SpaceX Tuesday...

[Flooble]

annodomini2 said:

CraigyMc said:

John_S4x4 said:

I have heard on the grapevine, that there is $96 million of US military funding in the budget for SpaceX, as the US military are interested in the concept of having 100 tons of payload land anywhere on earth, within the hour.

So how are they going to do that ?

Depends. Is it allowed to be in space beforehand?

Is it a bundle of tungsten rods?

Suborbital hop, they can probably do it with Starship with a partial fuel load.

I think he was talking about the Strategic Defence Initiative "Rods from God" plan: https://www.popsci.com/scitech/article/2004-06/rod...

[MartG]

SXM-8 launch went well https://www.youtube.com/watch?v=bgtDRR2F2wA

[annodomini2]

louiechevy said:

Heres how spacex aim to get anywhere on earth in under an hour.

https://youtu.be/zqE-ultsWt0

I respect that is SpaceX's video, but they wouldn't need the booster to do a sub-orbital hop with Starship, at least for a 90deg arc, 180 may require the Booster due to the DeltaV requirements and not having re-entry G forces that kill the passengers, but for Military equipment deployment it's probably fine.

Theoretically you can get up to ~50km and skip across the top of the atmosphere, it would probably be uncomfortable and the craft would need to be designed for it.

[Flooble]

MartG said:

SXM-8 launch went well https://www.youtube.com/watch?v=bgtDRR2F2wA

Crazy how launching and landing on a boat has become so routine barely anyone mentions it now.

I think I saw that they are launching every 9 days and are currently sitting on a 98.3% success rate. Although just as interestingly it's now over 100 launches since a failure?

I am beginning to see the logic in the plan for Starship where they intend to make it crew-safe by just flying it a lot.

[Beati Dogu]

The test flight won’t actually be truly orbital, but ballistic. They won’t need to flip Starship around and fire the engines to slow from orbital speeds. Instead it will renter more naturally. Good enough for initial testing and a demonstration of basic point to point flight. The military will like that.

Could be that they configure one of the two former oil rigs as a pure landing pad. I.e strip all the superstructure and just have a flat top. This would be much simpler to do and would allow them to attempt a booster landing sooner rather than later. Phobos is round the coast in Mississippi at the moment being converted for SpaceX. This might be the landing vessel.

The second former oil rig with actual launch capability is more complicated and can come once they sorted more important things out. The other rig, Deimos, is in port in nearby Brownsville. It too is being worked on for operations next year. That one will probably be the launch vessel.



Good to see that Sirius XM launch go well and the booster landing for the 3rd time.

[annodomini2]

Beati Dogu said:

The test flight won’t actually be truly orbital, but ballistic. They won’t need to flip Starship around and fire the engines to slow from orbital speeds. Instead it will renter more naturally. Good enough for initial testing and a demonstration of basic point to point flight. The military will like that.

Could be that they configure one of the two former oil rigs as a pure landing pad. I.e strip all the superstructure and just have a flat top. This would be much simpler to do and would allow them to attempt a booster landing sooner rather than later. Phobos is round the coast in Mississippi at the moment being converted for SpaceX. This might be the landing vessel.

The second former oil rig with actual launch capability is more complicated and can come once they sorted more important things out. The other rig, Deimos, is in port in nearby Brownsville. It too is being worked on for operations next year. That one will probably be the launch vessel.



Good to see that Sirius XM launch go well and the booster landing for the 3rd time.

A booster is still going to be iro 200t empty, without infrastructure to move it, if it does land will present other challenges.

Flyback and land on maybe a more remote pad than the current starship one may be more practical to begin with.

[Flooble]

Beati Dogu said:

The test flight won’t actually be truly orbital, but ballistic. They won’t need to flip Starship around and fire the engines to slow from orbital speeds. Instead it will renter more naturally. Good enough for initial testing and a demonstration of basic point to point flight. The military will like that.

Could be that they configure one of the two former oil rigs as a pure landing pad. I.e strip all the superstructure and just have a flat top. This would be much simpler to do and would allow them to attempt a booster landing sooner rather than later. Phobos is round the coast in Mississippi at the moment being converted for SpaceX. This might be the landing vessel.

The second former oil rig with actual launch capability is more complicated and can come once they sorted more important things out. The other rig, Deimos, is in port in nearby Brownsville. It too is being worked on for operations next year. That one will probably be the launch vessel.

Good to see that Sirius XM launch go well and the booster landing for the 3rd time.

Can the Phobos rig maintain position without all the stuff they (will) have removed? I am pretty sure I saw somewhere that it was a six-month contract to do the strip-down, without mention of then installing the dynamic positioning kit and so forth that would be needed for it to not drift. Granted the booster perhaps has more ability to adjust its landing point (it can throttle down to a <1.0 TWR) but hitting a moving target seems like a bit more challenge than you'd really want on a first flight.

Oh, I just realised you didn't explicitly say you expected them to make a landing on the first flight.

[Beati Dogu]

They’re pretty cagey about what they’re up to. We probably wouldn’t know about the rigs yet if a bored space photographer hadn’t decided to take a look at the docks, seen a couple of rigs named after the moons of Mars and put 2 and 2 together. They were bought through a shell company like Boca Chica itself. It avoids publicity and means they don’t have to pay top dollar for everything.


