Thread: SpaceX - On to Mars

Originally Posted by Edmond

The size of the thing!

That's what my missus said the first night we spend together!

Originally Posted by Edmond

The size of the thing!

It is just the second stage, they are always small. It looks big because it has the payload compartment on top. Volume slightly bigger than the volume of the ISS.

Of course the first stage is bigger.

Thank you. A very impressive display of excellence.

Mr. Musk and all on the project can rightfully get pats on their backs.

SpaceX are now planning on orbital launch very soon. They got a license for comms beginning June 20. These FCC licenses are easy to get though. FAA license for launch is harder and they still have to build a lot of ground support equipment. July or August seem to be very doable, landing and reuse are not part of the first launch. They need to convince FAA first that it is safe to let them fly to landing pads.

Meanwhile Jeff Bezos keeps pouring billions out of his own pocket into building a much smaller, much less capable system and is not advancing at all. There is proprietary info they have major setbacks.

A photo of one very important component of the SuperHeavy booster for Starship. It is the methane feed lines for the 28 Raptor engines driving the biggest booster ever.

Photo by BocaChicaGal. She used to be just a resident of the tiny Boca Chica village in the middle of nowhere. Then SpaceX moved there and she was asked to snap a few photos. Now she is an accredited journalist and world famous among space fans for her dedication. She provides photos and video coverage almost daily. When media professionals come for live reporting she does the camera work and the professionals don't interfere in what she does. They know she knows best and provides the best possible coverage.

From the picture above and other pictures we saw of the lower tank dome a fan made this graphic. It gives an idea how the 28 engines of the Starship Superheavy will be placed and fed with propellant. Looks like it is spot on. Very exciting for us fans.

Can even be seen as simple and straightforward. As far as any design with 28 engines can ever be simple.

About cost of these engines. The 28 engines will cost less than half of one of the 4 engines for NASA SLS. We can expect that the full stack of first and second stage of this Starship prototype with a total of 34 engines will cost less than one engine of SLS.

This is the third picture of this set. The Superheavy lower tank domes with the openings for propellant feed to the engines. The three pictures together give a quite clear impression how this works. If you spend a lot of time understanding and getting explanations.

Originally Posted by Takeovers

Can even be seen as simple and straightforward

hmm. The green pipes have been connected. There's another set of blue pipes somebody forgot. What are those for?

That's a lot of engines to ignite! How do they ignite them?

The blue pipes just connect to the dome in the third picture. To every second hole in that dome. They feed LOX, liquid oxygen, to the engines directly from the tank. The other half of the holes have the pipes connecting them to that central pipe from the fiirst picture bringing methane.

The engines are ignited by electric sparks. 3 separate points of ignition. One ignites a little methane on the LOX turbine pumping the LOX. One ignites methane with a little LOX on the Methane turbine. The third ignites the mix of LOX and Methane in the main combustion chamber. If the sequence of ignitions is only a little off you have a bad day. Full flow staged combustion engines are extremely tricky. There are good reasons why nobody has used them yet. Though the Soviets had a few on test stand but never made it to actual rockets. They have some advantages if they can be made to work. Like lower temperatures which makes them very robust even at the extreme power they produce.

They say, starting a rocket engine requires magic. Starting a full flow staged combustion engine requires black magic. Good thing that SpaceX had Tom Mueller, a renowned rocket engine wizard. Though he was only in an advisory function for Raptor. He did develop the Merlin engine that made SpaceX what they are today.

Though even back then Elon Musk made some cruicial decisions what exactly to develop. The story is that Tom Mueller made some suggestions what to do. Elon Musk did not like any of the options. So as a last resort he suggested one more option. Saying there are reasons why nobody ever tried this. If we do it we will blow up many engines on the test stand. But if we get it to work it will be a very robust and cost efficient engine. Elon said, this is what we will do. The result was the Merlin engine. But Raptor is again a class up, the best engine ever. Before when talking about engines he always praised the russian RD-180 engine as a top development, way ahead of Merlin.

Some update. Presently no more flight tests. They are working with top speed on completing the orbital launch mount. More flight tests would only cause delays in the working schedule.

The integration tower, on the right, is nearing its full height. One more segment and the crane to go up. Hook height of that crane will need to be 140m. 120m high Starship stack plus the launch pad below. Photo from yesterday evening. I have cut it out from a LabPadre live stream.



