If BFR, then why FalconHeavy?

[ArmchairPhysicist]

Something that has bugged me for a while, any information you pull up on the bfr states that if\when it enters service (likely somewhere in the 2020-2024 range) it will completely replace all current SpaceX rockets. This includes the brand new falcon heavy. From what I can tell, plans to make the ITS and now very serious work to build the BFR have been in the works before falcon heavy became viable. So if the BFR concept has always been planned to replace everything, why did they use all the time and money for Falcon Heavy instead of accelerating the BFR? I can see some logic in being sure you have a heavy/super heavy lifter, just in case BFR got seriously delayed, but the FH resources could have gone towards ensuring the BFR program had a stronger financial backbone and thus more likely to succeed.

[tater]

The point of BFR is not super heavy lifting. The point is heavy payloads to GTO with reusability.

[StrandedonEarth]

And the point of the Heavy was to be able to fly recoverable for missions that would have to expend a single-stick F9. It doesn’t really have the fairing volume to max out the possible payload. The other use would be BLEO missions  

I wonder how many reinforced F9B5H Center Cores they plan on building for the F9H

Edited May 12, 2018 by StrandedonEarth

[NSEP]

BFR and Falcon Heavy have completely different purposes.

Falcon Heavy's primary purpose is to launch Geostationary Communication Satellites at a lower price than Falcon 9. BFR's primary purpose is to build colonies in space.

Falcon Heavy also serves as a back-up for BFR (sort of). If BFR somehow flops, SpaceX could still man-rate Falcon Heavy, and still do missions around the Moon, they could even land on the Moon if they wanted to.

[Jouni]

Falcon Heavy is a real rocket that probably works, at least as far as we can extrapolate from a single data point. The BFR is a hypothetical rocket that may fly one day.

If you want to launch something big and ambitious in the late 2020s, you should start designing the payload now. Right you, you can be fairly certain that there will be an operational launch vehicle at least as capable as Falcon Heavy, so you can design the payload around those capabilities. There may also be bigger and more capable launch vehicles, but you probably don't want to bet $1-2 billion on that.

If SpaceX manages to get the BFR flying on schedule, we will start seeing payloads designed for it in the early 2030s. Until then, they can use the BFR to launch payloads designed for Falcon Heavy, which nobody else can probably launch. Without Falcon Heavy, the BFR would be in direct competition with ordinary launch vehicles such as Ariane 5/6, Atlas V, Delta IV, and Vulcan, because there would not be bigger payloads in the first 10 years or so. That would reduce the price they can charge for the launches significantly.

[tater]

Musk has already said that they think they can get the marginal launch cost of F9 down to ~6M$ (not FH, which would presumably be closer to 10M$). That's pushing us towards $200/kg.

BFR is designed to cannibalize that.

 

[sh1pman]

2 minutes ago, tater said:

Musk has already said that they think they can get the marginal launch cost of F9 down to ~6M$ (not FH, which would presumably be closer to 10M$). That's pushing us towards $200/kg.

BFR is designed to cannibalize that.

 

BFR will be something like 60$/kg. For SpaceX, that is.

[Jouni]

8 minutes ago, tater said:

Musk has already said that they think they can get the marginal launch cost of F9 down to ~6M$ (not FH, which would presumably be closer to 10M$). That's pushing us towards $200/kg.

BFR is designed to cannibalize that.

Marginal costs are not particularly important when the total number of launches is low. SpaceX also needs revenue to cover R&D, facilities, and other investments. If they are competing for payloads that anyone can launch, it will take them much longer to break even.

[NSEP]

39 minutes ago, Jouni said:

If SpaceX manages to get the BFR flying on schedule, we will start seeing payloads designed for it in the early 2030s.

Im pretty sure if BFR will do orbital missions in 2021, payloads (specifically for BFR) would be designed for it shortly afterwards, and be launched in the late 2020s and early 2030s. It really depends on the payloads. Giant space telescopes may take decades to build and design, while Carbon-Fibre space station modules probably takes less than 6 years to design, build and test. (im pretty sure i can design a CF space station module in a single day, building and testing the thing is another story)

Edited May 12, 2018 by NSEP

[tater]

2 hours ago, Jouni said:

Marginal costs are not particularly important when the total number of launches is low. SpaceX also needs revenue to cover R&D, facilities, and other investments. If they are competing for payloads that anyone can launch, it will take them much longer to break even.

Marginal costs are certainly important. I didn’t say marginal cost to the customer.

If a launch of a block 4 cost SpaceX 50M$, and they charged 62, they made 12M$. If the same launch only cost them 6M$, they would have made 56M$.

 

[Kerbart]

How many launches did SpaceX do with FH last year?

How many will they do this year?

How many launches have they done with the BFR?

