Author Topic: Comprehensive Falcon Family Performance  (Read 14734 times)

Offline sevenperforce

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Comprehensive Falcon Family Performance
« on: 02/20/2018 04:19 PM »
Elon recently let slip on Twitter that flying Falcon Heavy with parallel booster recovery only (expendable core) represents a 10% performance loss over fully-expendable but would only run about $95M. With this figure, and the numbers already published by SpaceX, I was able to put together a pretty comprehensive table of Falcon family performance to virtually any destination. Took a lot of spreadsheet work, but it all came out pretty well.

VehiclePrice (USD)LEO (tanker only)LEO (payload)GTO (2.27km/s)TLI (2.73km/s)LLO (4.04km/s)GEO (4.33km/s)TMI (4.30km/s)
Falcon Heavy (expendable)$150M96.9163.8026.7025.1716.6815.2216.80
Falcon Heavy (recovery x2)$95M87.2257.4224.0322.6515.0113.7015.12
Falcon Heavy (recovery x3)$90M23.5318.118.006.663.653.123.17
Falcon 9 (expendable)$92M24.9922.808.307.744.253.654.02
Falcon 9 (ASDS recovery)$62M17.0413.305.504.502.141.711.75
Falcon 9 (RTLS recovery)<$62M11.749.413.512.700.850.520.56

RTLS performance values were estimated by carefully comparing staging velocities for RTLS missions to staging velocities for ASDS missions; this is likely an underestimate of RTLS capabilities because SpaceX has probably not pushed RTLS to its limits in missions to date.

Falcon Heavy with three-core recovery may also be underestimated for LEO performance, since Falcon Heavy's TWR is so much higher than Falcon 9's, but it should be accurate for BLEO destinations.

LLO and GEO delivery assume extended restart capability for the MVac and do not account for propellant boil-off; this must be adjusted for.

LEO tanker performance assumes that the payload is nothing but an International Docking Adapter (mass: 526 kg), so that it could be docked to a vehicle waiting in LEO for an ejection burn.

ASDS performance above assumes no boostback burn and maximum downrange ASDS position. For ASDS payloads below the maximum payload, SpaceX sends the ASDS only part of the way out and uses the extra margin for a boostback burn to save money and time.

Offline yokem55

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Re: Comprehensive Falcon Family Performance
« Reply #1 on: 02/20/2018 05:00 PM »
That Falcon Heavy 8 MT figure for three core recovery feels like it's been sand bagged a bit. It represents a 70+% loss in performance over fully expendable or expending just the core.

Offline speedevil

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Re: Comprehensive Falcon Family Performance
« Reply #2 on: 02/20/2018 05:09 PM »
That Falcon Heavy 8 MT figure for three core recovery feels like it's been sand bagged a bit. It represents a 70+% loss in performance over fully expendable or expending just the core.

If that is true, the recovery figure to LEO must also be wrong, as it's about right from the rocket equation.

What velocities are being assumed for FH centre core staging - some preliminary work I did on this indicated that you needed quite a lot of propellant remaining in the centre core to get it down to the hottest recovery velocities we've seen.

If we assume 57 tons to LEO recovering two is right, and 18 recovering three is also right, and that we can assume trajectory till BECO is the same, the difference in the centre cores velocity before sep must be the same as the additional second stage velocity required.

57+111+3t,347s->60 = 3571m/s.
?->347s->18+3t = 3571m/s
Gives 59 tons initial stage mass in the second case, 38 tons of fuel, not 111.

111+3+18t, 347s, 59t = 2688m/s.

This seems a very, very implausible number.
I'm probably doing something wrong.
« Last Edit: 02/20/2018 06:11 PM by speedevil »

Offline sevenperforce

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Re: Comprehensive Falcon Family Performance
« Reply #3 on: 02/20/2018 05:40 PM »
That Falcon Heavy 8 MT figure for three core recovery feels like it's been sand bagged a bit. It represents a 70+% loss in performance over fully expendable or expending just the core.
If it's a sandbag, it's not much of one. Three-core recovery requires RTLS on the side boosters and a very long braking burn (either boostback or longer entry burn) on the core, while two-core recovery represents dual ASDS landings for the side boosters but at a generally more benign speed than we've seen with Falcon 9. It's a huge difference.

The quoted payload drop of 10% represents a side-booster staging velocity of 230 m/s lower than if the side boosters were expended. Reserving those 230 m/s of stack dV on the boosters represents a LOT more dV for the naked boosters themselves. In contrast, the amount of propellant the center core needs to brake itself is much higher.

Recall that an expendable Falcon 9 bills at $92M, while a triple-core-recovery FH is $2M cheaper. If triple recovery FH could deliver more payload than an expendable Falcon 9, it would surely cost more.

Offline Nomadd

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Re: Comprehensive Falcon Family Performance
« Reply #4 on: 02/20/2018 07:38 PM »
 I think people might be giving these prices a little too much credibility. How can expended side boosters raise the price $55 million, but an expended core only $5 million?

Offline Semmel

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Re: Comprehensive Falcon Family Performance
« Reply #5 on: 02/20/2018 07:39 PM »
If it's a sandbag, it's not much of one. Three-core recovery requires RTLS on the side boosters and a very long braking burn (either boostback or longer entry burn) on the core, while two-core recovery represents dual ASDS landings for the side boosters but at a generally more benign speed than we've seen with Falcon 9. It's a huge difference.

Hmm, side booster landings on the drone ships should be faster reenty than single stick F9 because the increased T/W ratio makes it go faster (even with throttled centre core). The burn time of the side boosters should be identical, hence the velocity should be higher for FH.

Recall that an expendable Falcon 9 bills at $92M, while a triple-core-recovery FH is $2M cheaper. If triple recovery FH could deliver more payload than an expendable Falcon 9, it would surely cost more.

Not necessarily true. Recovered boosters have value in them selfs. A throw away F9 could cost more than a recoverable FH, even if F9 would throw less than FH.

Online kdhilliard

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Re: Comprehensive Falcon Family Performance
« Reply #6 on: 02/20/2018 07:58 PM »
I think people might be giving these prices a little too much credibility. How can expended side boosters raise the price $55 million, but an expended core only $5 million?

