Hypothetical new Falcon 1 type LV

[RoboGoofers]

I could see spacex "selling" end-of-life merlins to a subsidiary that would repackage them into expendable low cost launchers. customers would trade reliability for dirt-cheap orbital access. it would be a huge boon for universities and startups.

Such a subsidiary would also be a great "minor leagues" for spacex to train up talent.

[Hauerg]

OK, speeking of "free" or dirt cheap engines: What could a 3 core F1 Heavy (IIRC there WAS a plan for such a thing in the early days) achieve. Maybe with the core as "second" stage.
Plus: No need for new Kestrels.
Minus: Complex configuration
But: might this actually challenge the Vega?

[Hauerg]

Edit: Of course the core engine would be throttled soon after liftoff.

[Nomadd]

I could see spacex "selling" end-of-life merlins to a subsidiary that would repackage them into expendable low cost launchers. customers would trade reliability for dirt-cheap orbital access. it would be a huge boon for universities and startups.

Such a subsidiary would also be a great "minor leagues" for spacex to train up talent.

I couldn't. They expose themselves to a huge liability for little benefit. If the engine isn't OK for a Falcon, it's not OK for anything else except testing.

[ChrisWilson68]

I could see spacex "selling" end-of-life merlins to a subsidiary that would repackage them into expendable low cost launchers. customers would trade reliability for dirt-cheap orbital access. it would be a huge boon for universities and startups.

Such a subsidiary would also be a great "minor leagues" for spacex to train up talent.

There's no such thing as an "end-of-life" Merlin engine.

Musk has said that there is no limit to how many times a Merlin could be used.  After 30 or so firings a few components would have to be replaced, then it could continue to be used.

[Stan-1967]

I could see spacex "selling" end-of-life merlins to a subsidiary that would repackage them into expendable low cost launchers. customers would trade reliability for dirt-cheap orbital access. it would be a huge boon for universities and startups.

Such a subsidiary would also be a great "minor leagues" for spacex to train up talent.

There's no such thing as an "end-of-life" Merlin engine.

Musk has said that there is no limit to how many times a Merlin could be used.  After 30 or so firings a few components would have to be replaced, then it could continue to be used.

Come on host!  Let's not let the good become the enemy of the perfect!  The elasticity of the market will take some time to create payloads for reusable hardware.  SpaceX's entire manifest is probably presumed to be deliverable with new components.  That means lots of Merlins are going to be laying around very soon!  There are 9 now, could be 18-27 in the next 60 days.  That years of launches in the smallsat space. 

There are paper rockets to be dreamed of Merlin 1D FT's that need to be lit!  I'm working on my paper rocket in my spare evening time.   Will have some ready to be unvieled later tonight.  ( after all that work and family stuff is done for the day )

[Lars-J]

I could see spacex "selling" end-of-life merlins to a subsidiary that would repackage them into expendable low cost launchers. customers would trade reliability for dirt-cheap orbital access. it would be a huge boon for universities and startups.

Such a subsidiary would also be a great "minor leagues" for spacex to train up talent.

I couldn't. They expose themselves to a huge liability for little benefit. If the engine isn't OK for a Falcon, it's not OK for anything else except testing.

Agreed. This has nothing but downsides for SpaceX. Selling new engines is one thing, but selling used engines is a surefire way to get blamed for every launch mishap.

[ChrisWilson68]

I could see spacex "selling" end-of-life merlins to a subsidiary that would repackage them into expendable low cost launchers. customers would trade reliability for dirt-cheap orbital access. it would be a huge boon for universities and startups.

Such a subsidiary would also be a great "minor leagues" for spacex to train up talent.

There's no such thing as an "end-of-life" Merlin engine.

Musk has said that there is no limit to how many times a Merlin could be used.  After 30 or so firings a few components would have to be replaced, then it could continue to be used.

Come on host!  Let's not let the good become the enemy of the perfect!  The elasticity of the market will take some time to create payloads for reusable hardware.  SpaceX's entire manifest is probably presumed to be deliverable with new components.  That means lots of Merlins are going to be laying around very soon!  There are 9 now, could be 18-27 in the next 60 days.  That years of launches in the smallsat space. 

And SpaceX has plans for those engines.  They're not just surplus.  Yes, they're going to have a bunch of them accumulating over the next couple of years.  But, after that they'll be using them to fly payloads.  By the time a new F1-class launcher could be ready, SpaceX will be flying all their engines.

[RoboGoofers]

And SpaceX has plans for those engines.  They're not just surplus.  Yes, they're going to have a bunch of them accumulating over the next couple of years.  But, after that they'll be using them to fly payloads.  By the time a new F1-class launcher could be ready, SpaceX will be flying all their engines.

This sounds like a paperwork nightmare, and defeats the idea of scaling up production to reduce per-unit manufacturing costs.

i think they'll just test and fly until they have a clear mean time to failure and then retire them.

but back to the topic, i only mentioned the used merlins because there might be a lot of them sitting around some day that could be used on a reborn F1.

