Space Flight Updates - Russia pullingout of ISS?
- Thread starter ThreatMatrix
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- Aug 28, 2014
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Amazing I know. It needs something like a 15 mile radius or it will break windows or worse.
The problem is that it has to launch over water. The FAA frowns on launch paths over land. But both the Cape and Boca Chica are too close to population centers.
The other problem is the need to launch as close to the equator as possible so as to be in the proper orbital inclination. Also the closer to the equator the more of a velocity boost it gets from the earth's rotation.
The Shuttle was freakin' loud. On a clear morning you could hear it in Orlando 50 miles away. SuperHeavy is supposedly much louder.
- Jul 16, 2018
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- Aug 28, 2014
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Since we last talked SN8 has gone through 3 nights of pressure and cryo testing. Locals have been bytching about SpaceX closing the beach access road so they've been running these tests in the wee hours of the morning.
In the next few days it should get three raptor engines installed. Then in unknown order static fire tests and a nosecone. The nosecone does contain a header tank that they will need to do a static fire with. We just don't know what will happen first.
Elon said we would see a high altitude launch this month. Assuming everything goes well it's possible. Amazing how fast they are moving.
As an example of how Elon works, Spacex is building the launch platform for the super heavy. Elon tweeted that it is being built without a flame trench and that may or may not be a mistake. NASA would have spent millions and years before they started construction. Elon says "build it, let's see what happens".
In the next few days it should get three raptor engines installed. Then in unknown order static fire tests and a nosecone. The nosecone does contain a header tank that they will need to do a static fire with. We just don't know what will happen first.
Elon said we would see a high altitude launch this month. Assuming everything goes well it's possible. Amazing how fast they are moving.
As an example of how Elon works, Spacex is building the launch platform for the super heavy. Elon tweeted that it is being built without a flame trench and that may or may not be a mistake. NASA would have spent millions and years before they started construction. Elon says "build it, let's see what happens".
- Aug 28, 2014
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Welp. They're building a Super Heavy launch pad at BC.
So they're going to launch test vehicles at least. They will have to be under powered obviously. Probably fewer engines. I think the full Super Heavy will have 28 engines though that number drops as they improve the engine.
Incidentally they rolled out 2 of the 3 engines for Starship SN8 this morning.
So those will get mounted soon and we should see test fires by next weekend. You can see a cone section in the background behind one of the buildings. That will be mounted on top after the static fire tests. It almost doubles the size of the StarShip.
Then SuperHeavy is even taller so once it's all stacked it's gonna be yuge!
The highbay in the background is where they will construct SuperHeavy (already underway). SuperHeavy will be put on the launch stand then Starship will be mounted on top of it.
So they're going to launch test vehicles at least. They will have to be under powered obviously. Probably fewer engines. I think the full Super Heavy will have 28 engines though that number drops as they improve the engine.
Incidentally they rolled out 2 of the 3 engines for Starship SN8 this morning.
So those will get mounted soon and we should see test fires by next weekend. You can see a cone section in the background behind one of the buildings. That will be mounted on top after the static fire tests. It almost doubles the size of the StarShip.
Then SuperHeavy is even taller so once it's all stacked it's gonna be yuge!
The highbay in the background is where they will construct SuperHeavy (already underway). SuperHeavy will be put on the launch stand then Starship will be mounted on top of it.
- Aug 28, 2014
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1st Raptor has already been installed. It's under the skirt, you can't see it. Second raptor is being prepared. Third raptor is somewhere.
- Aug 28, 2014
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If your curious this is a closeup of a Raptor. SpaceX is good about marking serial numbers on everything so this is SN39 and SN32 is already installed. Still on watch for third Raptor.
SpaceX builds the Engines in Hawthorn California then ships them to McGregor Texas where they are tested on a test stand then they are shipped to Boca Chica for integration. They need to build a shyt load of engines fast and are ramping up to turn out a few a week. A complete SuperHeavy/Starship has at least 34 engines and they are likely to crash as least one during testing.
SpaceX builds the Engines in Hawthorn California then ships them to McGregor Texas where they are tested on a test stand then they are shipped to Boca Chica for integration. They need to build a shyt load of engines fast and are ramping up to turn out a few a week. A complete SuperHeavy/Starship has at least 34 engines and they are likely to crash as least one during testing.
- Jun 11, 2014
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Founding Member
I'm getting a bad feeling about the BFR test series. I note, you mentioned they might lose 1 or 2 during test series, I hope the "cratering" doesn't have unforeseen consequences.
Elon has Brass Nuts!
Elon has Brass Nuts!