An expended core and twin ASDS recoveries.  Agreed.  However $95 million makes more sense based on Chris G.'s FH reusable price, though I don't understand how he came up with such a precise figure.  From our 2018-02-09 feature article, Falcon Heavy success paves the way for open access to space beyond Earth:
Quote
But perhaps most surprising was a statement made by Mr. Musk the day before Falcon Heavy’s first launch.  During that teleconference, Mr. Musk stated that the overall price for a Falcon Heavy could reduce significantly once Falcon Heavy flies in its fully reusable configuration – essentially lowering its price to just $62 million dollars or the price of a regular, brand new Falcon 9.

Teleconference transcript here
Quote
Well, you know Falcon Heavy is essentially, from a cost standpoint, it's Falcon 9 plus two side boosters. And we expect to recover all three cores, or at least two of the three cores on every flight. Now this is a development flight, so who knows what'll happen on this flight. But being able to reuse those rocket booster cores means that the expendable portion of the Falcon Heavy flight is the same as a Falcon 9 flight. On Falcon 9 we expend the upper stage. We are in the process of recovering the fairing, we're getting better and better at recovering the fairing. So we expect to recover the fairing and the booster, the first stage of Falcon 9. Like I said, only the second stage will be expended. And what's interesting is for Falcon Heavy, it's the same amount that's expended, just the upper stage. So it means we're able to offer heavy, arguably super heavy lift, nearing super heavy lift capability for not much more than the cost of a Falcon 9.

I suspect that the $95 million price was likewise based on high hopes for ease of block 5 reusability.

Offline sevenperforce

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Re: Comprehensive Falcon Family Performance
« Reply #7 on: 02/20/2018 08:28 PM »
I think people might be giving these prices a little too much credibility. How can expended side boosters raise the price $55 million, but an expended core only $5 million?
I try to take everything Elon says with a grain of salt, but pricing information seems like one of those things he wouldn't just make up.

Falcon 9's base price is $62M. Sacrificing the core is a $30M markup, to $92M.

Falcon Heavy's base price is $90M. Sacrificing all three cores is a $30M x 3 markup, to $150M. Tracking so far.

Elon said on Twitter that 2-core recovery "really just costs a little more than expending a Falcon 9", so a $3M markup to $95M. But this would suggest that adding two recoverable boosters would only cost $3M more, in which case we would expect the base price of Falcon Heavy (with triple recovery) to be just $65M.

If it's a sandbag, it's not much of one. Three-core recovery requires RTLS on the side boosters and a very long braking burn (either boostback or longer entry burn) on the core, while two-core recovery represents dual ASDS landings for the side boosters but at a generally more benign speed than we've seen with Falcon 9. It's a huge difference.

Hmm, side booster landings on the drone ships should be faster reenty than single stick F9 because the increased T/W ratio makes it go faster (even with throttled centre core). The burn time of the side boosters should be identical, hence the velocity should be higher for FH.
It depends. Single-stick has to throttle the core down at Max-Q and again as the TWR climbs relatively high, meaning a longer burn time, while the Falcon Heavy can do all the downthrottling with the core and get a more rapid side booster burnout. So the burn time isn't necessarily exactly the same.

Operationally, I do wonder what will give the best performance in a core-expended FH launch. Do they only throttle the core down briefly for Max-Q and gee-loading, and simply cut the side boosters off when their reserves drop to what they need for entry and ASDS landing, or do they throttle the core down gradually throughout the flight to reserve more propellant at side booster MECO?

I suppose the same question applies to a three-core-recovery FH. Even if they burned all the boosters at full throttle from start to finish, they'd need to MECO the side boosters first, to reserve enough propellant for RTLS boostback, while the core could continue to fire for a few seconds. Would this give higher performance than differentially throttling the core?

Not that it matters for number-crunching. I'm sure SpaceX has already determined what the highest performance is, since that's what they are quoting.


Online hkultala

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Re: Comprehensive Falcon Family Performance
« Reply #8 on: 02/20/2018 08:38 PM »
LEO tanker performance assumes that the payload is nothing but an International Docking Adapter (mass: 526 kg), so that it could be docked to a vehicle waiting in LEO for an ejection burn.

umm.. I don't undestand what you mean by this. Fuel remaining in the tank after reaching the orbit with this?


Offline sevenperforce

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Re: Comprehensive Falcon Family Performance
« Reply #9 on: 02/20/2018 08:49 PM »
LEO tanker performance assumes that the payload is nothing but an International Docking Adapter (mass: 526 kg), so that it could be docked to a vehicle waiting in LEO for an ejection burn.

umm.. I don't undestand what you mean by this. Fuel remaining in the tank after reaching the orbit with this?
Right. Elon has talked about orbital propellant transfer, and while this is very unlikely for the Falcon upper stage, I've also seen mission proposals where an empty upper stage is sent into orbit to dock with another vehicle and perform a burn BLEO. So I threw in one column where you'd merely be figuring out how much propellant you'd have left over.

Offline speedevil

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Re: Comprehensive Falcon Family Performance
« Reply #10 on: 02/20/2018 09:01 PM »
Right. Elon has talked about orbital propellant transfer, and while this is very unlikely for the Falcon upper stage, I've also seen mission proposals where an empty upper stage is sent into orbit to dock with another vehicle and perform a burn BLEO. So I threw in one column where you'd merely be figuring out how much propellant you'd have left over.

Does LEO tanker include the fact that it doesn't need a fairing, which must save a fair bit of weight and drag.

I note that the price of FH all recovered + f9 recovered, with F9 launching a payload, and FH launching expendable is the same, and the capability to high energy orbits doing this is also comparable.

Is the 'tanker' mass including or excluding the stage?

Capability with FH expendable as tanker goes up really quite a lot.

I note my 'F9 moon lander' thread. https://forum.nasaspaceflight.com/index.php?topic=45010.0 which goes into some of the sillier possibilities if refuelling works as more than just connecting partially expended stages to your payload.
« Last Edit: 02/20/2018 09:24 PM by speedevil »

Offline sevenperforce

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Re: Comprehensive Falcon Family Performance
« Reply #11 on: 02/20/2018 09:33 PM »
Does LEO tanker include the fact that it doesn't need a fairing, which must save a fair bit of weight and drag.

I note that the price of FH all recovered + f9 recovered, with F9 launching a payload, and FH launching expendable is the same, and the capability to high energy orbits doing this is also comparable.

Is the 'tanker' mass including or excluding the stage?

Capability with FH expendable as tanker goes up really quite a lot.

I note my 'F9 moon lander' thread. https://forum.nasaspaceflight.com/index.php?topic=45010.0
Flying as a tanker (really, flying as a separately-launched BLEO kick stage) would still require SOME kind of cover over the docking adapter, so that their aero model doesn't get weird. Rather than building a completely new fairing, they'd probably just put on a regular clamshell. Other option is to cover it with the nosecone from the Dragon 1.