Meanwhile landing ship “Of Course I Still Love You” is back in port to offload booster B1067, which did the Dragon launch to the ISS. Word is that it will be headed round to the Pacific to support rocket launches from Vandenberg, California.

The new 3rd landing ship “A Shortfall of Gravitas” will be moved over to Florida when it’s ready.

[Caruso]

Specs of the 2 rigs they bought: http://s1.q4cdn.com/651804090/files/Documents/Broc... which states they have dynamic positioning which I imagine they will keep. They are also capable of anchoring themselves in shallower water - the spec states 2500ft long anchor cables.

[CraigyMc]

I see SpaceX's primary competitor have announced that the owner of the company is off to space in a month. Interesting that Bezos will have a go before Musk.

[ninja-lewis]

Unofficial animation of Super Heavy + Starship test flight

https://youtu.be/iFt_LsFRFEQ

[xeny]

Looking at the animation, I'm slightly wondering if it'd be beneficial to do at least some of SuperHeavy's fall through the atmosphere in a horizontal attitude - you'd get so much extra drag, and it's enough stubbier than a Falcon 9 first stage it wouldn't be so bad to flip it through 90 degrees for landing

Also, Elon talks about a thrust/mass ratio of 1.5:1 at launch - that's making me think that vehicle acceleration as SuperHeavy comes close to shutdown is going to be quite high - they're going to be shutting engines down quite extensively to keep acceleration levels tolerable when they start carrying human passengers.

[annodomini2]

~220t thrust per raptor *29 = ~6380t thrust at take off.

Each raptor burns ~600kg of fuel per second

• 29 = ~17.4t of fuel per second.

3400t of propellant gives total burn time of 195 seconds at full thrust.

Boost will be 159 seconds, leaving approximately 36 seconds of burn time for "landing".

[annodomini2]

xeny said:

Looking at the animation, I'm slightly wondering if it'd be beneficial to do at least some of SuperHeavy's fall through the atmosphere in a horizontal attitude - you'd get so much extra drag, and it's enough stubbier than a Falcon 9 first stage it wouldn't be so bad to flip it through 90 degrees for landing

Also, Elon talks about a thrust/mass ratio of 1.5:1 at launch - that's making me think that vehicle acceleration as SuperHeavy comes close to shutdown is going to be quite high - they're going to be shutting engines down quite extensively to keep acceleration levels tolerable when they start carrying human passengers.

No header tanks for flip landing on superheavy.

[Beati Dogu]

CraigyMc said:

I see SpaceX's primary competitor have announced that the owner of the company is off to space in a month. Interesting that Bezos will have a go before Musk.

I’m not sure Blue Origin count as a SpaceX competitor when all they have so far is vapourware. They’re competing with Virgin Galactic perhaps, but I expect the niche high altitude joyride market is big enough for both of them.

[CraigyMc]

Beati Dogu said:

CraigyMc said:

I see SpaceX's primary competitor have announced that the owner of the company is off to space in a month. Interesting that Bezos will have a go before Musk.

I’m not sure Blue Origin count as a SpaceX competitor when all they have so far is vapourware. They’re competing with Virgin Galactic perhaps, but I expect the niche high altitude joyride market is big enough for both of them.

They've launched New Shepard 15 times and landed it 14 (the first landing attempt failed, all others succeeded).

I dunno what your definition of vapourware comes from. The hardware they will fly Bezos up on was built 3 years ago.
Sure, they aren't as advanced as SpaceX but they are on a similar arc.

[Beati Dogu]

New Shepard doesn’t compete with SpaceX at any level. New Glenn is vapourware at the moment and will not even begin to fly for a couple of years.

Rocket Lab is more of a competitor than Blue Origin right now.

ULA, Arianespace and Roscosmos could be said to be true competitors, be really they just get the crumbs these days. That’s why they’re working on newer, cheaper rockets.

[hidetheelephants]

CraigyMc said:

Beati Dogu said:

CraigyMc said:

I see SpaceX's primary competitor have announced that the owner of the company is off to space in a month. Interesting that Bezos will have a go before Musk.

I’m not sure Blue Origin count as a SpaceX competitor when all they have so far is vapourware. They’re competing with Virgin Galactic perhaps, but I expect the niche high altitude joyride market is big enough for both of them.

They've launched New Shepard 15 times and landed it 14 (the first landing attempt failed, all others succeeded).

I dunno what your definition of vapourware comes from. The hardware they will fly Bezos up on was built 3 years ago.
Sure, they aren't as advanced as SpaceX but they are on a similar arc.

Why are they not selling payload to satellite peeps? Seems an expensive way to get into space.

[Polite M135 driver]

hidetheelephants said:

Why are they not selling payload to satellite peeps? Seems an expensive way to get into space.

Because their vehicle doesn’t go/can’t get into orbit.

[xeny]

annodomini2 said:

No header tanks for flip landing on superheavy.

That's a design decision that it isn't worth it - more slightly wondering why they made that decision.