- Aug 28, 2014
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They'll crater over water. RUD (Rapid Unscheduled Disassembly) is not uncommon in rocket development. Thus the prohibition on launching over land. Worst case scenario is it happens on the pad because you destroy the pad. And SpaceX can build a rocket faster than a new pad.
When a Falcon 9 booster lands it aims for water. If everything is going perfectly it will, at the last possible second, aim for the pad. The first few times they didn't even try to land the Falcon 9 on a pad, they just put it down in the water. And there have been barge landing failures(in the beginning) where the booster just hit the water instead of destroying the barge.
StarShip will be trying a totally new method of reentry. It will fall belly first. The "fins" that you see on the StarShip are not for aerodynamics. They act as air brakes that keep StarShip in the belly down attitude during descent. At the last instant it will flip vertical and fire the engines to land. Being that this has never been done before it won't be surprising to not work the first time. SN8 will be testing this maneuver this month when it launches to an altitude of about 20 miles.They hope it will work the first time but are planning for it to not.
After SN8 the next ship (SN9) will have a heat shield and launch to a high enough altitude to test the heat shield.. Again this is a totally new type of heat shield so it might not work the first time. There are currently six StarShips under construction at Boca Chica so they have plenty in case they lose one. StarShips are really nothing more than stainless steel. Once they figure out how to weld them properly they get built pretty fast.
The engines are the expense and are complicated to build. Elon has said that engine production is one of the harder things they have to do.
A SuperHeavy is just a larger StarShip. They will have 5-10 StarShip launches under their belt before they try a SuperHeavy. So RUD on the pad isn't likely. However, when they stack it with a StarShip and try to go suborbital then orbital they may lose one. Musk has said it's 50/50.
TL : DR My concern isn't explosions it's Raptor production. They've built at least 39 this year but some have gone boom and some no doubt are sub optimal. If they lose a complete SH/SS they lose 30+ engines.
- Aug 28, 2014
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A Starlink mission launched another 60 satellites today. Succesfull booster landing and they caught one of the fairings.
Last Sunday SpaceX installed 3 engines on SN8 and then during the week they ran a wet dress rehearsal. Static Fire is scheduled for tonight. Then hopefully a nose cone this week.
The noise issue has been bothering me. The question is how few engines (to keep noise down) can you get away with and still make LEO.
So I ran some numbers and didn't check them but assuming 200t of thrust for each raptor and needing at least a TWR of 1.5 you'd need 18 engines to get 2400 tonnes off the ground. That would give you
SS Dry mass=120t; payload=0; propellant=280t; wet mass =400t; (dv= ~4500)
SH Dry mass=200t; payload=SS=400t;propellant=1800t; wet mass=2400t (dv= `5100)
Just enough dV for orbit.
Somebody else on reddit ran the numbers and got the same answer so that's what we're going with. Presumably that's few enough engines to launch from BC.
Last Sunday SpaceX installed 3 engines on SN8 and then during the week they ran a wet dress rehearsal. Static Fire is scheduled for tonight. Then hopefully a nose cone this week.
The noise issue has been bothering me. The question is how few engines (to keep noise down) can you get away with and still make LEO.
So I ran some numbers and didn't check them but assuming 200t of thrust for each raptor and needing at least a TWR of 1.5 you'd need 18 engines to get 2400 tonnes off the ground. That would give you
SS Dry mass=120t; payload=0; propellant=280t; wet mass =400t; (dv= ~4500)
SH Dry mass=200t; payload=SS=400t;propellant=1800t; wet mass=2400t (dv= `5100)
Just enough dV for orbit.
Somebody else on reddit ran the numbers and got the same answer so that's what we're going with. Presumably that's few enough engines to launch from BC.
- Aug 28, 2014
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Preburner test last night. So that's all the way up to lighting the engine. Still hoping for static fire tonight. This looks different. Low on the body you can see lox venting. When they tested only one engine there was only one vent but now that they're firing three there are three vents.
The nosecone has been stacked on it's barrel section and is now ready to stacked on SN8.
The nosecone has been stacked on it's barrel section and is now ready to stacked on SN8.
- Aug 28, 2014
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Notice that right before firing one of the LOX vents suddenly spews a strong stream of gas.
So Static Fire is done. Now we wait. Will they do some more tests or will the Nose Cone go on? We will know in a day or two.
So Static Fire is done. Now we wait. Will they do some more tests or will the Nose Cone go on? We will know in a day or two.
- Aug 28, 2014
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Nose cone rolling out to launchpad for stacking. Maybe as soon as tonight. The large white crane was moved out there earlier to day.