The "tanker" column lists only the mass of the propellant after orbital insertion, expected in a nominal 185 x 185 km 28.5 degree parking orbit. The true mass will be 4 tonnes more.

Offline speedevil

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Re: Comprehensive Falcon Family Performance
« Reply #12 on: 02/20/2018 09:47 PM »
Rather than building a completely new fairing, they'd probably just put on a regular clamshell. Other option is to cover it with the nosecone from the Dragon 1.

I think I was assuming the booster fairings would fit, but I guess the attachments are rather different, and there is no provision for them to come off.

In principle, the airflow seems not to be a problem, as S2 of course is gone when all the boosters are doing anything aero.
« Last Edit: 02/20/2018 09:54 PM by speedevil »

Offline sevenperforce

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Re: Comprehensive Falcon Family Performance
« Reply #13 on: 02/20/2018 09:57 PM »
Rather than building a completely new fairing, they'd probably just put on a regular clamshell. Other option is to cover it with the nosecone from the Dragon 1.

I think I was assuming the booster fairings would fit, but I guess the attachments are rather different, and there is no provision for them to come off.

In principle, the airflow seems not to be a problem, as S2 of course is gone when all the boosters are doing anything aero.
Yes, I was thinking standard booster fairings. The IDA can fit in the trunk of a Dragon 1 so surely it can be bolted to the PAF under a standard recoverable fairing.

Airflow for boosters is all backwards, so that's a little different.

Online hkultala

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Re: Comprehensive Falcon Family Performance
« Reply #14 on: 02/20/2018 10:08 PM »
LEO tanker performance assumes that the payload is nothing but an International Docking Adapter (mass: 526 kg), so that it could be docked to a vehicle waiting in LEO for an ejection burn.

umm.. I don't undestand what you mean by this. Fuel remaining in the tank after reaching the orbit with this?
Right. Elon has talked about orbital propellant transfer, and while this is very unlikely for the Falcon upper stage, I've also seen mission proposals where an empty upper stage is sent into orbit to dock with another vehicle and perform a burn BLEO. So I threw in one column where you'd merely be figuring out how much propellant you'd have left over.

Then those numbers look like they have something badly wrong.

first, the principle. We know that the second stage is undersized for FH. It would make sense to spend MORE fuel for 2nd stage burn, not less.


Then some calculations:

Expendable FH:

F9/FH second stage + your adapter is ~4.5 tonnes, and has about 107500 tonnes of propellant.

With 97 tonnes of fuel remaining, this means that the second stage would give it only ~328 m/s of delta-v.

So the core would need to go to almost orbital velocity (with a 112-tonne 2nd stage as a payload)


FH with reusable side boosters:

With 87 tonnes of fuel remaining, this means that the second stage would give it only about 673 m/s of delta-v

And with your reusable side boosters, the core would have to reach ~6.8km/s of staging velocity (in addition to the gravity losses).


These don't seem like reasonable staging velocities, no way the boosters and core are capable of this.



« Last Edit: 02/21/2018 07:51 AM by hkultala »

Offline Nomadd

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Re: Comprehensive Falcon Family Performance
« Reply #15 on: 02/20/2018 10:43 PM »

Falcon Heavy's base price is $90M. Sacrificing all three cores is a $30M x 3 markup, to $150M. Tracking so far.

That's some interesting math there.

Online hkultala

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Re: Comprehensive Falcon Family Performance
« Reply #16 on: 02/21/2018 08:26 AM »
Numbers for fully recoverable FH seem to be considerably lower in this than the NASA database.

(which itself probably has too low numbers, based on old FH model)
« Last Edit: 02/21/2018 09:31 AM by hkultala »

Offline guckyfan

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Re: Comprehensive Falcon Family Performance
« Reply #17 on: 02/21/2018 08:27 AM »
Falcon Heavy (recovery x3)   3.17t to TMI

3.17t to TMI seems way low. When Red Dragon was still on Elon once mentioned that they may be able to send it off to Mars while recovering all 3 cores. Though that was maybe not likely the performance needs to be a lot closer to 10t to even consider it.

Online MATTBLAK

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Re: Comprehensive Falcon Family Performance
« Reply #18 on: 02/21/2018 08:51 AM »
The mass of the empty second stage and engine, plus the payload adaptor and Tesla should bring us closer to the answer.
« Last Edit: 02/21/2018 11:36 AM by MATTBLAK »
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Online hkultala

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Re: Comprehensive Falcon Family Performance
« Reply #19 on: 02/21/2018 09:27 AM »
Elon recently let slip on Twitter that flying Falcon Heavy with parallel booster recovery only (expendable core) represents a 10% performance loss over fully-expendable but would only run about $95M.

When he said it, he obviously meant it's about 10% performance loss is to SOME orbit. (probably LEO maximum payload).

For other orbits, the difference is different, and probably much greater for high energy trajectories.

And he may even have meant barge landing instead of RTLS of the side boosters in this number. (construction/buying another barge to atlantic was just announced)




This payload table is simply FULL or errors, inconsistent numbers based on incorrect assumptions.

« Last Edit: 02/21/2018 09:37 AM by hkultala »

Offline IRobot

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Re: Comprehensive Falcon Family Performance
« Reply #20 on: 02/21/2018 10:10 AM »
VehiclePrice (USD)LEO (tanker only)LEO (payload)GTO (2.27km/s)TLI (2.73km/s)LLO (4.04km/s)GEO (4.33km/s)TMI (4.30km/s)
Falcon Heavy (recovery x3)$90M23.5318.118.006.663.653.123.17
Falcon 9 (expendable)$92M24.9922.808.307.744.253.654.02




If the numbers are correct, then FH 3x recovery makes no sense, as you can fly an expendable F9 with less risks.

Edit: could only make sense for a central core recovery for inspection, but not for all flights.
« Last Edit: 02/21/2018 10:12 AM by IRobot »

Offline speedevil

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Re: Comprehensive Falcon Family Performance
« Reply #21 on: 02/21/2018 10:13 AM »
When he said it, he obviously meant it's about 10% performance loss is to SOME orbit. (probably LEO maximum payload).

For other orbits, the difference is different, and probably much greater for high energy trajectories.

And he may even have meant barge landing instead of RTLS of the side boosters in this number. (construction/buying another barge to atlantic was just announced)




This payload table is simply FULL or errors, inconsistent numbers based on incorrect assumptions.