[Stan-1967]

I could see spacex "selling" end-of-life merlins to a subsidiary that would repackage them into expendable low cost launchers. customers would trade reliability for dirt-cheap orbital access. it would be a huge boon for universities and startups.

Such a subsidiary would also be a great "minor leagues" for spacex to train up talent.

I couldn't. They expose themselves to a huge liability for little benefit. If the engine isn't OK for a Falcon, it's not OK for anything else except testing.

Agreed. This has nothing but downsides for SpaceX. Selling new engines is one thing, but selling used engines is a surefire way to get blamed for every launch mishap.

This is "Blood sucking lawyer 101" basics.   Buyer beware.   Assignment of risk can easily be transferred to the 3rd party.   SpaceX  could remove the engine, stick it on a test stand, and certify is still works to spec. and is free from damage per identifiable criteria.   Beyond that, the risk has transferred. 

[ChrisWilson68]

And SpaceX has plans for those engines.  They're not just surplus.  Yes, they're going to have a bunch of them accumulating over the next couple of years.  But, after that they'll be using them to fly payloads.  By the time a new F1-class launcher could be ready, SpaceX will be flying all their engines.

This sounds like a paperwork nightmare, and defeats the idea of scaling up production to reduce per-unit manufacturing costs.

Huh?  I really don't understand what you're saying here.  Are you saying you don't think SpaceX will refly their engines?  They've gone to an awful lot of trouble to recover and refly whole stages.

I'm not sure what paperwork nightmare you're worried about.  A 747 doesn't have a paperwork nightmare to fly its engines on each flight.  There's no reason in principle it has to be different for a rocket.  And no reason to think the paperwork for reusing an existing engine would be any worse than the paperwork for a newly-built engine.

i think they'll just test and fly until they have a clear mean time to failure and then retire them.

Knowing the mean time to failure doesn't necessarily mean it makes sense to set a retirement date for a piece of hardware.  For example, incandescent light bulbs don't last forever, but the chance of one failing in any given one-minute interval is nearly constant, not dependent on how long its been operating.  And an engine isn't a monolithic block.  Parts that wear out can be replaced.  With aircraft engines, after a given number of hours they need to be overhauled, and it's expensive, but the engines aren't just thrown away.

Finally, for some missions one or more core stages is expended for improved performance.  As long as that continues to be true, engines will be going away on the expended cores, so there's a limit to how many flights will ever go on any given engine even though no end-of-life engine is ever discarded in a way that makes it available for a cheap, high-risk launch vehicle.

but back to the topic, i only mentioned the used merlins because there might be a lot of them sitting around some day that could be used on a reborn F1.

But they'll only temporarily be sitting around, waiting to be reflown on future Falcon 9 and Falcon Heavy flights.

[ChrisWilson68]

I could see spacex "selling" end-of-life merlins to a subsidiary that would repackage them into expendable low cost launchers. customers would trade reliability for dirt-cheap orbital access. it would be a huge boon for universities and startups.

Such a subsidiary would also be a great "minor leagues" for spacex to train up talent.

I couldn't. They expose themselves to a huge liability for little benefit. If the engine isn't OK for a Falcon, it's not OK for anything else except testing.

Agreed. This has nothing but downsides for SpaceX. Selling new engines is one thing, but selling used engines is a surefire way to get blamed for every launch mishap.

This is "Blood sucking lawyer 101" basics.   Buyer beware.   Assignment of risk can easily be transferred to the 3rd party.   SpaceX  could remove the engine, stick it on a test stand, and certify is still works to spec. and is free from damage per identifiable criteria.   Beyond that, the risk has transferred.

That might be a logical way for the legal system to work, but it is not the way the legal system works in the United States.  The lawyers would still come after SpaceX no matter what agreement has been signed.

[Dante80]

Guys..we are theory-crafting about imaginary/alternate reality paper rockets in this thread. The M1-Ds can be brand new, taken from a scrapyard or exchanged for Vermulian Brandy.

Back to the topic if we can..<3

[Stan-1967]

Well I took the leap last night to give my best effort at making my own new "Phoenix" F1 class vehicle and testing it out on a simulator linked to by this site in the archives at Silverbird Astronautics.
http://www.silverbirdastronautics.com/LVperform.html

This was the first time I have ever done an exercise like this.  I have watched many other here do similar, some of you are very very good at it.  I do not profess to be good at all.

My designs started with the specifications for using the Merlin 1D FT engine w/ 756 kN thrust, and building the vehicle around that.  I also made an early decision to make the new vehicle with a 2m core, not the 1.7 I believe the old F1 had.  I think the Merlin 1D FT is too much rocket to stick on that small a diameter core without getting something too long and bendy.

I also wanted to make a better S2, so I selected to use a 100kN Methane upper stage.  ( Darma Technolgies CHASE 10 ) I had to guess what a vacuum engine could do for ISP, and guessed 350s.

