Topic: Interesting stuff about SpaceX Starship (hate the name)

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[Starfox1701]

cool

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The much troubled Boeing Starliner capsule that is supposed to compete with Dragon (and was considered during development to be the most likely to succeed) is now not going to do its next manned launch until April.  Delay after delay.  Looks like this is going to lose a lot of money for Boeing and never be profitable if they don't find a way to turn things around in a VERY dramatic way.

For Starship the BN8 has been retired.  It won't apparently be completed or flown.  No reason given to my knowledge.  Looks like SN25 will be paired with BN9 which is still being worked on.

According to a joint NASA/SpaceX announcement it looks like BN7 with SN24 will launch in early December.  Attempts to get the FAA license are on going for that launch.  It is NOT expected that the booster will be landed this flight (I never though it likely) in spite of an earlier indicator that SpaceX was considering it.  I'm sure they will do the Falcon 9 style ocean landings until they are sure they can get a catch right the first try (Falcon didn't manage the actual attempted landings on the first few tries).

Multiple pressurization tests on BN7 and SN24 this week.  These may be as much tests of the loading system as of the spacecraft if not more so. 

SpaceX is making 7 Raptor 2 engines a week. 

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The Soyuz docked to the ISS is leaking some sort of coolant.  It is unclear at present if it will be able to return the crew to Earth (including an American) or if a replacement will need to be sent.  If they have to come back on a Dragon I propose the name "Project Broomstick" or perhaps "From Elon with Love".

The next SLS launch will not happen until 2025 at the least (dates like that are still hard to believe are real and soon).  So no more American astronauts around the moon until then.

Starship launch is now January 2023.  Anyones guess as to when it will really go.

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Todays launch by SpaceX is the 15th launch for the booster.  The 59th SpaceX launch this year.  There are still 2 scheduled launches to go for this year.

So more records for SpaceX.  How many launches next year?  If Starship proves out and begins launching Starlink v2 it may be fewer launches in 2023 because of the sheer size of Starship allowing the launch of more Starlink satellites per mission.  Then again if they begin practicing refueling launches it could still be a higher cadence. 

If Starship works out and early enough in the year they could also end up using it to do OneWeb and Kuiper launches as well.

Vulcan with the Blue Origin BE-4 engine is currently scheduled for February launching Kuiper satellites. 

Starliner crewed on Atlas is now April.

Dreamchaser is July on Vulcan.

ULA has 9 launches scheduled from January to September and they are perhaps SpaceXs biggest competitor.  In January SpaceX has scheduled 17 launches.  I can only assume that cadence will not continue for SpaceX and that ULA just doesn't have all its launches on the schedule I see.

So what year will SpaceX do 100 launches?

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SpaceX has completed its 60th launch of the year with one more still scheduled. 

61 st launch successful.

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SpaceX has completed its first launch of 2023. 

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Starship has completed its wet dress rehearsal.  It is going to be destacked for the booster 33 engine static fire.  The destacking allows for Starship to have the crane lift points to be removed and to fill the gaps left with heat tiles. 

If all goes well (no date for static fire) the next big thing should be restacking for launch.   

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Possible 33 engine static fire next week.

[Starfox1701]

Cool

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Here is even cooler, an update to the SpaceX Starship page apparently just in the last week or so.

SpaceX’s Starship spacecraft and Super Heavy rocket – collectively referred to as Starship – represent a fully reusable transportation system designed to carry both crew and cargo to Earth orbit, the Moon, Mars and beyond. Starship will be the world’s most powerful launch vehicle ever developed, with the ability to carry up to 150 metric tonnes to Earth orbit reusable, and up to 250 metric tonnes expendable.

For a long time the media has been touting the lower limit of 100 tons to orbit in reusable mode.  The original plan was 100-150+tons with people often attacking that upper limit.  From other things it looks like the reusable 100 tons is to a somewhat higher orbit than the 150 ton LEO but definitely not geosynchronous.

Just to show how these capacities compare to past rocketry:  Skylab 76.5 tons.  The ISS 420 tons.  Skylab in one launch, ISS took many.  Imagine the volume of a 250 tons inflatable ISS module compared to ISS now. 

I would suspect that to really make use of that 250 ton limit they would need a longer Starship to contain the cargo but that had already been talked about.  I wouldn't be surprised if the early refueling missions were with expendables as they will still be working on the landing.  I don't know of any reason they couldn't make the expandable cargo section larger in diameter as well as length.  Other rockets have the upper stage at least partly wider, even Falcon 9 itself.

The 250 tons expendable mode might well be used to launch a nuclear powered rocket in large modules.  Module 1 the engines, multiple modules for propellant.  Life support modules, cargo modules, landers.  Expend the launchers to build a reusable interplanetary manned craft.

[Nemesis]

Possible 33 engine static fire next week.

Apparently sometime tomorrow.  Lets hear her ROAR!  More than twice the thrust of Saturn 5 and SLS. 

[Starfox1701]

Lets see it get all the way up with a payload and get back that what Id like because then we can go back to doing things like work on Hubble

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Probably won't fly this month.  They have deluge system to install (and repair damage done by the static fire).  But just firing these engines is the most powerful rocket ever  fired if it is at full thrust.  More than twice as powerful as SLS.

SpaceX is doing (or has done) a study on repairs to Hubble using Dragon to do a spacewalk for repairs (possibly one of the Axiom Space flights). So it might get repaired with or without Starship.

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Looks like a successful static fire.  But I've only seen video, not details from SpaceX.

I have now seen a claim that 1 engine was turned off just before ignition and one shut down automatically.

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Just a piece of pure speculation on my part.

I wonder if having all these engines so close together they might constrain one another's exhaust like a large extension on the exhaust "bell" and increase the ISP and thrust by a small percentage.  When you are talking 7590 tons of thrust a couple % is a lot of thrust. 

So if after a few launches anything like this turns out to be happening remember I said it first.   

[Starfox1701]

not likely Plasma tends to obey fluid dynamic principles so unless the outlets are polarized to setup some kind of projected containment the exhaust streams  should behave like fast moving streams of water when they encounter each other in a concentrated state. fortunately in a 0 pressure situation the plasma will quickly become low density limiting the opportunities for such interactions.

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Launch currently March 10th but this has changed many times before. 

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Just a piece of pure speculation on my part.

I wonder if having all these engines so close together they might constrain one another's exhaust like a large extension on the exhaust "bell" and increase the ISP and thrust by a small percentage.  When you are talking 7590 tons of thrust a couple % is a lot of thrust. 

So if after a few launches anything like this turns out to be happening remember I said it first.   

Apparently the sound was much less than expected.  I haven't seen any source speculate why - except me of course. 

My explanation is that the exhaust of the outer ring of engines blocks the sound of the inner engines escaping to the sides (only down).  Also of course the sound from those engines that goes towards the next engine in the ring or inwards is also blocked from escape.

These sound waves could be the constraining factor in the prior post.  Doesn't need a polarized plasma.

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It is apparently being rumored that ULA is for sale and that they hope to sell it this year.  Lots of confidence at the company for the success of Vulcan Centaur obviously.