SpaceX reusable launcher (Grasshopper) thread 2


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Raptor looks like an absolute beast of an engine - will these replace the Merlin 1D's in the first stage?

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No, far too large...over 1,000,000 lbf of thrust each. It goes into a huge new launcher 3x the width of a Falcon 9 - 10 meters wide vs F9's 3.7 meters.

No name yet, most are calling it the Big F'ing Rocket or BFR. 9 Raptor engines in the first stage, 1-2 Raptors in the upper stage and a monsterous payload capacity, estimates run up to 180-200 tonnes.

BFR may fly other things, but it and its even larger (!!) triple-core big brother are optimixed for fast manned missions to Mars.

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BFR may fly other things, but it and its even larger (!!) triple-core big brother are optimixed for fast manned missions to Mars.

 

Can you imagine the sheer NOISE launching one of those things will make?!

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So that's the super heavy lift rocket they are planning post F9 Heavy? If they have the engine almost ready they must be quite far along on the rocket itself?

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The component work at Stennis will last at least a year, then they can put it together and test the whole engine.

There is a preliminary launch year, but it's still embargoed. They may announce it in their ISDC 2014 presentation on May 17. Or not.

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  • 5 weeks later...

F9R Dev-1 may not fly that many more times. The next flight may be soon.

Once it's done testing on DragonFly starts at McGregor and F9R Dev-2 testing at SpacePort America in New Mexico will be the focus. That pad was recently completed.

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  • 2 weeks later...

No. F9R Dev 1 uses a single engine, so it's not much louder than the Merlin engine qualification tests that run almost daily.

These extra loud tests are stage qualifications. They put a first stage up on the stand and fire all 9 engines for almost 3 minutes. Under the right conditions (thermal inversion) it can shake everything for 10-20 miles.

Wait'll they test Falcon Heavy - it has 27 engines.

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And the latest print copy of Aviation Week has info that BFRs Raptor engine has grown more powerful again. Tom Mueller, SpaceX's propulsion guru, confirmed it at a late May space propulsion conference in Cologne.

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The big thing is that with the recent massive thrust increase in Raptor, made easier by it being a full-flow staged combustion engine, a single core now has the lift of the previous tri-core Heavy.

A more capable single core largely eliminates the need for the tri-core Heavy - simplifying construction, ground operations and reusability. Sounds like a plan.

This things going to be a freakin' beast.

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How to say it without saying it...hmmmmm. Let's talk the most recent "old" number people have been using to calculate tank volumes etc. and model its performance.

Elon Musk said a couple months ago it would have a core with 15,000,000 lbf of thrust. Propulsion VP Tom Mueller said 9 engines.

15.000,000 lbf ? 9 = ~1,668,000 lbf.

Sea level or vacuum? SpaceX usually specs the vacuunm number.

The latest Raptor thrust number (late May) has people recalibrating their models again.

Kind of expected because full-flow SC's scale very well, which is why the thrust numbers have grown the more they work on it. Little tweaks that increase flow give huge results without enlarging the chamber or causing pump overheating.

Because of the Isp of methane its LEO lift is enough to make you spray your keyboard.

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Yup. ~2x the thrust Saturn V, lighter, and with a higher specific impulse due to using methane instead of kerosene. And it may not be done growing yet. Not to mention what a vacuum rated Raptor upper stage engine could mean (5-6x the thrust of SLS's J-2X.)

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They're not talking about Raptor much save for May's propulsion conference. The speculation is they're trying to avoid the wrong congress critters (Sen. Shelby etc.) from getting the word his pet projects (SLS, Orion) are outgunned.

That delay won't last much longer because of the SLS replacement project congress is insisting on. The main competitors are shaking out to be AeroJet-Rocketdyne (AJ-1) and SpaceX (Raptor).

The *really* funny thing is that in recent promos AJR touts AJ-1 as a replacement for SpaceX's own Merlin engines on Falcon 9 - which would mean a net thrust decrease of at least 30% :ROFL:

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Not only a performance decrease, but also an increase in launch price. Got to love the old aerospace contractors... dreaming of staying in business.

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