Author Topic: Falcon 9 Block 5 Updates and Discussion  (Read 486973 times)

Re: F9 Block 5 Updates and Discussion
« Reply #520 on: 03/21/2018 03:18 pm »
I think expendable F9 is more expensive than reusable F9H, so you would need something that maxed out F9H to get into expendable launch territory.

And wouldn't that be a sweet payload to see launch?

Without a payload on the manifest that requires an expendable FH and the rapid reuse Block 5 pending, we shouldn't see any expendable boosters for sometime.  (Pending weather at recovery sites)

These are exciting times!

Hang on, just so I understand correctly, are we saying that any payload that would require an expendable F9 wil automatically shift to a FH? Will the FH launch frequency and risk profile be interchangeable with F9 to the extent that there is no difference between the two from a customer's perspective?

Maybe not right away, but if the Block 5 is close to as quick and affordable to turn around as planned, then yes. 

Even if the cost is nearly equal then it seems from Elon and SpaceX's past behavior would tend toward reuse.
If your core can be reused multiple times, by expending it prematurely you lose much more than the cost to build it. If the core can make them more money with reflights than the customer would pay for an expendable launch why would SpaceX accept to expend their asset? There's a point where it makes financial sense to outright refuse to sell expendable F9 launches, even if it means losing a contract. That point is closer than many think, IMO.
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Offline envy887

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Re: F9 Block 5 Updates and Discussion
« Reply #521 on: 03/21/2018 03:35 pm »
... Will the FH launch frequency and risk profile be interchangeable with F9 to the extent that there is no difference between the two from a customer's perspective?

With 3x booster reuse and a growing number of heavier commsats, FH could reach a reasonable cadence and insurance rate in less than a year. As long as the launch+insurance cost for FH is less than the launch+insurance cost of F9 expendable, customers won't care much about reliability.

So it really comes down to when SpaceX can support, with FH, the 3 or 4 flights a year that are larger than 5.5 tonnes to GTO. I don't think it will take very long after Block 5 is fully implemented.

Offline john smith 19

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Re: F9 Block 5 Updates and Discussion
« Reply #522 on: 03/21/2018 07:19 pm »
If your core can be reused multiple times, by expending it prematurely you lose much more than the cost to build it. If the core can make them more money with reflights than the customer would pay for an expendable launch why would SpaceX accept to expend their asset? There's a point where it makes financial sense to outright refuse to sell expendable F9 launches, even if it means losing a contract. That point is closer than many think, IMO.
Unlikely to be an issue right now. IIRC SX have a bunch of cores at 2 flights, so a 3rd expendable flight in expendable mode is perfectly feasible. Stripping any recovery hardware that can be stripped, not sending out the recovery ships all cuts the cost of that launch.

But that's the situation now.

As the inventory "flies out" all cores left are Block 5 and now you have to fly 9 times, otherwise you don't just lose the core, you lose the revenue from however many more launches it had left.

Worst case in expendable mode you don't lose a $25m core, SX lose $567m in revenue from the next 9 launches SX were going to have with it.

IOW there will come a time when if you want the maximum payload/delta v range you'll either be asked to pay a premium (at a minimum the cost of a replacement F9 stage) or you'll be asked to shift it to FH (remember I'm assuming there will be point where all boosters are Blk5, including the FH ones).

And I'd expect that won't be the F9 price, it will be the FH price to do so.

But that won't happen till the the existing previous blocks have hit EoL.





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Re: F9 Block 5 Updates and Discussion
« Reply #523 on: 03/21/2018 07:39 pm »
If you built a Block 5 launch vehicle for $50M and sold the expendable launch for $90M you'd make a nice profit, loss of future uses has nothing to do with it unless your production capacity wouldn't allow you to make enough boosters to service your other customers.
« Last Edit: 03/21/2018 07:40 pm by gongora »

Offline envy887

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Re: F9 Block 5 Updates and Discussion
« Reply #524 on: 03/21/2018 07:43 pm »
If you built a Block 5 launch vehicle for $50M and sold the expendable launch for $90M you'd make a nice profit, loss of future uses has nothing to do with it unless your production capacity wouldn't allow you to make enough boosters to service your other customers.

Which could be a problem if SpaceX is trying to move production resources to making more upper stages, or to making BFR/BFS.

Offline M.E.T.

