SpaceX Falcon Heavy Demo - Discussion and Speculation

[Owlon]

They dont expect any circumstance where the center core will ever be RTLS. Too far downrange to come back.

Is this new information from SpaceX or speculation? Reasonably accurate simulations by posters here suggest that FH can get upwards of 8 tons to GTO and 20-something to LEO with all three cores doing RTLS. That covers the vast majority of the existing market.

[gongora]

They may be waiting to get some flight history with FH and Block 5 before deciding whether FH would really be worth it for 7 ton payloads.

[LouScheffer]

They may be waiting to get some flight history with FH and Block 5 before deciding whether FH would really be worth it for 7 ton payloads.

The decisions SpaceX makes for 7 tonne payloads will be a excellent data point on the true cost of re-use, as determined by rational analysis of the economics by the folks who have all the data.  Same vendor, same hardware, identical upper stage - just two different ways of performing the same mission, one re-usable and one expendable.

They can either expend one core, or recover and re-use three.   If they go for FH, then the cost of recovery and re-use is less than 1/3 the cost of a new core.   Otherwise they will go expendable.

And if they "normally" do FH, but sometimes do expendable with an old core, that would tell what the lifetime of a core.  Or at least that after another flight, they'd need a more expensive refurbishment than usual (just like airlines plan to retire aircraft just before a 'D" check).

[Nate_Trost]

I would think not just cost of re-use, but additional costs in manpower and processing overhead for a FH launch campaign versus F9. I wonder if FH only flies a couple times a year on missions that are too heavy for F9 expendable, because the 'sweet spot' is actually just flying a F9 expendable mission using a reflown first stage versus a FH campaign.

[M.E.T.]

I would think not just cost of re-use, but additional costs in manpower and processing overhead for a FH launch campaign versus F9. I wonder if FH only flies a couple times a year on missions that are too heavy for F9 expendable, because the 'sweet spot' is actually just flying a F9 expendable mission using a reflown first stage versus a FH campaign.

Well, if they make a low enough quantity of Block 5's, it would only take about 10 flights before a Block 5 reaches its sell by date. Plus they will still have almost a dozen Block 3 and 4 returned cores sitting in their warehouse. And these are apparently only good for 3 or so reuses.

So, take say 10 returned Block 3 and 4 cores that have one more expendable flight in them, and add to that a Block 5 reaching the end of its useful life every 10 flights or so, and you will have about a dozen F9 cores available in 2018 that will be on their last flight and can be used in expendable format very cheaply.

So those would cover the majority of 7-8 ton GTO payloads for the foreseeable future, really cutting down on the need to use FH in reusable configuration.

And if they get up to say 50 F9 flights per year, and assuming 10 flights per Block 5, that would make another 5 cores available for expendable flights per year, every year. Meaning five 7-8 ton GTO payloads that can be flown on expendable F9's every year, without needing to use the FH.

How would this affect the business case for FH in terms of economies of scale?

[AncientU]

I would think not just cost of re-use, but additional costs in manpower and processing overhead for a FH launch campaign versus F9. I wonder if FH only flies a couple times a year on missions that are too heavy for F9 expendable, because the 'sweet spot' is actually just flying a F9 expendable mission using a reflown first stage versus a FH campaign.

Well, if they make a low enough quantity of Block 5's, it would only take about 10 flights before a Block 5 reaches its sell by date. Plus they will still have almost a dozen Block 3 and 4 returned cores sitting in their warehouse. And these are apparently only good for 3 or so reuses.

So, take say 10 returned Block 3 and 4 cores that have one more expendable flight in them, and add to that a Block 5 reaching the end of its useful life every 10 flights or so, and you will have about a dozen F9 cores available in 2018 that will be on their last flight and can be used in expendable format very cheaply.

So those would cover the majority of 7-8 ton GTO payloads for the foreseeable future, really cutting down on the need to use FH in reusable configuration.

And if they get up to say 50 F9 flights per year, and assuming 10 flights per Block 5, that would make another 5 cores available for expendable flights per year, every year. Meaning five 7-8 ton GTO payloads that can be flown on expendable F9's every year, without needing to use the FH.

How would this affect the business case for FH in terms of economies of scale?

Block 5 needs refurbishment after 10-12 flights, not retirement.

[M.E.T.]

Yes that is the goal.

I just find the jump from the maximum of one reuse we saw in 2017, to ten reuses in 2018 already a bit of a stretch. To think that they are going straight to 100 reuses on the Block 5 seems a bit unlikely to me. Maybe a few years down the line they wil perfect the design.

But by then ITSy might be just around the corner, changing the whole game again.

[Semmel]

I would think not just cost of re-use, but additional costs in manpower and processing overhead for a FH launch campaign versus F9. I wonder if FH only flies a couple times a year on missions that are too heavy for F9 expendable, because the 'sweet spot' is actually just flying a F9 expendable mission using a reflown first stage versus a FH campaign.