The spreadsheet - or at least more of the methodology needs spelled out.

I did rough numbers, and if you assume that the '10% less' number originates from a lower velocity at MECO, at least at LEO and GEO, the loss is about the same for the first stage velocity, at around 250m/s.

Offline sevenperforce

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Re: Comprehensive Falcon Family Performance
« Reply #22 on: 02/21/2018 11:50 AM »

Falcon Heavy's base price is $90M. Sacrificing all three cores is a $30M x 3 markup, to $150M. Tracking so far.

That's some interesting math there.
Wow, I'm an idiot.

So basically SpaceX's pricing is not actually straightforward.
« Last Edit: 02/21/2018 12:19 PM by sevenperforce »

Offline sevenperforce

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Re: Comprehensive Falcon Family Performance
« Reply #23 on: 02/21/2018 12:19 PM »
Elon has talked about orbital propellant transfer, and while this is very unlikely for the Falcon upper stage, I've also seen mission proposals where an empty upper stage is sent into orbit to dock with another vehicle and perform a burn BLEO. So I threw in one column where you'd merely be figuring out how much propellant you'd have left over.

Then those numbers look like they have something badly wrong.

first, the principle. We know that the second stage is undersized for FH. It would make sense to spend MORE fuel for 2nd stage burn, not less.


Then some calculations:

Expendable FH:

F9/FH second stage + your adapter is ~4.5 tonnes, and has about 107500 tonnes of propellant.

With 97 tonnes of fuel remaining, this means that the second stage would give it only ~328 m/s of delta-v.

So the core would need to go to almost orbital velocity (with a 112-tonne 2nd stage as a payload)
Well, let's start with a benchmark that we know. FH expendable is advertised at 3.5 tonnes to Pluto, which requires around 8.2 km/s beyond LEO. A Falcon upper stage masses 4 tonnes and carries 107.5 tonnes of propellant, so m0/m1 = 15.33. At an isp of 345 seconds, that means the upper stage packs a total of 9.23 km/s.

If SpaceX's figure is to be believed, then, staging for an expendable max-payload Pluto mission occurs at LEO-1.03 km/s, or an absolute staging velocity of 6.77 km/s. If that 3.5-tonne Pluto payload was swapped out for a half-tonne IDA, then the upper stage would still have 78.1 tonnes of propellant remaining at orbital insertion.

Of course, the core is lifting slightly less mass with the IDA in place of the Pluto package, so we should expect slightly more velocity at staging, meaning more propellant remaining at SECO. The core throttledown profile is probably going to be tuned to each mission and payload, so estimating how the side boosters factor in will be difficult.

Quote
FH with reusable side boosters:

With 87 tonnes of fuel remaining, this means that the second stage would give it only about 673 m/s of delta-v

And with your reusable side boosters, the core would have to reach ~6.8km/s of staging velocity (in addition to the gravity losses).

These don't seem like reasonable staging velocities, no way the boosters and core are capable of this.
Well, 6.77 km/s would already be achieved in an expendable flight with a payload of 3.5 tonnes. With an even lower payload, you could likely reach a higher staging velocity and still have enough propellant for booster recovery.

Offline Mader Levap

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Re: Comprehensive Falcon Family Performance
« Reply #24 on: 02/21/2018 12:25 PM »
This whole mess does not add up for very simple reason: those are prices for customer, not cost for SpaceX.

Things like "FH with middle core expended costs only 5 mln $ more" show it is fools' errand to try "what is true cost" kremlinology based on price alone. SpaceX can and will set up prices so certain behaviours are incentivized and other penalized. For example, they want reward customers for using FH fully reusable over F9 expendable.
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Offline sevenperforce

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Re: Comprehensive Falcon Family Performance
« Reply #25 on: 02/21/2018 12:35 PM »
Numbers for fully recoverable FH seem to be considerably lower in this than the NASA database.

(which itself probably has too low numbers, based on old FH model)
Numbers for fully-recoverable FH are based on the advertised limit of 8 tonnes to GTO.

Elon recently let slip on Twitter that flying Falcon Heavy with parallel booster recovery only (expendable core) represents a 10% performance loss over fully-expendable but would only run about $95M.

When he said it, he obviously meant it's about 10% performance loss is to SOME orbit. (probably LEO maximum payload).

For other orbits, the difference is different, and probably much greater for high energy trajectories.

And he may even have meant barge landing instead of RTLS of the side boosters in this number. (construction/buying another barge to atlantic was just announced)
Yes, that's precisely what was meant, and that's what I worked from.

He may have meant 10% performance loss to LEO, or he may have meant 10% performance loss to GTO. We don't know. That's why I said that those particular numbers are less certain.

If the numbers are correct, then FH 3x recovery makes no sense, as you can fly an expendable F9 with less risks.

Edit: could only make sense for a central core recovery for inspection, but not for all flights.
But a Falcon Heavy with three-core recovery is cheaper.

The numbers surprised me, too, but they're spelled out pretty clearly. The SpaceX pricing page says that Falcon 9 is available at the base price for up to 5.5 tonnes to GTO, but can deliver up to 8.03 tonnes to GTO expendable. It says that FH is available at the base price for up to 8 tonnes to GTO, but can deliver up to 26.7 tonnes to GTO expendable.

This whole mess does not add up for very simple reason: those are prices for customer, not cost for SpaceX.

Things like "FH with middle core expended costs only 5 mln $ more" show it is fools' errand to try "what is true cost" kremlinology based on price alone. SpaceX can and will set up prices so certain behaviours are incentivized and other penalized. For example, they want reward customers for using FH fully reusable over F9 expendable.
Yeah, you're right. Hence pricing FHxR3 lower than F9E.

Online hkultala

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Re: Comprehensive Falcon Family Performance
« Reply #26 on: 02/21/2018 01:18 PM »
Numbers for fully recoverable FH seem to be considerably lower in this than the NASA database.

(which itself probably has too low numbers, based on old FH model)
Numbers for fully-recoverable FH are based on the advertised limit of 8 tonnes to GTO.

Advertized limit for $90 million price tag. Not advertised limit of fully reusable.

The price point has been put up to the web page 5.5.2016. Back then they had no operational block 5 engines, and the number is probably based on block 3 engines, not block 5 engines.

5.5.2016 (and much later also) the maximum payload of FH was listed as 55400 kg. As the maximum payload has increased by 15% since, probably also the reusable payload has increased by about similar amount (but probably even more, as there have been also other advances that help especially reusable payload, like 3-engine landing burn, and the better T/W also helps reusable payload more, as the side boosters run out of fuel faster, after moving shorter horizontal distance, so less flyback distance).