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Re: F9 Block 5 Updates and Discussion
« Reply #525 on: 03/21/2018 07:46 pm »
If your core can be reused multiple times, by expending it prematurely you lose much more than the cost to build it. If the core can make them more money with reflights than the customer would pay for an expendable launch why would SpaceX accept to expend their asset? There's a point where it makes financial sense to outright refuse to sell expendable F9 launches, even if it means losing a contract. That point is closer than many think, IMO.
Unlikely to be an issue right now. IIRC SX have a bunch of cores at 2 flights, so a 3rd expendable flight in expendable mode is perfectly feasible. Stripping any recovery hardware that can be stripped, not sending out the recovery ships all cuts the cost of that launch.

But that's the situation now.

As the inventory "flies out" all cores left are Block 5 and now you have to fly 9 times, otherwise you don't just lose the core, you lose the revenue from however many more launches it had left.

Worst case in expendable mode you don't lose a $25m core, SX lose $567m in revenue from the next 9 launches SX were going to have with it.

IOW there will come a time when if you want the maximum payload/delta v range you'll either be asked to pay a premium (at a minimum the cost of a replacement F9 stage) or you'll be asked to shift it to FH (remember I'm assuming there will be point where all boosters are Blk5, including the FH ones).

And I'd expect that won't be the F9 price, it will be the FH price to do so.

But that won't happen till the the existing previous blocks have hit EoL.

It will also depend on how many flights your Block 5 fleet have done. Just like there are Block 3 cores now that have done two flights and are at the point of retirement, there will eventually be Block 5 cores that have done 9 flights, and can potentially be expended at their next flight.

I imagine that point won't be reached before the end of 2019 or perhaps even 2020, however, depending on how many Block 5 boosters they end up constructing. Assuming about 20 Block 5 launches in 2018, and then even if only 5 Block 5's are constructed this year, that would only give you about 4 flights per Block 5 in 2018.

So they won't even be halfway through their useful lives by the end of the year. So it would take a while to get to 9 flights for a Block 5 booster, but that will happen, eventually, at which point it can probably be expended without much of an opportunity cost being incurred.

EDIT

In fact, simplistically one can say that on average, every 10th launch a Block 5 booster can be expended, given that 10 flights use up one booster. And one assumes that the boosters will be used in staggered fashion so that not all of them reach launch 10 at the same approximate time. So going with this ratio, it means that 10% of your launches in a given year can be expendable. So 3 expendable launches in a 30 launch year, 4 expendable launches in a 40 launch year, etc.

These would be 4 launches taken away from what otherwise would have been the FH manifest, thus potentially reducing the need for FH even further.
« Last Edit: 03/21/2018 08:00 pm by M.E.T. »

Offline aero

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Re: F9 Block 5 Updates and Discussion
« Reply #526 on: 03/21/2018 08:15 pm »
Good points there, but wouldn't they get more Block 5 reliability data sooner by driving the first one to end of life as soon as they can make 10 launches from a single location? That would allow correction of problems to be made at the factory earlier in the production run although we know that there will be a few Block 5's produced before the next 10 launches happen. Those Block 5's would need to be retrofitted or expended depending on the severity of the problems discovered.
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Offline AncientU

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Re: F9 Block 5 Updates and Discussion
« Reply #527 on: 03/21/2018 08:25 pm »
If your core can be reused multiple times, by expending it prematurely you lose much more than the cost to build it. If the core can make them more money with reflights than the customer would pay for an expendable launch why would SpaceX accept to expend their asset? There's a point where it makes financial sense to outright refuse to sell expendable F9 launches, even if it means losing a contract. That point is closer than many think, IMO.
Unlikely to be an issue right now. IIRC SX have a bunch of cores at 2 flights, so a 3rd expendable flight in expendable mode is perfectly feasible. Stripping any recovery hardware that can be stripped, not sending out the recovery ships all cuts the cost of that launch.

But that's the situation now.

As the inventory "flies out" all cores left are Block 5 and now you have to fly 9 times, otherwise you don't just lose the core, you lose the revenue from however many more launches it had left.

Worst case in expendable mode you don't lose a $25m core, SX lose $567m in revenue from the next 9 launches SX were going to have with it.

IOW there will come a time when if you want the maximum payload/delta v range you'll either be asked to pay a premium (at a minimum the cost of a replacement F9 stage) or you'll be asked to shift it to FH (remember I'm assuming there will be point where all boosters are Blk5, including the FH ones).

And I'd expect that won't be the F9 price, it will be the FH price to do so.

But that won't happen till the the existing previous blocks have hit EoL.