Well, if they make a low enough quantity of Block 5's, it would only take about 10 flights before a Block 5 reaches its sell by date. Plus they will still have almost a dozen Block 3 and 4 returned cores sitting in their warehouse. And these are apparently only good for 3 or so reuses.

So, take say 10 returned Block 3 and 4 cores that have one more expendable flight in them, and add to that a Block 5 reaching the end of its useful life every 10 flights or so, and you will have about a dozen F9 cores available in 2018 that will be on their last flight and can be used in expendable format very cheaply.

So those would cover the majority of 7-8 ton GTO payloads for the foreseeable future, really cutting down on the need to use FH in reusable configuration.

And if they get up to say 50 F9 flights per year, and assuming 10 flights per Block 5, that would make another 5 cores available for expendable flights per year, every year. Meaning five 7-8 ton GTO payloads that can be flown on expendable F9's every year, without needing to use the FH.

How would this affect the business case for FH in terms of economies of scale?

beside the GTO market, the most use for FH would be deep space missions or GTO with more than 8 mT, for example for DOD. Other than that, it seems FH does not have much justification left. One good reason to keep it in the past was red dragon. Since that is canceled, I struggle to find good justification for FH.

Ok, so FH gives SpaceX capabilities that a F9 can not fulfill. Are the cases where this capability is actually needed enough to justify FH? Probably not. But at the time they started FH, this was an absolute yes. Times change.

Second consideration: FH steps in to prevent the use of expendable F9 flights. Does this justify the development of FH? Probably not. The number of expendable flights is very limited for F9. And if ITSy comes online in the next 3 to 5 years, I would say that FH was an unnecessary money sink, at least for GTO missions. But that could not have been known at the time where the decision to go for FH was made.

Why does SpaceX not cancel FH? Too much invested already? They didnt follow that fallacy in the past. Do they need FH for LEO performance? If so, for what? The only thing that I can come up with at moment is: Tourists around the Moon and some DOD flights. Is that enough to justify FH financially? Someone smarter than me will have to answer that. Is it enough to justify FH emotionally? Maybe. If it starts flying tourists around the Moon, this could have a very positive effect politically. Is this enough to justify FH? Dont know. Hmm...

[M.E.T.]

I would think not just cost of re-use, but additional costs in manpower and processing overhead for a FH launch campaign versus F9. I wonder if FH only flies a couple times a year on missions that are too heavy for F9 expendable, because the 'sweet spot' is actually just flying a F9 expendable mission using a reflown first stage versus a FH campaign.

Well, if they make a low enough quantity of Block 5's, it would only take about 10 flights before a Block 5 reaches its sell by date. Plus they will still have almost a dozen Block 3 and 4 returned cores sitting in their warehouse. And these are apparently only good for 3 or so reuses.

So, take say 10 returned Block 3 and 4 cores that have one more expendable flight in them, and add to that a Block 5 reaching the end of its useful life every 10 flights or so, and you will have about a dozen F9 cores available in 2018 that will be on their last flight and can be used in expendable format very cheaply.

So those would cover the majority of 7-8 ton GTO payloads for the foreseeable future, really cutting down on the need to use FH in reusable configuration.

And if they get up to say 50 F9 flights per year, and assuming 10 flights per Block 5, that would make another 5 cores available for expendable flights per year, every year. Meaning five 7-8 ton GTO payloads that can be flown on expendable F9's every year, without needing to use the FH.

How would this affect the business case for FH in terms of economies of scale?

beside the GTO market, the most use for FH would be deep space missions or GTO with more than 8 mT, for example for DOD. Other than that, it seems FH does not have much justification left. One good reason to keep it in the past was red dragon. Since that is canceled, I struggle to find good justification for FH.

Ok, so FH gives SpaceX capabilities that a F9 can not fulfill. Are the cases where this capability is actually needed enough to justify FH? Probably not. But at the time they started FH, this was an absolute yes. Times change.

Second consideration: FH steps in to prevent the use of expendable F9 flights. Does this justify the development of FH? Probably not. The number of expendable flights is very limited for F9. And if ITSy comes online in the next 3 to 5 years, I would say that FH was an unnecessary money sink, at least for GTO missions. But that could not have been known at the time where the decision to go for FH was made.

Why does SpaceX not cancel FH? Too much invested already? They didnt follow that fallacy in the past. Do they need FH for LEO performance? If so, for what? The only thing that I can come up with at moment is: Tourists around the Moon and some DOD flights. Is that enough to justify FH financially? Someone smarter than me will have to answer that. Is it enough to justify FH emotionally? Maybe. If it starts flying tourists around the Moon, this could have a very positive effect politically. Is this enough to justify FH? Dont know. Hmm...

Or they know ITSy is much furher away than most people believe right now.

[abaddon]

A (Heavy) bird on the pad is worth two ITSys in the bush, or something.