So now they have updated their maximum payload number for block 5 engines, but their pricing number is still based on the block 3 reusable payload.

So, if you want to base your FH GTO performance on the FH adverticed pricing numbers, use at least 9.2 tonnes to GTO instead.
« Last Edit: 02/21/2018 01:26 PM by hkultala »

Offline sevenperforce

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Re: Comprehensive Falcon Family Performance
« Reply #27 on: 02/21/2018 01:30 PM »
The spreadsheet - or at least more of the methodology needs spelled out.

I did rough numbers, and if you assume that the '10% less' number originates from a lower velocity at MECO, at least at LEO and GEO, the loss is about the same for the first stage velocity, at around 250m/s.
The methodology was fairly straightforward. If you take the advertised payloads for Falcon Heavy expendable, you can trivially determine the total dV on the upper stage at staging for each given payload. For example, a 3.5-tonne payload (to Pluto) packs 9.23 km/s, a 16.8-tonne payload (to Mars) packs 6.15 km/s, and a 26.7-tonne payload (to GTO) packs 5.09 km/s. We also know the excess residual dV each stage has; transfer to Pluto costs 8.2 km/s, transfer to Mars costs 4.3 km/s, and GTO costs 2.27 km/s.

If you plot the total stage dV against the excess residual dV, you get a perfectly straight line. The line crosses the y-axis at 3.212 km/s total dV, 0 km/s excess residual dV...and sure enough, you get 3.2 km/s of total dV when the upper stage has 63.8 tonnes of payload, corresponding to the maximum advertised LEO payload.

This allows you to estimate residual dV for any possible payload...or, inversely, the maximum payload for any given destination. It should be quite accurate for any payloads between 64 tonnes and 3.5 tonnes, though extrapolating out to payloads under 3 tonnes may be a bad idea since the curve should start to curve toward an absolute ceiling.

The same method was used to determine the payloads for Falcon 9 expendable.

For ASDS recovery (and for 3-core recovery), I determined what gap in staging velocity would yield the advertised payload drop. For example, we know that ASDS recovery tops out at 5.5 tonnes to GTO. From the expendable Falcon 9 performance curve, a 5.5-tonne payload would have 3.52 km/s of residual dV, 1.25 km/s more than needed for GTO. So we can estimate that an ASDS recovery F9 would need to stage 1.25 km/s slower than an expendable F9, and I calculated the performance curve for F9 ASDS accordingly.

Numbers for fully recoverable FH seem to be considerably lower in this than the NASA database.

(which itself probably has too low numbers, based on old FH model)
Numbers for fully-recoverable FH are based on the advertised limit of 8 tonnes to GTO.

Advertized limit for $90 million price tag. Not advertised limit of fully reusable.
Well, Elon said that two-core recovery is $95M and expendable is $150M, so the only other option is three-core recovery.

Quote
The price point has been put up to the web page 5.5.2016. Back then they had no operational block 5 engines, and the number is probably based on block 3 engines, not block 5 engines.

5.5.2016 (and much later also) the maximum payload of FH was listed as 55400 kg. As the maximum payload has increased by 15% since, probably also the reusable payload has increased by about similar amount (but probably even more, as there have been also other advances that help especially reusable payload, like 3-engine landing burn, and the better T/W also helps reusable payload more, as the side boosters run out of fuel faster, after moving shorter horizontal distance, so less flyback distance).

So now they have updated their maximum payload number for block 5 engines, but their pricing number is still based on the block 3 reusable payload.

So, if you want to base your FH GTO performance on the FH adverticed pricing numbers, use at least 9.2 tonnes to GTO instead.
I can certainly accept that the FHRx3 payload to GTO has increased, but what's the basis for the 9.2-tonne number?

Offline envy887

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Re: Comprehensive Falcon Family Performance
« Reply #28 on: 02/21/2018 01:51 PM »
NASA LSP updated didn't update the numbers for FH in the last couple weeks, but they still don't match SpaceX's website. I wonder if SpaceX is assuming MRS and LSP is applying some margins?
« Last Edit: 02/21/2018 04:00 PM by envy887 »

Offline ugordan

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Re: Comprehensive Falcon Family Performance
« Reply #29 on: 02/21/2018 01:55 PM »
NASA LSP updated the numbers for FH in the last couple weeks

They don't look updated to me and those two graphs look identical to me?

Online hkultala

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Re: Comprehensive Falcon Family Performance
« Reply #30 on: 02/21/2018 02:14 PM »
Numbers for fully recoverable FH seem to be considerably lower in this than the NASA database.

(which itself probably has too low numbers, based on old FH model)
Numbers for fully-recoverable FH are based on the advertised limit of 8 tonnes to GTO.

Advertized limit for $90 million price tag. Not advertised limit of fully reusable.
Well, Elon said that two-core recovery is $95M and expendable is $150M, so the only other option is three-core recovery.

Yes, but for OLD version of FH and maybe with some extra margins for just to be sure they can reach it if some problems would arrive. (either development problems or accident-like problems)

For example, a margin to be able to lose one engine from a side booster and still be able to do everything like planned.

Quote
Quote
The price point has been put up to the web page 5.5.2016. Back then they had no operational block 5 engines, and the number is probably based on block 3 engines, not block 5 engines.

5.5.2016 (and much later also) the maximum payload of FH was listed as 55400 kg. As the maximum payload has increased by 15% since, probably also the reusable payload has increased by about similar amount (but probably even more, as there have been also other advances that help especially reusable payload, like 3-engine landing burn, and the better T/W also helps reusable payload more, as the side boosters run out of fuel faster, after moving shorter horizontal distance, so less flyback distance).

So now they have updated their maximum payload number for block 5 engines, but their pricing number is still based on the block 3 reusable payload.

So, if you want to base your FH GTO performance on the FH adverticed pricing numbers, use at least 9.2 tonnes to GTO instead.
I can certainly accept that the FHRx3 payload to GTO has increased, but what's the basis for the 9.2-tonne number?

Linear extrapolation from the maximum LEO payload increase between 5.5.2016(block 3) and current (block 5)

63.8 / 54.4   = 1.15
1.15 * 8 = 9.2

Extrapolation from expendable GTO capacities gives even bigger increase

26.7 /22.2 = 1.20
1.20 * 8 = 9.6

And extrapolation from expendable TMI capacities even more.