It will also depend on how many flights your Block 5 fleet have done. Just like there are Block 3 cores now that have done two flights and are at the point of retirement, there will eventually be Block 5 cores that have done 9 flights, and can potentially be expended at their next flight.

I imagine that point won't be reached before the end of 2019 or perhaps even 2020, however, depending on how many Block 5 boosters they end up constructing. Assuming about 20 Block 5 launches in 2018, and then even if only 5 Block 5's are constructed this year, that would only give you about 4 flights per Block 5 in 2018.

So they won't even be halfway through their useful lives by the end of the year. So it would take a while to get to 9 flights for a Block 5 booster, but that will happen, eventually, at which point it can probably be expended without much of an opportunity cost being incurred.

EDIT

In fact, simplistically one can say that on average, every 10th launch a Block 5 booster can be expended, given that 10 flights use up one booster. And one assumes that the boosters will be used in staggered fashion so that not all of them reach launch 10 at the same approximate time. So going with this ratio, it means that 10% of your launches in a given year can be expendable. So 3 expendable launches in a 30 launch year, 4 expendable launches in a 40 launch year, etc.

These would be 4 launches taken away from what otherwise would have been the FH manifest, thus potentially reducing the need for FH even further.

You are assuming that a booster's useful life is ten flights.  This is not as explained by SpaceX.  They have repeatedly stated that Block 5 should do around ten flights before major refurbishment, not end of life.  What the major refurbishment will cost (time/$$$s) is not yet known, but it must be expected to be less than a new core -- probably by a lot like the first reflights were -- or they'd not consider refurbishment.  Between launches, there should be vanishingly little work to do to turn around a core.
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Offline Nomadd

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Re: F9 Block 5 Updates and Discussion
« Reply #528 on: 03/21/2018 08:28 pm »
 Wasn't the quote ten flights before minor refurbishment?
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Offline M.E.T.

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Re: F9 Block 5 Updates and Discussion
« Reply #529 on: 03/21/2018 08:30 pm »
If your core can be reused multiple times, by expending it prematurely you lose much more than the cost to build it. If the core can make them more money with reflights than the customer would pay for an expendable launch why would SpaceX accept to expend their asset? There's a point where it makes financial sense to outright refuse to sell expendable F9 launches, even if it means losing a contract. That point is closer than many think, IMO.
Unlikely to be an issue right now. IIRC SX have a bunch of cores at 2 flights, so a 3rd expendable flight in expendable mode is perfectly feasible. Stripping any recovery hardware that can be stripped, not sending out the recovery ships all cuts the cost of that launch.

But that's the situation now.

As the inventory "flies out" all cores left are Block 5 and now you have to fly 9 times, otherwise you don't just lose the core, you lose the revenue from however many more launches it had left.

Worst case in expendable mode you don't lose a $25m core, SX lose $567m in revenue from the next 9 launches SX were going to have with it.

IOW there will come a time when if you want the maximum payload/delta v range you'll either be asked to pay a premium (at a minimum the cost of a replacement F9 stage) or you'll be asked to shift it to FH (remember I'm assuming there will be point where all boosters are Blk5, including the FH ones).

And I'd expect that won't be the F9 price, it will be the FH price to do so.

But that won't happen till the the existing previous blocks have hit EoL.

It will also depend on how many flights your Block 5 fleet have done. Just like there are Block 3 cores now that have done two flights and are at the point of retirement, there will eventually be Block 5 cores that have done 9 flights, and can potentially be expended at their next flight.

I imagine that point won't be reached before the end of 2019 or perhaps even 2020, however, depending on how many Block 5 boosters they end up constructing. Assuming about 20 Block 5 launches in 2018, and then even if only 5 Block 5's are constructed this year, that would only give you about 4 flights per Block 5 in 2018.

So they won't even be halfway through their useful lives by the end of the year. So it would take a while to get to 9 flights for a Block 5 booster, but that will happen, eventually, at which point it can probably be expended without much of an opportunity cost being incurred.

EDIT

In fact, simplistically one can say that on average, every 10th launch a Block 5 booster can be expended, given that 10 flights use up one booster. And one assumes that the boosters will be used in staggered fashion so that not all of them reach launch 10 at the same approximate time. So going with this ratio, it means that 10% of your launches in a given year can be expendable. So 3 expendable launches in a 30 launch year, 4 expendable launches in a 40 launch year, etc.

These would be 4 launches taken away from what otherwise would have been the FH manifest, thus potentially reducing the need for FH even further.

