those same countries wouldn't think twice about sticking their payload on a Boeing to fly it to the launch site.

[john smith 19]

Imagine being an airliner startup competing with single-use airliners. Doesn’t matter how much money they have… there’s literally not enough money in the world to crash 20 million airliners each year, which is the number of annual commercial airline flights (the most common airliner is the 737 and it costs $100 million apiece… $2 Quadrillion. That’s 20 times the global annual GDP of $100 trillion). Reusable lets you compete in a way nothing else does.

Indeed. It's only when you look at the situation from this perspective you realise how crippling the single mfg/operator ELV  business model has been to the growth of markets and competition.

Only a government with no viable alternative would bankroll such a concept to begin with.  SS, Stoke Space and Blue's design are all clean-sheet, and IMHO anyone trying to do this has to bake it in from day one.

And until recently only governments could live with the operating costs

And since the rocket is modestly sized and you should get it back after each flight, you shouldn’t necessarily need a ton of capital to make it work. Or even necessarily a lot of people.

But now you face the payload hit of reuse. Musk is saying SS will give a payload fraction of 2% GTOW. That's substantially better than Shuttle, but substantially worse than an ELV (IIRC the Delta IV hit 3.5% despite the what is likely to be a fairly poor structural fraction in the LH2 stg1)

And you still face the technological risk that no one has built anything that looks like a 2nd stage of a standard aspect-ratio TSTO and got it to return from orbital velocity. Or at least from an existing design  

[john smith 19]

Still, this is consistent with your idea that the launch market overall is small, and whatever piece of it you think you can take from SpaceX isn't worth the investment necessary to do so.

The perfect defense against new competitors.

They don't even try to enter the market at no additonal cost to you. 

[Robotbeat]

Imagine being an airliner startup competing with single-use airliners. Doesn’t matter how much money they have… there’s literally not enough money in the world to crash 20 million airliners each year, which is the number of annual commercial airline flights (the most common airliner is the 737 and it costs $100 million apiece… $2 Quadrillion. That’s 20 times the global annual GDP of $100 trillion). Reusable lets you compete in a way nothing else does.

Indeed. It's only when you look at the situation from this perspective you realise how crippling the single mfg/operator ELV  business model has been to the growth of markets and competition.

Only a government with no viable alternative would bankroll such a concept to begin with.  SS, Stoke Space and Blue's design are all clean-sheet, and IMHO anyone trying to do this has to bake it in from day one.

And until recently only governments could live with the operating costs

And since the rocket is modestly sized and you should get it back after each flight, you shouldn’t necessarily need a ton of capital to make it work. Or even necessarily a lot of people.

But now you face the payload hit of reuse. Musk is saying SS will give a payload fraction of 2% GTOW. That's substantially better than Shuttle, but substantially worse than an ELV (IIRC the Delta IV hit 3.5% despite the what is likely to be a fairly poor structural fraction in the LH2 stg1)

And you still face the technological risk that no one has built anything that looks like a 2nd stage of a standard aspect-ratio TSTO and got it to return from orbital velocity. Or at least from an existing design

"No one has done it before" isn't a good argument. There's not a good first-principles argument that a medium lift launch vehicle couldn't accomplish that. I think the scaling laws don't really help you at a big enough scale, and they can actually hurt you.

[RedLineTrain]

Imagine being an airliner startup competing with single-use airliners. Doesn’t matter how much money they have… there’s literally not enough money in the world to crash 20 million airliners each year, which is the number of annual commercial airline flights (the most common airliner is the 737 and it costs $100 million apiece… $2 Quadrillion. That’s 20 times the global annual GDP of $100 trillion). Reusable lets you compete in a way nothing else does.

Indeed. It's only when you look at the situation from this perspective you realise how crippling the single mfg/operator ELV  business model has been to the growth of markets and competition.

Only a government with no viable alternative would bankroll such a concept to begin with.  SS, Stoke Space and Blue's design are all clean-sheet, and IMHO anyone trying to do this has to bake it in from day one.

And until recently only governments could live with the operating costs

And since the rocket is modestly sized and you should get it back after each flight, you shouldn’t necessarily need a ton of capital to make it work. Or even necessarily a lot of people.

But now you face the payload hit of reuse. Musk is saying SS will give a payload fraction of 2% GTOW. That's substantially better than Shuttle, but substantially worse than an ELV (IIRC the Delta IV hit 3.5% despite the what is likely to be a fairly poor structural fraction in the LH2 stg1)

And you still face the technological risk that no one has built anything that looks like a 2nd stage of a standard aspect-ratio TSTO and got it to return from orbital velocity. Or at least from an existing design

Starship has a payload fraction in reusable mode of 3%, right?  150 / 5000 x 100% = 3%.  If necessary, some of that payload fraction can be spent to provide additional safety margin.

For the smaller launchers, we do need to be mindful of the payload fraction.