[AncientU]

There must be good justification, or a FH flight with considerable cost and risk wouldn't still be on the table.  Could be that Block 5 has features (titanium grid fins, for example) that are only worth investment if the vehicle flies repeatedly.  Expendable Block 3/4s may be cost effective, but expending a Block 5 (with dozens of potential future flights at something like a 50% margin) is just something to be avoided at all costs.

[M.E.T.]

There must be good justification, or a FH flight with considerable cost and risk wouldn't still be on the table.  Could be that Block 5 has features (titanium grid fins, for example) that are only worth investment if the vehicle flies repeatedly.  Expendable Block 3/4s may be cost effective, but expending a Block 5 (with dozens of potential future flights at something like a 50% margin) is just something to be avoided at all costs.

Most likely refurbishing Blocks 3 and 4 is too expensive, even for a single reflight,  and Block 5 is planned for more than 10 reuses very soon.

[GWH]

They dont expect any circumstance where the center core will ever be RTLS. Too far downrange to come back.

Is this new information from SpaceX or speculation? Reasonably accurate simulations by posters here suggest that FH can get upwards of 8 tons to GTO and 20-something to LEO with all three cores doing RTLS. That covers the vast majority of the existing market.

Worth noting that this payload is the absolute upper limit of single commercial comsats, and if all RTLS the re-entry environment for all 3 cores should be more passive than an aggressive downrange landing.

[guckyfan]

I think justification for FH is the new EELV contract, if nothing else. They need to show how they can fly all required profiles. They won't get into that contract by stating they will have ITSy.

So it is FH or not applying for EELV. Which would probably make the Airforce and DoD unhappy.

[guckyfan]

Most likely refurbishing Blocks 3 and 4 is too expensive, even for a single reflight,  and Block 5 is planned for more than 10 reuses very soon.

They stated quite clearly that even the first reflight did make them money despite all the first time cost. Subsequent flights are more economical. But reuse only starts ramping up. They don't need more than 1 reflight per core. I doubt they will want to fly block 3 and block 4 cores once they have block 5 for operational reasons. So there is no reason to push it now.

They have fired one core, the most heavily stressed core even, 8 times without refurbishment except they changed a few seals to their presently used material before the first refire.

[M.E.T.]

Most likely refurbishing Blocks 3 and 4 is too expensive, even for a single reflight,  and Block 5 is planned for more than 10 reuses very soon.

They stated quite clearly that even the first reflight did make them money despite all the first time cost. Subsequent flights are more economical. But reuse only starts ramping up. They don't need more than 1 reflight per core. I doubt they will want to fly block 3 and block 4 cores once they have block 5 for operational reasons. So there is no reason to push it now.

They have fired one core, the most heavily stressed core even, 8 times without refurbishment except they changed a few seals to their presently used material before the first refire.

Sorry, I wasn't clear with what I meant in that post.

I know that refurbishing a Block 3 or 4 is cheaper than constructing a brand new core, but it might not be cheaper than flying a fully reusable FH. In which case the business case for using FH instead of an expendable Block 3 or 4 would exist.

Of course, that's just speculation on my part to try and increase the justification for FH even in the short term.

[llanitedave]

They dont expect any circumstance where the center core will ever be RTLS. Too far downrange to come back.

The last launch had a pretty lofted trajectory.  I would never say never.

[wannamoonbase]

I think justification for FH is the new EELV contract, if nothing else. They need to show how they can fly all required profiles. They won't get into that contract by stating they will have ITSy.

So it is FH or not applying for EELV. Which would probably make the Airforce and DoD unhappy.

The FH can certainly handle some paying payloads and be profitable.  But importantly it provides a wider portfolio of possible missions.  Such as the touristy lunar flyby. 

However, the largest DOD missions should be a very profitable target to pursue.

It doesn't hurt to have the capability.

[LouScheffer]

[...] DOD flights. Is that enough to justify FH financially?

It very well could be.  SpaceX could probably bid $250 million each and still beat Delta-IV heavy.  Not sure they would be willing to do this, since it could strain their relationship with the DOD if commercial prices are much less.   But just a few of these launches could repay development costs.

[M.E.T.]

Is there a practical limit in terms of how far away the ASDS can catch a returning centre core? Because if the side boosters impart the maximum possible assistance to the rocket, allowing the centre core to retain the maximum amount of fuel for use after side booster separation, I guess you want the centre core to keep thrusting for as long as possible before it separates from the second stage.

So if that means it is halfway over the Atlantic at that point, is there any reason why the drone ship cannot wait for it that far out? Or will such a distant landing never be required due to inherent limitations of the first stage performance?

I'm just trying to ascertain what makes the difference between having to expend a centre core and being  able to recover it on the drone ship. Because the greater the boost the side cores provide, my assumption is the further along the trajectory the centre core is able to travel before returning to earth.