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That is the NASA Causeway and it is not accessible to the public. You can only get there if you buy tickets, are credentialed media, or have a VIP hookup.
Does KSC typically sell tickets for 39A launches?

Edit: Looks like the answer has been no for the last few CRS missions. Well, that leaves Port Canaveral and the Jetty Park as the remaining options from that website, and they are very far from the launch pad. Is there anything else I should consider? If not I may just try to get close to 39A, as it might not be worth trying to see the landing up close.
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And it seems like they have also decided that the Dragon 2 propulsive landing - while cool and not completely ruled out in the future - is an evolutionary dead end.

Propulsive capsule-landing always seemed like an evolutionary dead end.

It seems critical to the goal of rapid reuse, right now the flight rate doesn't require it, but it may be useful in the future if LEO crew traffic picks up significantly. A propulsive landed capsule + reuse of both F9 stages has the potential to bring down the ticket price to LEO significantly.

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Now they're stuck with a suboptimal design, looks like the first serious misstep to me.

They have a good enough system for now, SpaceX is not after the optimal solution, they go for the most cost effective one.
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Considering YuanWang 3/5/6/7 have returned, BeiDou-3 will not launch in the coming weeks
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... first order of business is to prove them wrong ...

You can't prove anything to a fool.
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And it seems like they have also decided that the Dragon 2 propulsive landing - while cool and not completely ruled out in the future - is an evolutionary dead end.

Propulsive capsule-landing always seemed like an evolutionary dead end. Now they're stuck with a suboptimal design, looks like the first serious misstep to me.
Seemed to whom?

I don't see them being a "serious misstep", since Dragon is volume limited  and the NASA contracts remain the same.

Throwing away an abort tower each time would have been more expensive.

Plus, the R&D is not totally lost, and wherever propulsive landings you'll see in the future, it'll have D2 genes.

(And you will see propulsive landings in the future - what else is there that scales?)

A controlled landing using thrust differential on side mounted hypergolic engines and a ballast sled is absolutely a dead end. BFS lands just like F9, using thrust vectoring.

That being said, their abort system is still clearly the best design in use since it has no separation events and is reusable. I don't see it as a misstep. FH was way harder than they thought but they chose to continue with it; propulsively landing D2 proved to be harder than they thought and they shelved it for lack of utility.
The ballast slide replaces fins, not engines.

Differential thrust, if appropriate, is a more responsive system then a gimbal.

However, since ITS is a second stage and an interplanetary vehicle, angled side thrusters don't make sense.

So all we have here is "customer didn't want it, and we have bigger fish to fry".

Yes, exactly. If the customer doesn't want it and you don't need it, why in the world would you build it?

Sure, perhaps you could build BFS with a dragon style landing system, but they aren't. The technology is totally different and there will be very little data shared between D2 and BFS.
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SpaceX General Section / Re: SpaceX Falcon Heavy Discussion (Thread 6)
« Last post by su27k on Today at 03:58 AM »
...               

SpaceX can't afford ITS development on its own.  Until they find another partner willing to spend tens of billions of dollars, I wouldn't hold your breath.

...

Not everyone requires tens of billions of dollars to build a launch vehicle.  Recall the study that showed it would have taken $4B to build F9 using NASA's approach, but it actually took $390k (1/10th the estimate)?  Tens of billions becomes a few billion... and the builders have so much relevant experience and applicable technology now.  $1-2B seems reasonable; tens of billions sounds like wishful thinking (a.k.a., denial).

The last sentence is wishful thinking and willful suspension of disbelieve.  F9 development costs are much more because development hasn't finished.  Also, "$1-2B seems reasonable" is seriously delusional.

F9 development is also 15 years on now, if you count F1 - which the $390M figure does. Or 11 years, if you go with the ~$300M spent only on getting F9 flying. The vast majority of the money spend on developing F9 was spent after getting it flying and while it was earning revenue and booking orders.

SpaceX will likely try to get a minimalist ITS flying as quickly as possible, to earn revenue with it, and iterate towards a more capable vehicle. That is their MO. They might eventually dump $15 billion into it, but that of itself doesn't mean it couldn't fly (in minimalist form) for less than $3 billion.

Exactly, it would be a prototype at the start (think F9 v1.0 first flight), probably no refueling capability, nothing related to crew, and may not even have payload bay. It would be just enough to prove the point, which is a reusable super heavy is possible, and SpaceX is fully capable of building it.