16.8 / 13.6 = 1.235

1.235 * 8 = 9.9


The payload size and stage2 delta-v for 3-S1 recoverable is closest to the TMI of the expendable, so from these 3 numbers we should use that as our basis.

So actually the payload of FHR to GTO should be in the range of ~10 tonnes. (if the original 8 tonnes was to full capacity of block 3)
« Last Edit: 02/21/2018 02:30 PM by hkultala »

Offline IRobot

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Re: Comprehensive Falcon Family Performance
« Reply #31 on: 02/21/2018 03:49 PM »
If the numbers are correct, then FH 3x recovery makes no sense, as you can fly an expendable F9 with less risks.

Edit: could only make sense for a central core recovery for inspection, but not for all flights.
But a Falcon Heavy with three-core recovery is cheaper.
They are very similar prices, so an expendable F9 has less risk and no recovery costs.

Offline envy887

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Re: Comprehensive Falcon Family Performance
« Reply #32 on: 02/21/2018 03:55 PM »
NASA LSP updated the numbers for FH in the last couple weeks

They don't look updated to me and those two graphs look identical to me?

Whoops. I was reading the c3=12 line on one and the c3=0 line on the other. They are the same.

Offline envy887

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Re: Comprehensive Falcon Family Performance
« Reply #33 on: 02/21/2018 04:00 PM »
If the numbers are correct, then FH 3x recovery makes no sense, as you can fly an expendable F9 with less risks.

Edit: could only make sense for a central core recovery for inspection, but not for all flights.
But a Falcon Heavy with three-core recovery is cheaper.
They are very similar prices, so an expendable F9 has less risk and no recovery costs.

Price isn't everything. If the lead time for an expendable F9 is 6 months longer because of a slower production rate, and your satellite earns $20M per month, then you just lost $122 million.

IMO those prices won't be similar for long, as SpaceX can probably make about three times as much profit on a FHR as on F9E.

Offline sevenperforce

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Re: Comprehensive Falcon Family Performance
« Reply #34 on: 02/21/2018 04:21 PM »
I can certainly accept that the FHRx3 payload to GTO has increased, but what's the basis for the 9.2-tonne number?

Linear extrapolation from the maximum LEO payload increase between 5.5.2016(block 3) and current (block 5)

63.8 / 54.4   = 1.15
1.15 * 8 = 9.2

Extrapolation from expendable GTO capacities gives even bigger increase

26.7 /22.2 = 1.20
1.20 * 8 = 9.6

And extrapolation from expendable TMI capacities even more.

16.8 / 13.6 = 1.235

1.235 * 8 = 9.9


The payload size and stage2 delta-v for 3-S1 recoverable is closest to the TMI of the expendable, so from these 3 numbers we should use that as our basis.

So actually the payload of FHR to GTO should be in the range of ~10 tonnes. (if the original 8 tonnes was to full capacity of block 3)
Interesting. Originally, I had tried to calculate F9's ASDS performance based on the observed MECO velocities, and came up with a much higher number than 5.5 tonnes. Do you know if the F9 reusable performance has gone up as well?

I'm not sure if linear extrapolation is the best approach, especially since LEO and BLEO capabilities are going to be wildly divergent since kerolox is low-isp, high-thrust.

Here's an approach that might be a little more promising. A 54.4-tonne payload on the 4-tonne upper stage would have 3530 m/s of dV on the upper stage. In contrast, a 63.8-tonne payload would have 3212 m/s of dV. Since neither the MVac isp nor the propellant load on the upper stage has changed from Block 3 to Block 5, this means Block 5 FHe must stage 318 m/s higher than Block 3 FHe to improve the payload capability by this much.

How does this equate to FHR3? Well, a higher staging velocity means more propellant needs to be reserved on the core for a longer boostback or entry burn, but improvements in landing burns and glide ratio have probably counterbalanced this. So if Block 3 FHR could do 8 tonnes to GTO, Block 5 FHR would be able to send an 8-tonne payload to GTO with 318 m/s of dV left in the tank.

Modifying my payload predictor curve to meet this performance (specifically, 8 tonnes to LEO+2.588 km/s) brings us to a Falcon Heavy capability of 21.2 tonnes to LEO, 9.44 tonnes to GTO, 3.94 tonnes to Mars, 7.9 tonnes to the moon, 3.88 tonnes direct to GEO, 4.49 tonnes to lunar orbit, and 27.6 tonnes of residuals when flown to LEO with only an IDA.

Offline sevenperforce

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Re: Comprehensive Falcon Family Performance
« Reply #35 on: 02/21/2018 04:42 PM »
For reference, if you do the same math with the other performance increases, you're looking at a 423 m/s staging velocity increase for the GTO-class payloads on FH expendable, and a 480 m/s staging velocity increase for the TMI-class payloads on FH expendable. However, the tyranny of the rocket equation says that if you're staging much earlier for FHR3, you're not going to see quite as much of a jump, so sticking with those lower figures is probably a safe bet.

That's interesting. FHR3 outperforms F9E for all payloads except TMI and LEO.

Offline intrepidpursuit

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Re: Comprehensive Falcon Family Performance
« Reply #36 on: 02/22/2018 06:49 PM »
I think people might be giving these prices a little too much credibility. How can expended side boosters raise the price $55 million, but an expended core only $5 million?

I posted about this in great detail in in this thread. Essentially, it all makes sense if you subscribe the premise that SpaceX make way more margin on recovered flights than expendable. There is no pressure on them to go lower in price right now and they have a big investment to pay off. So keep the expendable flights sustainable, but make bank to pay for BFR on recovery.

As long as it is cheaper to use a fully reusable FH than an expendable F9 and no one is making payloads that require an expendable FH, they make a huge margin while being the cheapest and most capable provider in the industry.

Offline envy887

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Re: Comprehensive Falcon Family Performance
« Reply #37 on: 02/23/2018 03:16 AM »
I think people might be giving these prices a little too much credibility. How can expended side boosters raise the price $55 million, but an expended core only $5 million?

SpaceX can charge whatever price they want. An expended F9 could be $6 billion per flight and reused FH 3 for a nickel. Who says it has to make sense?

Offline Stan-1967

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Re: Comprehensive Falcon Family Performance
« Reply #38 on: 02/23/2018 03:33 AM »
I think people might be giving these prices a little too much credibility. How can expended side boosters raise the price $55 million, but an expended core only $5 million?

