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Skylon

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On the topic of trying to SSTO the Starship, I'll take this quote from a chapter of Right Side Up:

 

“A marginal SSTO is a great TSTO.”
“By extension, a marginal TSTO is a great 3STO.”

Hand-written notes on NASA MSFC memo during STS planning, 1969

 

The challenge of trying to build a reusable SSTO for Earth is immense. Every time people have tried, the design doesn't work as planned, and increases in dry mass cut the already marginal payload to negligible levels. Cut things in half, though, and recover the halves separately, and the challenges become much more tractable.

I doubt there'll be a shortage of Superheavies for the Starship; they're basically overgrown Falcon 9 boosters. The recovery challenges are much less severe when you're talking about merely hypersonic speeds; even ordinary aluminum can take that sort of heat load. If space launch really picks up and they simply can't turn them around fast enough, SpaceX can... build more Superheavies.

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^^^exactly.

On top of that, refilling operations in SpaceX videos make it look like it happens maybe the next orbit. In KSP, that could totally be a thing. Launching from someplace that is not the equator, it's not a thing at all, they need to wait until the next overflight. That means a 24 hour (ish) turn around is all they ever really need.

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5 hours ago, Starman4308 said:

“By extension, a marginal TSTO is a great 3STO.”

Not agreed in case of reusability.
You can return the 1st stage to the launch center just by making a horizontal retroburn after the separation.
You can land the last stage right in the launch center just by deorbiting in in proper time.

But everything in between you should catch or find in random area on the opposite well, 90°-rotated, side of the planet, and bring back.

So, a marginal reusable TSTO is just a marginal reusable TSTO.

Edited by kerbiloid
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1 hour ago, sevenperforce said:

They were never interested in propulsive landing for Earth.

NASA contractors proposed numerous VTVL designs. None ever got the nod, obviously, but I'm sure they were considered at some level.

Douglas and Boeing both made such proposals, as well as perhaps Grumman.

 

NASA contracted the designs, apparently (some googling). Aerojet, Space tech Labs, Douglas, RAND, Martin Marietta, General Dynamics, and Boeing most all came up with VTVL reusable designs (a could look to have some sort of glider, instead).

Oh, and the later, Chrysler SERV concept NASA looked at (early 70s). Boeing had 2 concepts NASA looked at in the mid 70s.

Edited by tater
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16 hours ago, Scotius said:

Or have a fuel depot in LEO, and send Starships up in SSTO mode when needed (or when there is a shortage of available SuperHeavies :) ) to be refuelled in space.

What's the point when there's no payload?

1 hour ago, sevenperforce said:

They were never interested in propulsive landing for Earth.

Also, EDL in a lawn dart is no small challenge.

https://en.wikipedia.org/wiki/McDonnell_Douglas_DC-X?wprov=sfla1

They actually got to the Grasshopper stage before this got canceled.

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3 hours ago, Xd the great said:

They could hit the Nevada desert and no one would care...

Oh, and also get some glass for free.

Um acktually, the rocket in Tintin used chemical propulsion for takeoff and landing, only switching to nuclear power when they reached space :)

 

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2 hours ago, DAL59 said:

Um acktually, the rocket in Tintin used chemical propulsion for takeoff and landing, only switching to nuclear power when they reached space :)

Presumably something like LANTR?

5 hours ago, tater said:
5 hours ago, sevenperforce said:
7 hours ago, Xd the great said:

How come NASA has never considered a tintin-looking rocket for the STS?

They were never interested in propulsive landing for Earth.

NASA contractors proposed numerous VTVL designs. None ever got the nod, obviously, but I'm sure they were considered at some level.

Douglas and Boeing both made such proposals, as well as perhaps Grumman.

I misread @Xd the great's post and thought he said SLS. NASA has never been interested in earth-propulsive landing for the SLS since it was all about reusing STS hardware. 