G's at liftoff were set to be 1.18, so the mass of the complete vehicle would then be 65329 kg's.

After some iterations on the calculations, my mass distribution is a follows

Stage 1:
Dry mass = 3461 kg
Propellant = 55368 kg
Thrust = 756 kN
ISP avg = 304

Stage 2:
Dry mass = 619
Propellant = 5881
Trust = 100 kN
ISP = 350
Fairing 160 kg

I double checked that at 70% thrust on the Merlin just before MECO the vehicle was at 5.42 G's, so I think the ride up is OK.

Here is what the calculations returned:
Mission Performance:
Launch Vehicle:     User-Defined Launch Vehicle
Launch Site:     Cape Canaveral / KSC
Destination Orbit:     185 x 185 km, 45 deg
Estimated Payload:     1687 kg
95% Confidence Interval:     1294 - 2172 kg

That seems to square with increased performance that would be expected with a new FT Merlin over the old Merlin 1A and 1C.

This exercise also demonstrated that Merlin 1D FT is not a "smallsat" class engine.  I think it could compete against the VEGA launcher quite well.

Final note on the 2m core.  My intent with this was to made my next "Phoenix F1" into a LRB variant for the F9H vehicle.  I like the F9H, but I can't help note that the side boosters are using a crap ton of performance to carry its fuel for its full burn time of around  and then have to turn the rocket around for RTLS.  It's cool and everything, but very inefficient.  I wanted to see how much fuel I could pack into a 2 m core, and then see how quickly I can expend it with more engines.  The Merlin 1D FT's amazing T/W make that a no brainer early in the flight.   A 2m core would have room for 2 engines no problem, and possibly 3 if a skirt or aeroshells were added.

My next paper exercise is to make a 2m F1 class LRB that empties its tanks in around 90 seconds ( after Max Q ) and then jettisons.  Given how light the empty booster would be, a fly back booster might make sense, as it wont be too far down range. 

[Stan-1967]

Guys..we are theory-crafting about imaginary/alternate reality paper rockets in this thread. The M1-Ds can be brand new, taken from a scrapyard or exchanged for Vermulian Brandy.

Back to the topic if we can..<3

After that post, I went to design my paper rocket last night! ( see above!)  I then realized maybe a I had a post for the "You know you are a Space Geek when" thread.   I started humming the old Dire Straights song, "Money for Nothing"

But in my head I was also singing " I want my M1D,  I want my M1D"....

[mikelepage]

Well now, this is my kind of thread.

Well I took the leap last night to give my best effort at making my own new "Phoenix" F1 class vehicle and testing it out on a simulator linked to by this site in the archives at Silverbird Astronautics.
http://www.silverbirdastronautics.com/LVperform.html
[...]
Here is what the calculations returned:
Mission Performance:
Launch Vehicle:     User-Defined Launch Vehicle
Launch Site:     Cape Canaveral / KSC
Destination Orbit:     185 x 185 km, 45 deg
Estimated Payload:     1687 kg
95% Confidence Interval:     1294 - 2172 kg
[...]

So... assuming I was a billionaire, I had a couple of Mercury style capsules as payloads (m = 1400kg), and a death defying love of Koalas, I could have lunch in Cape Canaveral, get on a Phoenix at 3pm, have breakfast in Taronga zoo, Sydney (at 4pm/8am), get on another Phoenix at 5pm/9am and be back at KSC in time for dinner?

[fwskungen]

what about using 1 or 2 Super Draco engines for the upper stage? they are very lightweight and mostly need a upgrade for space flight via mounting a large bell on this

[Dante80]

what about using 1 or 2 Super Draco engines for the upper stage? they are very lightweight and mostly need a upgrade for space flight via mounting a large bell on this

One would do (for the amount of thrust needed), but the Isp would be much worse than what ye olde Kestrel had. Even with a bigger nozzle.

[RotoSequence]

what about using 1 or 2 Super Draco engines for the upper stage? they are very lightweight and mostly need a upgrade for space flight via mounting a large bell on this

One would do (for the amount of thrust needed), but the Isp would be much worse than what ye olde Kestrel had. Even with a bigger nozzle.

But would it be enough?

I remember someone ball-parking some dramatic payload improvements in the Falcon 9 in GEO missions by adding a third stage powered by a Super-Draco derivative. I wonder if there's any possibility of sane overlap in a Falcon 9 Super-Draco third stage and a Falcon 1e Super-Draco second stage?

[Dante80]

For a Falcon9/Falcon Heavy Payload Assist Module, the idea of using superdraco for the application might have some merit for deep space missions like interplanetary probes, or insertions to GEO. I think though that SpaceX have decided to maximize the Falcon architecture recoverable/re-usable fraction, so a development program like that might be viewed by them as counter-intuitive.

For an imaginary F1e, I think that the superdracos' low Isp would help less than a better Kestrel2.