Author Topic: Comprehensive Falcon Family Performance  (Read 14204 times)

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.

Online 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.

Offline 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.

Online 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.

Online 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.

Online 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.

Offline 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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