Regarding the smaller reusable launchers, I'm not sure that they can be competitive.  I have my doubts.  The table stakes for reusable launch are enormous and probably include a captive megaconstellation of the general scope of Starlink.

[john smith 19]

Likely is unrealistic, but not any more so than what some of the diehard Starship fanatics on here say what that vehicle will surely do.

Indeed. Time will tell if such statements are truly visionary, or merely the grossest of wishful thinking. 

One way or another once SS is flying we will get to see who was right. At $1m/launch (assuming all costs are 3x fuel, as the airline industry estimates), that's <$7/Kg.

At $14/Kg that would a 100% gross profit and still be a game changing price.

But such calculations are trivially easy to make. There is zero evidence that SX will operate in that way.

[john smith 19]

Starship has a payload fraction in reusable mode of 3%, right?  150 / 5000 x 100% = 3%.  If necessary, some of that payload fraction can be spent to provide additional safety margin.

AFAIK that's a Wikipedia figure. The SS page on the SX website just says 150t to earth orbit reusable, 250t expendable. The "User Manual" talks about it being an 8m dia vehicle. 

I recall the figure as one Musk gave sometime. IE It's him personally stating it, but I can't recall where. 
IMHO the notion you can build a rocket powered VTO fully reusable LV which will have the same payload fraction as well designed ELV IE 3-3.5%, is highly implausible.

We know what sort of Isp you can get from all the common propellant combinations. We know the vehicle mass for stg2 trades 1:1 for payload and we know  the energy stg2 has to lose from orbit in terms of KE and PE (Kinetic and Potential Energy) is >11x that which the F9 stg1 has to lose.
The combination of things together suggests matching ELV performance will be almost impossible.

TBH I don't think SX believe it's really something customers need to know, so they don't have any great interest in providing it (the length of F9 stages is another set of numbers they don't think anyone outside SX needs to know either). I think it probably changes by the week, if not the day.

For the smaller launchers, we do need to be mindful of the payload fraction.

Regarding the smaller reusable launchers, I'm not sure that they can be competitive.  I have my doubts.  The table stakes for reusable launch are enormous and probably include a captive megaconstellation of the general scope of Starlink.

Actually any LV company who has to raise money from investors has to be mindful of payload fraction. The specific conversation going along the lines of ...

"You want how much to develop a full reusable VTO rocket that can only deliver 50% of what an ELV can? And no one anywhere has developed one of these before (because like Hollywood movie executives, every VC wants to be the second person to have an "original" idea) ? How stupid do I look?"   

[john smith 19]

"No one has done it before" isn't a good argument. There's not a good first-principles argument that a medium lift launch vehicle couldn't accomplish that. I think the scaling laws don't really help you at a big enough scale, and they can actually hurt you.

True. Shuttle did it for starters. Engines contributed at least 10% of GTOW from take off.

Shuttle also has a payload fraction of about 55 000 /3 5000 000 IE 1.57%. The trouble is the hit you take on payload fraction, given for stg 2 vehicle mass trades 1:1 with payload.

As for scaling Charles Poole, a major advocate of microlaunchers, pointed out that the drag issues got much worse as the LV got smaller. I can't recall how he said you could deal with them. 

When I pondered the concept of a "low-risk" SSTO the best I could come up with was a dual-cone sitting on top of a spherical common-bulkhead LO2/LH2 tank [EDIT there's a NASA Tech Brief about hydroforming a cylinder with two flat end caps welded to it into a sphere. Relatively quick, simple, safe and scaleable compared to say explosive forming. Make 2, cut up the second one into 2 pieces, flip the smaller one over and you should have a viable common bulkhead] to drive a set of SSMEs. Maximum volume wrapped with minimum area with a nose design that's had lots of wind tunnel time devoted to it with "sharp end" reentry.

But I could never figure out how to split that into a TSTO. 

[DanClemmensen]

Starship has a payload fraction in reusable mode of 3%, right?  150 / 5000 x 100% = 3%.  If necessary, some of that payload fraction can be spent to provide additional safety margin.

AFAIK that's a Wikipedia figure. The SS page on the SX website just says 150t to earth orbit reusable, 250t expendable. The "User Manual" talks about it being an 8m dia vehicle. 

That 8 m dia in the user manual is the diameter of the payload. The outside diameter of the vehicle is 9 m, but the cargo bay has some pipes and stuff that restrict the payload diameter.

[Robotbeat]

Turn that frown upside down!

[john smith 19]

Starship has a payload fraction in reusable mode of 3%, right?  150 / 5000 x 100% = 3%.  If necessary, some of that payload fraction can be spent to provide additional safety margin.

AFAIK that's a Wikipedia figure. The SS page on the SX website just says 150t to earth orbit reusable, 250t expendable. The "User Manual" talks about it being an 8m dia vehicle. 