So far the majority of aerospace industry and congress is treating ITS like a joke, first order of business is to prove them wrong (again, for the 3rd or 4th time). Then SpaceX can leverage the existing hardware to get additional investment from public and/or private sources to finish the rest.
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And it seems like they have also decided that the Dragon 2 propulsive landing - while cool and not completely ruled out in the future - is an evolutionary dead end.

Propulsive capsule-landing always seemed like an evolutionary dead end. Now they're stuck with a suboptimal design, looks like the first serious misstep to me.
Seemed to whom?

I don't see them being a "serious misstep", since Dragon is volume limited  and the NASA contracts remain the same.

Throwing away an abort tower each time would have been more expensive.

Plus, the R&D is not totally lost, and wherever propulsive landings you'll see in the future, it'll have D2 genes.

(And you will see propulsive landings in the future - what else is there that scales?)

A controlled landing using thrust differential on side mounted hypergolic engines and a ballast sled is absolutely a dead end. BFS lands just like F9, using thrust vectoring.

That being said, their abort system is still clearly the best design in use since it has no separation events and is reusable. I don't see it as a misstep. FH was way harder than they thought but they chose to continue with it; propulsively landing D2 proved to be harder than they thought and they shelved it for lack of utility.
The ballast slide replaces fins, not engines.

Differential thrust, if appropriate, is a more responsive system then a gimbal.

However, since ITS is a second stage and an interplanetary vehicle, angled side thrusters don't make sense.

So all we have here is "customer didn't want it, and we have bigger fish to fry".

8
That's a whole lot of rocket for an Apollo "flags and footprints" redux. Heck, SLS is a whole lot of rocket anyways and that's a problem IMO. I previously asked about your excessive core stage's drymass of 123.6mT and your J-2X US at 16.9mT seems quite light. I started with different assumptions, resulting in different masses for each and a different, though just as capable rocket. If you'd allow me ..........

How I derived these masses is described in the paper. The Block I core dry mass is 100,062 kg, so I believe my value is in the right ball park for a six engine core. I derived my LUS mass from the Saturn V S-II, which has a 35,402 kg dry mass and 452,352 propellant mass.

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Funding wise; The existing EUS and Advanced Booster programs would be cancelled and resources allocated to common bulkhead development, production and re-engineering the business-end of the SHLV. You proposed and outlined the importance of J-2X (as have I and others), but I'd also cancel the RS-25 program, switch AR's production contract to J-2X and use RS-68s on the core with almost no modifications.

I did not investigate using RS-68 since that would need to be redesigned so that the ablative nozzle (which won't survive the base heating conditions) is replaced with a regenerative nozzle, practically making it a new engine. That kills any saving from using a "cheaper" engine. This is the same mistake Griffin made when he replaced RS-25 with RS-68 on Ares-V.
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And it seems like they have also decided that the Dragon 2 propulsive landing - while cool and not completely ruled out in the future - is an evolutionary dead end.

Propulsive capsule-landing always seemed like an evolutionary dead end. Now they're stuck with a suboptimal design, looks like the first serious misstep to me.
Seemed to whom?

I don't see them being a "serious misstep", since Dragon is volume limited  and the NASA contracts remain the same.

Throwing away an abort tower each time would have been more expensive.

Plus, the R&D is not totally lost, and wherever propulsive landings you'll see in the future, it'll have D2 genes.

(And you will see propulsive landings in the future - what else is there that scales?)

A controlled landing using thrust differential on side mounted hypergolic engines and a ballast sled is absolutely a dead end. BFS lands just like F9, using thrust vectoring.

That being said, their abort system is still clearly the best design in use since it has no separation events and is reusable. I don't see it as a misstep. FH was way harder than they thought but they chose to continue with it; propulsively landing D2 proved to be harder than they thought and they shelved it for lack of utility.
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I too would prefer a single-launch Lunar mission like 'the good old days'. But forgive me if I missed anything at some stage: have you ever crunched the numbers for a Lunar mission done with dual launches of an SLS Block 1B or similar? I know that would be an expensive mission; though it should allow for a much bigger LM for pretty long stay times on the surface. Also; should allow cargo-only LM versions in single launches of a Block 1B.

There's a rough analysis of the dual Block IB architecture in the paper. A single launch is 20% cheaper per mission, but has a higher development cost due to needing to develop a new core and large upper stage. At 29 missions, total cost (development and mission) single launch becomes cheaper overall.
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