SpaceX likely has different amortization rates for side boosters vs. the center core.  The price for FH probably assumes just a few re-uses of the core, and perhaps only a single use for the average FH mission.  Block 5 side cores are supposed to give 10 re-uses without refurbishment, so if you prematurely expend an asset that is supposed to be on your books generating revenue, you would want to recover that cost & revenue if they were going to be expended. 

The condition of re-used side cores is a place where buying launches from SpaceX is going to more analogous to going to a used car lot.  They will, by necessity, assert that all previous flown boosters are the same.  However behind the scenes, they will know which are aging rapidly, and which ones are true cherries.  This will leave plenty negotiating room to whittle away at that $55M premium to expend the side cores if it makes the difference in winning a launch.

Offline Nomadd

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Re: Comprehensive Falcon Family Performance
« Reply #39 on: 02/24/2018 07:23 AM »
I think people might be giving these prices a little too much credibility. How can expended side boosters raise the price $55 million, but an expended core only $5 million?

SpaceX can charge whatever price they want. An expended F9 could be $6 billion per flight and reused FH 3 for a nickel. Who says it has to make sense?
The people who pay the bill.

Offline envy887

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Re: Comprehensive Falcon Family Performance
« Reply #40 on: 02/25/2018 12:12 AM »
I think people might be giving these prices a little too much credibility. How can expended side boosters raise the price $55 million, but an expended core only $5 million?

SpaceX can charge whatever price they want. An expended F9 could be $6 billion per flight and reused FH 3 for a nickel. Who says it has to make sense?
The people who pay the bill.

Who won't be complaining if SpaceX offers almost triple the performance for only $5 million more.

Offline speedevil

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Re: Comprehensive Falcon Family Performance
« Reply #41 on: 05/11/2018 11:04 AM »
From the transcript of the post-launch conference of the first block 5 launch by internetftw

Quote
Musk: The Merlin engines, the engine thrust is going to increase by approximately 8%, to 190,000 pounds of thrust at sea level. We think there's probably a little more room there, maybe going up to 10% or so.

A quick estimate approximates full thrust expendable performance at 18650kg or so, out of Canaveral to 180km.
This is low, but at least in the order of magnitude.

Increasing the liftoff thrust from 7000kN to 7560kN and the second stage by the mentioned 5% takes this to 19180kg, or 3% increase.
Adding that extra couple of percent only bumps it by a hundred kg.

This would presumably help lots more on expendable core FH launches.

Offline envy887

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Re: Comprehensive Falcon Family Performance
« Reply #42 on: 05/11/2018 12:42 PM »
From the transcript of the post-launch conference of the first block 5 launch by internetftw

Quote
Musk: The Merlin engines, the engine thrust is going to increase by approximately 8%, to 190,000 pounds of thrust at sea level. We think there's probably a little more room there, maybe going up to 10% or so.

A quick estimate approximates full thrust expendable performance at 18650kg or so, out of Canaveral to 180km.
This is low, but at least in the order of magnitude.

Increasing the liftoff thrust from 7000kN to 7560kN and the second stage by the mentioned 5% takes this to 19180kg, or 3% increase.
Adding that extra couple of percent only bumps it by a hundred kg.

This would presumably help lots more on expendable core FH launches.

It probably helps more on RTLS launches; the faster it can accelerate to staging and turn around, the less distance it has to cover on the return leg.

Online OnWithTheShow

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Re: Comprehensive Falcon Family Performance
« Reply #43 on: 05/11/2018 01:26 PM »
Also we do not know how much mass the Block 5 improvements added to the rocket. So there may not actually be any performance improvements especially when we hear about composite structures being replaced with titanium and active water cooling.

Offline speedevil

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Re: Comprehensive Falcon Family Performance
« Reply #44 on: 05/12/2018 11:48 AM »
Considering only SpaceX costs.
Quote
a marginal cost for a Falcon 9 launch down, fully considered, down under five or six million dollars.
Quote
we intend to demonstrate two orbital launches of the same Block 5 vehicle within 24 hours no later than next year.

Or, in principle, eight launches in one day over four sites.
Neglecting rather a lot, and assuming they tried for on-orbit fuel transfer, a full S2 can throw ten tons clear to jupiter on a direct trajectory, or thirty tons to Mars.

For a cost to SpaceX of around the revenue of a couple of regular launches.

Offline speedevil

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Re: Comprehensive Falcon Family Performance
« Reply #45 on: 10/03/2018 10:09 AM »
Elon recently let slip on Twitter that flying Falcon Heavy with parallel booster recovery only (expendable core) represents a 10% performance loss over fully-expendable but would only run about $95M. With this figure, and the numbers already published by SpaceX, I was able to put together a pretty comprehensive table of Falcon family performance to virtually any destination. Took a lot of spreadsheet work, but it all came out pretty well.

VehiclePrice (USD)LEO (tanker only)LEO (payload)GTO (2.27km/s)GTO2.45realTLI (2.73km/s)LLO (4.04km/s)GEO (4.33km/s)TMI (4.30km/s)
Falcon Heavy (expendable)$150M96.9163.8026.7015+25.1716.6815.2216.80
Falcon Heavy (recovery x2)$95M87.2257.4224.0313.5+???22.6515.0113.7015.12
Falcon Heavy (recovery x3)$90M23.5318.118.00106.663.653.123.17
Falcon 9 (expendable)$92M24.9922.808.306.57.744.253.654.02
Falcon 9 (ASDS recovery)$62M17.0413.305.505.54.502.141.711.75
Falcon 9 (RTLS recovery)<$62M11.749.413.513.52.700.850.520.56
I note the recent tweet.
From a slide in a presentation by Hans.
As shown on twitter

I have added a column in the table '2.45real' - this is the claimed payload to 2.45km/s, not the 2.27 used above.

The estimated and real payloads are identical for F9 reusable, though to a higher energy orbit - actual full fat GTO, GEO-1800.

F9 expendable is a little lower - is it possible that the recoveries are now using less propellant than thought, and that's where the margin to go all the way to GTO is coming from?
The margin between 5.5 and 6.5 at GTO is about 320m/s.
If this is coming from the first stage, this implies only 13 tons of propellant or so remaining in the first stage to do everything, and that is really impressive if true. (~1800m/s total delta-v to do entry and landing burns)
Later tweets pointed me to the fact that spacexs website quotes 8.5 to GTO, so something funky is going on.