That 8 m dia in the user manual is the diameter of the payload. The outside diameter of the vehicle is 9 m, but the cargo bay has some pipes and stuff that restrict the payload diameter.

You're right. It does have the 9m diameter main body. So all payloads are roughly 0.5m away from the skin. I suspect that will also give a surprisingly high reduction in things like noise and heating during ascent. And fixing one side of the fairing simplifies the standard parts but might make the payload a bit more complicated sometime. Neat.

But it's been 3 years since the last release. What's that in Musk time? A decade?

[JayWee]

I do remember during the EverydayAstronaut's youtube interviews Musk mentioned that the first couple of Starships are on the heavier side. So it's not surprising that they payload fraction is not well known at this point. They will work on reducing the mass once the design proves itself.

[john smith 19]

I do remember during the EverydayAstronaut's youtube interviews Musk mentioned that the first couple of Starships are on the heavier side. So it's not surprising that they payload fraction is not well known at this point. They will work on reducing the mass once the design proves itself.

I doubt anyone outside of a fairly small group at SX knows an actual number, and as I said I think it's a very fast moving target. Some days up, some days down.

[RedLineTrain]

I recall the figure as one Musk gave sometime. IE It's him personally stating it, but I can't recall where. 
IMHO the notion you can build a rocket powered VTO fully reusable LV which will have the same payload fraction as well designed ELV IE 3-3.5%, is highly implausible.

Rockets want to be big.  Reusable rockets want to be especially big.

[john smith 19]

I recall the figure as one Musk gave sometime. IE It's him personally stating it, but I can't recall where. 
IMHO the notion you can build a rocket powered VTO fully reusable LV which will have the same payload fraction as well designed ELV IE 3-3.5%, is highly implausible.

Rockets want to be big.  Reusable rockets want to be especially big.

I'm not sure that's an absolute rule. It's just that the only organisatioin making a serious effort to build a VTOL TSTO is building a very big one.

It's impossible to draw a line with a single data point unless you have some kind of equation to describe that line already. 

[RedLineTrain]

I recall the figure as one Musk gave sometime. IE It's him personally stating it, but I can't recall where. 
IMHO the notion you can build a rocket powered VTO fully reusable LV which will have the same payload fraction as well designed ELV IE 3-3.5%, is highly implausible.

Rockets want to be big.  Reusable rockets want to be especially big.

I'm not sure that's an absolute rule. It's just that the only organisatioin making a serious effort to build a VTOL TSTO is building a very big one.

It's impossible to draw a line with a single data point unless you have some kind of equation to describe that line already. 

My point is that the payload mass fraction depends a great deal on size.  The way that SpaceX is matching expendable payload mass fractions with a reusable rocket is by building the reusable rocket very large.

[Robotbeat]

I recall the figure as one Musk gave sometime. IE It's him personally stating it, but I can't recall where. 
IMHO the notion you can build a rocket powered VTO fully reusable LV which will have the same payload fraction as well designed ELV IE 3-3.5%, is highly implausible.

Rockets want to be big.  Reusable rockets want to be especially big.

I'm not sure that's an absolute rule. It's just that the only organisatioin making a serious effort to build a VTOL TSTO is building a very big one.

It's impossible to draw a line with a single data point unless you have some kind of equation to describe that line already. 

My point is that the payload mass fraction depends a great deal on size.  The way that SpaceX is matching expendable payload mass fractions with a reusable rocket is by building the reusable rocket very large.

Only on the very small end where you get hit with aero losses and minimum gauge issues. These aren’t a problem with medium to heavy lift launch vehicles.

In fact, you get penalized at a large enough scale because bending loads and strut loads scale worse than linear at a certain size.

[deltaV]

Only on the very small end where you get hit with aero losses and minimum gauge issues. These aren’t a problem with medium to heavy lift launch vehicles.

In fact, you get penalized at a large enough scale because bending loads and strut loads scale worse than linear at a certain size.

Larger vehicles should have an easier time with reentry heating for two reasons. The first reason is that large vehicles naturally have larger radius curves, which reduces reentry heating. The second reason is that larger vehicles naturally have a lower surface area to mass ratio (square cube law), which reduces the relative mass of insulation or active cooling.

[Robotbeat]

Only on the very small end where you get hit with aero losses and minimum gauge issues. These aren’t a problem with medium to heavy lift launch vehicles.

In fact, you get penalized at a large enough scale because bending loads and strut loads scale worse than linear at a certain size.

Larger vehicles should have an easier time with reentry heating for two reasons. The first reason is that large vehicles naturally have larger radius curves, which reduces reentry heating. The second reason is that larger vehicles naturally have a lower surface area to mass ratio (square cube law), which reduces the relative mass of insulation or active cooling.

the radius helps a bit, BUT The lower surface area to volume ratio actually *hurts* for the same reason that larger objects of the same density have higher terminal velocity.