Answering those questions might hint at why there's a Falcon Heavy

Edited May 13, 2018 by Kerbart

[YNM]

FH is a filler before BFR.

[tater]

1 hour ago, Kerbart said:

How many launches did SpaceX do with FH last year?

How many will they do this year?

How many launches have they done with the BFR?

Answering those questions might hint at why there's a Falcon Heavy

Not really. FH exists to launch payloads that would otherwise require expending a F9 block 5, something they will only rarely want to do.

[kerbiloid]

FH = "lift as much as possible with the same Falcon".
If I can remember, originally it was just "3 Falcons together", but trying to implement this, they have faced the need to reinforce the single module.
Though, it stays a rocket in best traditions of 1950s: "make a bunch of V-2  Baby Sergeant F-9".

BFR is an optimistic attempt to build a many times reusable 1000t-class super-rocket when your 10t-class Falcon from time to time can once reuse the first stage after a half-year of its investigations.

 

5 hours ago, tater said:

Musk has already said that they think they can get the marginal launch cost of F9 down to ~6M$ (not FH, which would presumably be closer to 10M$). That's pushing us towards $200/kg.

Did he say something like that about Tesla?
https://www.wral.com/tesla-s-cash-stockpile-shrank-by-700-000-last-quarter/17526172/

(If NASA had need in Tesla...)

Edited May 13, 2018 by kerbiloid

[Jouni]

3 hours ago, tater said:

Marginal costs are certainly important. I didn’t say marginal cost to the customer.

If a launch of a block 4 cost SpaceX 50M$, and they charged 62, they made 12M$. If the same launch only cost them 6M$, they would have made 56M$.

If they have to compete with other launch vehicle providers, they can charge $62 million for a launch. If the payload is too big for their competitors, they can charge $200 million for the same launch.

Besides, marginal costs can be misleading when the market size is fixed and the market share is large. SpaceX already makes ~25% of orbital launches in the world. Unless they fire most of their employees and close down most of their facilities, they can't reduce their real costs per launch significantly. While that might increase short-term profits, it would also cripple their R&D and production.

[Wjolcz]

As I understand FH was meant to be super heavy but it turned out to be too complicated (regular F9 cores have to be reinforced and stuff) so they decided to go for something simpler: one but bigger rocket.

[tater]

7 hours ago, Jouni said:

If they have to compete with other launch vehicle providers, they can charge $62 million for a launch. If the payload is too big for their competitors, they can charge $200 million for the same launch.

Besides, marginal costs can be misleading when the market size is fixed and the market share is large. SpaceX already makes ~25% of orbital launches in the world. Unless they fire most of their employees and close down most of their facilities, they can't reduce their real costs per launch significantly. While that might increase short-term profits, it would also cripple their R&D and production.

I don't think they leave a lot of money on the table. If their marginal launch costs are 6M, they are in good shape to compete with Blue when NG flies. If their cost is 50M now, and they need to charge at least 55M to pay for all R&D, etc, then 55M is their floor, but that includes all material expenses, not just payroll. Any reduction in marginal costs allows them to drop the price below that floor to the point the material costs per launch are thrown in at least.

[wumpus]

3 hours ago, Wjolcz said:

As I understand FH was meant to be super heavy but it turned out to be too complicated (regular F9 cores have to be reinforced and stuff) so they decided to go for something simpler: one but bigger rocket.

This should have been obvious from early simulations that Falcon wasn't strong enough to support super heavy loads (whether or not they ever got asparagus working).  Falcon Heavy was also made because BFR is still being developed in "Elon Time" and it is hard to know when (or if) it will be ready.

Falcon Heavy presumably can't lift anything significantly heavier than Falcon 9 (although this may have changed with block 5, it needed extra margins), but can presumably lift anything that Falcon 9 expendable lifted to orbit and recover, or send same to LEO/escape by sacrificing only the center stage.

[tater]

FH can loft more mass, the problem is that Falcon 9 is skinny, and there is a functional limit to what you can fit on top. As a result, the bulk of the mass to orbit is in fact stage 2 propellant.

4 hours ago, Wjolcz said:

As I understand FH was meant to be super heavy but it turned out to be too complicated (regular F9 cores have to be reinforced and stuff) so they decided to go for something simpler: one but bigger rocket.

No, the original FH idea was in fact partially cannibalized by F9 itself due to performance improvements, obviating the need for it in many use cases.

The original design could be reusable and put 6400kg to GTO (This is up to 8000kg now). F9 is 5500kg to GTO reusable currently, and  the first F9 could only do ~4500kg to GTO.

[wumpus]

13 minutes ago, tater said:

FH can loft more mass, the problem is that Falcon 9 is skinny, and there is a functional limit to what you can fit on top. As a result, the bulk of the mass to orbit is in fact stage 2 propellant.