You are assuming that a booster's useful life is ten flights.  This is not as explained by SpaceX.  They have repeatedly stated that Block 5 should do around ten flights before major refurbishment, not end of life.  What the major refurbishment will cost (time/$$$s) is not yet known, but it must be expected to be less than a new core -- probably by a lot like the first reflights were -- or they'd not consider refurbishment.  Between launches, there should be vanishingly little work to do to turn around a core.

True. I just question whether they will go from a maximum of 2 flights per core (current record) straight to 100 flights per core. It might take a few years to get to that point. 10 flights is already a quantum leap forward.

And if it takes a few years to work out the kinks, or maybe it requires a Block 6 to get beyond 10 flights, well, by then BFR will almost be here, and it becomes a moot point. For practical purposes a 10 reuse capability seems reasonable. At least for the next 2-3 years.

Offline wannamoonbase

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Re: F9 Block 5 Updates and Discussion
« Reply #530 on: 03/21/2018 09:57 pm »
True. I just question whether they will go from a maximum of 2 flights per core (current record) straight to 100 flights per core. It might take a few years to get to that point. 10 flights is already a quantum leap forward.

And if it takes a few years to work out the kinks, or maybe it requires a Block 6 to get beyond 10 flights, well, by then BFR will almost be here, and it becomes a moot point. For practical purposes a 10 reuse capability seems reasonable. At least for the next 2-3 years.

I agree, the design needs to be proven.  If they eventually get to 10 in the next 1-2 years that would be significant.  I don't think they will get right away, but they'll adapt and get it as far as physics allow relatively soon.

Customer acceptance of cores with each successive launch maybe the most time consuming part in the process.

I'm not sure there is much need to go above 10 launches per core if the most they manifest is 30-40 launches per year.  That's alot of upper stages, but they'll need to maintain an ability to make Merlin 1D's and boosters.
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Re: F9 Block 5 Updates and Discussion
« Reply #531 on: 03/21/2018 10:20 pm »
I'm not sure there is much need to go above 10 launches per core if the most they manifest is 30-40 launches per year.  That's alot of upper stages, but they'll need to maintain an ability to make Merlin 1D's and boosters.
Starlink alone needs more-or-less a hundred launches, over 3 years or so itself, so that'd more or less double '30-40' - at least until BFR.

Offline vaporcobra

Re: F9 Block 5 Updates and Discussion
« Reply #532 on: 03/21/2018 10:33 pm »
Wasn't the quote ten flights before minor refurbishment?

Of course this is coming from Elon Musk, but he said this in the SES-10 post-launch conference.
Quote
Question: How many times might you be able to reuse one of the boosters, both for one that’s been reworked, a lot like this one, and one that has undergone minimal refurbishment?

Elon: Sure. The design intent is that the rocket can be reflown with zero hardware changes. In other words, the only thing that changes is you reload propellant 10 times. And then with moderate refurbishment that doesn’t have a significant effect on the cost, it can be reflown at least 100 times. Actually, really, I mean, we could make it 1,000 but it’s probably not – there’s no point in that, I think. (Laughter.)

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Re: F9 Block 5 Updates and Discussion
« Reply #533 on: 03/22/2018 01:21 pm »
Are there estimates on how long the burns are going to be the Block 5 Booster and US?

They've got to be shorter, but by how much?
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Re: F9 Block 5 Updates and Discussion
« Reply #534 on: 03/22/2018 02:03 pm »
As the inventory "flies out" all cores left are Block 5 and now you have to fly 9 times, otherwise you don't just lose the core, you lose the revenue from however many more launches it had left.

Worst case in expendable mode you don't lose a $25m core, SX lose $567m in revenue from the next 9 launches SX were going to have with it.

I don't see it like that. Because the cost to MAKE a new Block 5 is less than $567m, the maximum amount SpaceX would lose is the cost to replace the booster with a new one, plus any delay costs. But of course, they won't lose it - it will be charged to the customer.

Presumably they could also, if required, which I doubt, make a block 5 with no recovery hardware. Which makes them even cheaper.

So the most it would cost a customer to have an expendable flight, is the cost of a *new* booster plus whatever SpaceX add on as costs and profit.

Offline scdavis

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Re: F9 Block 5 Updates and Discussion
« Reply #535 on: 03/22/2018 02:15 pm »
As the inventory "flies out" all cores left are Block 5 and now you have to fly 9 times, otherwise you don't just lose the core, you lose the revenue from however many more launches it had left.