A payload for only two recoveries was not given, so I estimated using the '90% of expendable' quote from Elon about FH payload in two recovery mode.
FH recovery with all three cores to droneships gets an impressive 10 tons.
« Last Edit: 10/03/2018 10:20 AM by speedevil »

Offline envy887

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Re: Comprehensive Falcon Family Performance
« Reply #46 on: 10/03/2018 12:32 PM »
Elon recently let slip on Twitter that flying Falcon Heavy with parallel booster recovery only (expendable core) represents a 10% performance loss over fully-expendable but would only run about $95M. With this figure, and the numbers already published by SpaceX, I was able to put together a pretty comprehensive table of Falcon family performance to virtually any destination. Took a lot of spreadsheet work, but it all came out pretty well.

VehiclePrice (USD)LEO (tanker only)LEO (payload)GTO (2.27km/s)GTO2.45realTLI (2.73km/s)LLO (4.04km/s)GEO (4.33km/s)TMI (4.30km/s)
Falcon Heavy (expendable)$150M96.9163.8026.7015+25.1716.6815.2216.80
Falcon Heavy (recovery x2)$95M87.2257.4224.0313.5+???22.6515.0113.7015.12
Falcon Heavy (recovery x3)$90M23.5318.118.00106.663.653.123.17
Falcon 9 (expendable)$92M24.9922.808.306.57.744.253.654.02
Falcon 9 (ASDS recovery)$62M17.0413.305.505.54.502.141.711.75
Falcon 9 (RTLS recovery)<$62M11.749.413.513.52.700.850.520.56
I note the recent tweet.
From a slide in a presentation by Hans.
As shown on twitter

I have added a column in the table '2.45real' - this is the claimed payload to 2.45km/s, not the 2.27 used above.

The estimated and real payloads are identical for F9 reusable, though to a higher energy orbit - actual full fat GTO, GEO-1800.

F9 expendable is a little lower - is it possible that the recoveries are now using less propellant than thought, and that's where the margin to go all the way to GTO is coming from?
The margin between 5.5 and 6.5 at GTO is about 320m/s.
If this is coming from the first stage, this implies only 13 tons of propellant or so remaining in the first stage to do everything, and that is really impressive if true. (~1800m/s total delta-v to do entry and landing burns)
Later tweets pointed me to the fact that spacexs website quotes 8.5 to GTO, so something funky is going on.

A payload for only two recoveries was not given, so I estimated using the '90% of expendable' quote from Elon about FH payload in two recovery mode.
FH recovery with all three cores to droneships gets an impressive 10 tons.

Hans is sandbagging heavily. A previous block of F9 lifted the 6761 kg Intelsat 35e to 25.85° x 42742km x 296km, which is a considerably higher energy orbit than the one Hans listed. F9 B5 expended performance is definitely way more than 6500 kg.

Also, 5500 kg to both 2.27 km/s and 2.45 km/s? That doesn't even make sense.

Offline speedevil

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Re: Comprehensive Falcon Family Performance
« Reply #47 on: 10/03/2018 12:38 PM »
Elon recently let slip on Twitter that flying Falcon Heavy with parallel booster recovery only (expendable core) represents a 10% performance loss over fully-expendable but would only run about $95M. With this figure, and the numbers already published by SpaceX, I was able to put together a pretty comprehensive table of Falcon family performance to virtually any destination. Took a lot of spreadsheet work, but it all came out pretty well.

VehiclePrice (USD)LEO (tanker only)LEO (payload)GTO (2.27km/s)GTO2.45realTLI (2.73km/s)LLO (4.04km/s)GEO (4.33km/s)TMI (4.30km/s)
Falcon Heavy (expendable)$150M96.9163.8026.7015+25.1716.6815.2216.80
Falcon Heavy (recovery x2)$95M87.2257.4224.0313.5+???22.6515.0113.7015.12
Falcon Heavy (recovery x3)$90M23.5318.118.00106.663.653.123.17
Falcon 9 (expendable)$92M24.9922.808.306.57.744.253.654.02
Falcon 9 (ASDS recovery)$62M17.0413.305.505.54.502.141.711.75
Falcon 9 (RTLS recovery)<$62M11.749.413.513.52.700.850.520.56
I note the recent tweet.
From a slide in a presentation by Hans.
As shown on twitter

I have added a column in the table '2.45real' - this is the claimed payload to 2.45km/s, not the 2.27 used above.

The estimated and real payloads are identical for F9 reusable, though to a higher energy orbit - actual full fat GTO, GEO-1800.

F9 expendable is a little lower - is it possible that the recoveries are now using less propellant than thought, and that's where the margin to go all the way to GTO is coming from?
The margin between 5.5 and 6.5 at GTO is about 320m/s.
If this is coming from the first stage, this implies only 13 tons of propellant or so remaining in the first stage to do everything, and that is really impressive if true. (~1800m/s total delta-v to do entry and landing burns)
Later tweets pointed me to the fact that spacexs website quotes 8.5 to GTO, so something funky is going on.

A payload for only two recoveries was not given, so I estimated using the '90% of expendable' quote from Elon about FH payload in two recovery mode.
FH recovery with all three cores to droneships gets an impressive 10 tons.

Hans is sandbagging heavily. A previous block of F9 lifted the 6761 kg Intelsat 35e to 25.85° x 42742km x 296km, which is a considerably higher energy orbit than the one Hans listed. F9 B5 expended performance is definitely way more than 6500 kg.

Also, 5500 kg to both 2.27 km/s and 2.45 km/s? That doesn't even make sense.

5500kg is perhaps an older number, to 2.27, than the 2.45 one.

I agree there seem to be several inconsistencies.

Offline envy887

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Re: Comprehensive Falcon Family Performance
« Reply #48 on: 10/03/2018 12:50 PM »
5500kg is perhaps an older number, to 2.27, than the 2.45 one.

I agree there seem to be several inconsistencies.

All the listed numbers should be to GEO-1800 which is LEO+2500, or about 185 x 35786 x 27 degrees. SpaceX does not advertise GTO reference payloads to anything other than GEO-1800.

Hans also said "we've actually flown a little bit more than that" about the 6500 kg, while discussing this slide, see the video posted to the SpaceX talks thread. It's definitely not the max capability.

Online GWH

Re: Comprehensive Falcon Family Performance
« Reply #49 on: 10/04/2018 12:36 AM »
The slide that shows these GTO numbers also uses old graphics of F9 & FH - the giveaway is the longer side cores on FH.

Stating all 3 cores to droneships seems odd, last I heard only 2 East coast drone ships were planned. Center expendable and side cores to drone ships would seem a more logical point to make than simply "expendable" since the performance penalty is (reportedly) minimal.

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