Block 5 needed higher margins for NASA man rating, I suspect that block 5 falcon might lift a bit more than expected from block 4 information.  Still, the upper stage appears to be the limiting factor.

[tater]

3 minutes ago, wumpus said:

Block 5 needed higher margins for NASA man rating, I suspect that block 5 falcon might lift a bit more than expected from block 4 information.  Still, the upper stage appears to be the limiting factor.

Yeah, along with the fairing. Even stretched, it's hard to make something 64 tonnes, and fit inside even a significantly longer F9 fairing.

[Jouni]

7 hours ago, tater said:

I don't think they leave a lot of money on the table. If their marginal launch costs are 6M, they are in good shape to compete with Blue when NG flies. If their cost is 50M now, and they need to charge at least 55M to pay for all R&D, etc, then 55M is their floor, but that includes all material expenses, not just payroll. Any reduction in marginal costs allows them to drop the price below that floor to the point the material costs per launch are thrown in at least.

SpaceX wants to increase the prices, not to drop them. Their R&D is constrained by the amount of money they can bring in. Because the total number of launches in the world is not growing very quickly, the best way to bring in more money is to increase the price per launch. Lowering the marginal costs can also help, but the effect is limited, because they can't lower the costs below zero.

[tater]

3 minutes ago, Jouni said:

SpaceX wants to increase the prices, not to drop them. Their R&D is constrained by the amount of money they can bring in. Because the total number of launches in the world is not growing very quickly, the best way to bring in more money is to increase the price per launch. Lowering the marginal costs can also help, but the effect is limited, because they can't lower the costs below zero.

Yeah, but according to what Musk said on that conference call, they are literally looking at a cost reduction on the order of 10X/launch. They have 60M$ for expendable F9, and 50 M$ for reflown. Say the vehicle costs 50M, they make 10M on an expendable launch. As the cost/launch approaches 6M, their profit/launch rises towards 44M$. 4.4X revenues for the same number of flights.

I suppose as they start flying their own constellation, they fly at cost (6M), massively undercutting competitors who have to buy launches retail, which is also a plus.

I don;t see them increasing costs, though I could see all expendable GTO flights eliminated, and the price raised for expendable, new boosters (in favor of making customers buy a FH launch, recoverable).

[Jouni]

2 hours ago, tater said:

Yeah, but according to what Musk said on that conference call, they are literally looking at a cost reduction on the order of 10X/launch. They have 60M$ for expendable F9, and 50 M$ for reflown. Say the vehicle costs 50M, they make 10M on an expendable launch. As the cost/launch approaches 6M, their profit/launch rises towards 44M$. 4.4X revenues for the same number of flights.

It doesn't work that way.

SpaceX employs ~7000 people, which means something like $500 million/year. Their fixed costs are around $1 billion/year, which gives them the capacity to do maybe 25 launches/year. If they want to maintain the expertise and the production capacity they have slowly built over the years, they must pay most of that $1 billion/year, even if they don't launch any rockets at all.

Marginal costs come into play if they want to expand their capacity. Right now, capacity increases would require hiring a lot of new people and building new facilities, which means tens of millions per launch. What SpaceX hopes is that, with increased reusability, their existing infrastructure would be able to support more launches per year. If their current total costs for 25 launches/year are ~$50 million/launch, reducing the marginal costs to $6 million/launch would reduce their total costs for 100 launches/year to ~$15 million/launch.

Unfortunately, nobody wants those additional 75 launches/year at the moment. There are less than 100 launches/year in the world, and SpaceX cannot increase their market share significantly anymore. Many countries want to maintain independent launch capability, barring SpaceX from those launches. Even in the US, NASA and the military will continue using other launch vehicle providers, because they don't want to be stuck with a single company and a single technology.

SpaceX hopes that orbital launches will be much more frequent in the future. That may happen, but the growth is very slow at the moment.

[tater]

They are paying those 7000 people if they net 10M/launch, or if they do the same number of launches and net 44M.

It's hard to extract the marginal costs from their overall labor costs, since their workforce is doing that work already, though some (presumably a small %) are doing pure R&D.

If they make 30 launches, and the cost to do that work drops by an order of magnitude, then they are obviously just using ~10X less labor on those launches (roughly, though some is material costs). As a result, vastly more of those 7000 people are now free to do other work, instead of 90-something % of them making and launching Falcon 9s, a smaller % will be doing that work, and the rest can work on BFR. That's sort of the plan to self-fund BFR.

On top of that, they can hope for more launches via sat constellations, and in addition, there is their own constellation, and they have 6 years to get at least 2200 in orbit according to their license. Getting those launches for 10X cheaper matters.

Edited May 14, 2018 by tater