Worst case in expendable mode you don't lose a $25m core, SX lose $567m in revenue from the next 9 launches SX were going to have with it.

I don't see it like that. Because the cost to MAKE a new Block 5 is less than $567m, the maximum amount SpaceX would lose is the cost to replace the booster with a new one, plus any delay costs. But of course, they won't lose it - it will be charged to the customer.

Presumably they could also, if required, which I doubt, make a block 5 with no recovery hardware. Which makes them even cheaper.

So the most it would cost a customer to have an expendable flight, is the cost of a *new* booster plus whatever SpaceX add on as costs and profit.

Exactly - it's only a loss if they are production-limited by either staff or physical space constraints. In other words -- it's a normal business decision. If they have the ability to hire additional production staff and have space for production, they could choose to expend F9 first stages for the simple marginal profit between cost of production and customer price. $20m profit is still profit and nothing to sneeze at. We don't know their full-up cost difference between FH-R and F9-E... at this point, they will have an idea but may not know for sure either.

My guess - they will act like a normal business and optimize for profit, with the exception that they are prioritizing BFS/BFR development. They will set FH and F9-E prices to drive the customer behavior that maximizes profit, within their production capability. Why wouldn't they?

Offline john smith 19

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Re: F9 Block 5 Updates and Discussion
« Reply #536 on: 03/24/2018 09:02 pm »
I don't see it like that. Because the cost to MAKE a new Block 5 is less than $567m, the maximum amount SpaceX would lose is the cost to replace the booster with a new one, plus any delay costs. But of course, they won't lose it - it will be charged to the customer.
You're missing one small detail in this.

Musk wants to shift all launches to BFR.

They don't want to retain any F9 booster mfg capacity at all and if there's one thing we'll learned about SX by now it's they don't keep "spare" stages lying around.

So flying an F9 booster as an expendable is a very big deal unless it's at end-of-life.

Now that quote by Musk, saying blk 5 has got a potential life of 100s of launches with minor refurb just pushes the SX further away from wanting fly any expendable missions on a blk 5.

So if you want near max capacity on F9 payload or delta V (especially if it's both) I'd expect them to say "you'll have to use FH"

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Offline guckyfan

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Re: F9 Block 5 Updates and Discussion
« Reply #537 on: 03/24/2018 10:14 pm »
If you assume 100 possible launches per booster then you can fly all payloads until replaced by BFR with 3 or 4 boosters. They will have more than 20 before all customers accept reuse, including NASA for crew and Airforce. That means they can well afford to lose a few.

Offline M.E.T.

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Re: F9 Block 5 Updates and Discussion
« Reply #538 on: 03/25/2018 07:34 am »
I don't see it like that. Because the cost to MAKE a new Block 5 is less than $567m, the maximum amount SpaceX would lose is the cost to replace the booster with a new one, plus any delay costs. But of course, they won't lose it - it will be charged to the customer.
You're missing one small detail in this.

Musk wants to shift all launches to BFR.

They don't want to retain any F9 booster mfg capacity at all and if there's one thing we'll learned about SX by now it's they don't keep "spare" stages lying around.

So flying an F9 booster as an expendable is a very big deal unless it's at end-of-life.

Now that quote by Musk, saying blk 5 has got a potential life of 100s of launches with minor refurb just pushes the SX further away from wanting fly any expendable missions on a blk 5.

So if you want near max capacity on F9 payload or delta V (especially if it's both) I'd expect them to say "you'll have to use FH"

I think that was an aspirational goal, and that Shotwell has subsequently said that there will be an extensive overlap between BFR and F9 services until all customers are comfortable with the shift. The "stock up on F9 cores and shift production exclusively to BFR" was never going to work. Sure, in the end, BFR will replace F9 completely, but I expect at least 5 years of dual production of the two systems. I don't really see how it could work practically otherwise.


Offline OneSpeed

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Re: F9 Block 5 Updates and Discussion
« Reply #539 on: 03/25/2018 08:34 am »
Are there estimates on how long the burns are going to be the Block 5 Booster and US?

They've got to be shorter, but by how much?

If the block 4 booster is at 92% thrust, and block 5 at 100%, then because thrust is proportional to mass flow, you might assume the block 5 burns would take 92% of the block 4 times. However, the throttle back at launch, for Max-Q, and to limit acceleration before MECO all still need to occur, and would all reduce the difference. I'm guessing they'll be around 95% of the block 4 burn times. I'm not sure yet if the S2 thrust will change as much.

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