There were definitely early STS designs that were VTVL. Restartability and throttleability of rocket engines was considered problematic, which is why the Chrysler SERV would have carried no less than forty turbine jet engines for hover-light touchdown after entry and descent.

3 hours ago, ThatGuyWithALongUsername said:

https://en.wikipedia.org/wiki/McDonnell_Douglas_DC-X?wprov=sfla1

They actually got to the Grasshopper stage before this got canceled.

The DC-X program started a decade after STS was already flying.

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Absolutely, Constellation/SLS was all about reusing Shuttle stuff to save money

<starts laughing hysterically>

Spoiler

still laughing...

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

You get the idea.

</end laughing>

Edited by tater
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54 minutes ago, Ultimate Steve said:

DxOVKFRWwAAPV9g.jpg:large

Am I the only one that doesn't mind too much and still likes the style? As far as aesthetics go it could use something to break up the white in the middle, but it's not terrible.

Yeah, umm.......that's actually not so bad at all.

The face shields were only black because there was a manikin in them before.

Accents are whatever. Close enough. Also note that they look overly bulky because Behnken's gloves are folded back into his cuffs and Hurley's are hanging loose, whereas during flight they would be properly engloved.

But yeah, it looks like a proper bridge flight suit. Knee pads are cool. I could see someone saluting that!

On another note...

Granted, we already knew this. But it got me thinking: in the event of catastrophic chute failure, the SuperDracos could absolutely kick in and make splashdown survivable. I wonder if there is contingency programming for this. Granted, the risk of chutes failing in triplicate are unbelievably low, but I don't think adding that programming would cause any problems.

 

Edited by sevenperforce
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18 minutes ago, Ultimate Steve said:

DxOVKFRWwAAPV9g.jpg:large

Am I the only one that doesn't mind too much and still likes the style? As far as aesthetics go it could use something to break up the white in the middle, but it's not terrible.

It’s also a picture from a bad angle with bad (washed out) lighting. A good photographer could easily make an epic looking image of these starmen.

However I think the meme maker is also commenting that the astronauts are older and more heavy-set than figure in the promo. 

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7 minutes ago, sevenperforce said:

 

Granted, we already knew this. But it got me thinking: in the event of catastrophic chute failure, the SuperDracos could absolutely kick in and make splashdown survivable. I wonder if there is contingency programming for this. Granted, the risk of chutes failing in triplicate are unbelievably low, but I don't think adding that programming would cause any problems.

Wasn't that an old test?

I would also think that If they decided to touch down on land, the SD's could be used to cushion the landing, much like how Soyuz uses solid rockets at touchdown

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1 hour ago, sevenperforce said:

But it got me thinking: in the event of catastrophic chute failure, the SuperDracos could absolutely kick in and make splashdown survivable. I wonder if there is contingency programming for this. Granted, the risk of chutes failing in triplicate are unbelievably low, but I don't think adding that programming would cause any problems.

Complexity is just as bad in software engineering as hardware engineering. It's something where the chance of this being necessary has to be weighed against the cost of developing and validating the software, plus the risk of the propulsive landing routine accidentally activating on a nominal landing, plus the risk of it somehow interfering with the parachute landing software, plus NASA bureaucracy.

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12 hours ago, sevenperforce said:

Granted, we already knew this. But it got me thinking: in the event of catastrophic chute failure, the SuperDracos could absolutely kick in and make splashdown survivable. I wonder if there is contingency programming for this. Granted, the risk of chutes failing in triplicate are unbelievably low, but I don't think adding that programming would cause any problems.

 

I am not so sure if they have enough fuel after deorbiting to do this.

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8 minutes ago, Xd the great said:

I am not so sure if they have enough fuel after deorbiting to do this.

It was designed for propulsive landing after de-orbit. I think the only design change is not doing the landings, I doubt they would have resized the fuel tanks. Of course I could very well be wrong, so take this with a grain (or mountain) of salt.

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