On the left, the first booster, 70m high on a test stand, tank tests, pressure tests, maybe a static fire coming. This booster had been intended to do the first orbital flight. But they have changed their mind on that. It is now downgraded to a test vehicle. The next one to build will be for the first orbital flight, together with Starship 20.

Time for the first orbital flight is presently August this year, but likely to slip. Both due to the complexity of work still ahead and regulatory approval by the FAA. The plan is for Starship to reach orbit but then deorbit near Hawail in a military test area, so 3 quarters of an orbit completed. Though for reasons uncomprehendable to me many people in forums insist it is not going to be orbital, just near orbital. BTW the first manned orbital flight by Yuri Gagarin was the same. He was orbital but his flight terminated with a deorbit burn before he completed a full orbit.

At the center of the picture the tank farm. Built by SpaceX, not some company specializing in cryo tanks. After all rockets are mostly cryo tanks, so SpaceX has the experience. Tanks this size have a long lead time and purchasing them would have to be done way back. Also SpaceX is aiming to build their rockets cheap so the tanks will be cheap too.


SpaceX requested environmental approval for building a second, identical launch pad right beside this one. It would require filling up some protected wetlands so not clear they will get the approval.

SpaceX are getting ready to launch the first orbital stack of Starship. Starship 20 is getting fully tiled. Including the flaps that are to steer and control attitude during reentry from orbital speed.

Entry is quite similar to what the Shuttle did. Attitude control is very different with the flaps.

The plan is to launch at Boca Chica, Texas, let Starship fly at orbital speed ~3/4 around the Earth and touch down in an airforce range near Hawaii. Far enough from any inhabited areas to cause no danger even with catastrophic failure. The booster is to send off Starship and then return to the launch site. Just ~50km short and dip into the sea, again for safety reasons. If they hit the target point close enough, they can then attempt landing and recovery of both stages on one of the next attempts.

They say chance for success on first try is low, but they like to downplay success chance.

The biggest obstacle is the FAA. Unclear if and when SpaceX gets permission. Worst case they don't or only with a very large delay. In that case they can complete building the launch pad in Florida at the Cape. There NASA is the responsible authority and they seem willing, even if it is out of pad LC-39A, which is the essential launch pad for their cargo and crew ships to the ISS.

Those tiles look amazing. SpaceX have spent a lot of engineering for these tiles and how they are fastened to the rocket body. Tiling the Shuttle was insanely complex and expensive. For Starship build cost is planned to be very low, even with high reuse in mind.

Thanks for the update.

The tiles in the top picture, on the rocket body, appear to be of three materials/layers. There are "spikes" on the rocket body, are they for location?. How are the tiles fixed, glued?

The tiles in the bottom picture, on the (steering flaps?), appear to be one material/layer. Are there "spikes" on the ??? for location?. How are they fixed, glued?

Are the tiles materials the same as the shuttle, or are they using new materials?

If tiles are damaged/fall off, do they remove/clear one tile or say a five tile square area?

Originally Posted by OhOh

Thanks for the update.

The tiles in the top picture, on the rocket body, appear to be of three materials/layers. There are "spikes" on the rocket body, are they for location?. How are the tiles fixed, glued?

The tiles in the bottom picture, on the (steering flaps?), appear to be one material/layer. Are there "spikes" on the ??? for location?. How are they fixed, glued?

Are the tiles materials the same as the shuttle, or are they using new materials?

If tiles are damaged/fall off, do they remove/clear one tile or say a five tile square area?

I was thinking of the 3 layers. Maybe an optical illusion, reflection, shadow, whatever. For sure there are 2 layers. On top the ceramic heat shield tile, below a white mat of flexible fiber, similar in heat resistance but no strength. It shields the tile from vibration of the body.

The mat is just pressed to the body, so the pins peek through. The tiles clip on to the pins. To take one off, they need to destroy it, but then it is probably already damaged.

We have no official word on the material. But it is a more advanced material that the Shuttle tiles. SpaceX licensed NASA TUFROC material and probably worked on it to advance it in cost and manufacturability. They did the same with the heat shield material of Dragon. They licensed NASA Pica and developed it into PicaX, much cheaper, much easier to manufacture and more capable. Most importantly, NASA could produce only quite small Pica tiles. SpaceX developed a manufacturing process that allowed to make bigger tiles.

Most important is a fast and easy method to place the tiles. On the Shuttle they were glued on and it was a huge task for a whole team to replace one. Plus almost every single tile of the Shuttle was a unique piece, many thousands of shapes. Steel can stand more heat than the Shuttle skin, so they can use thinner tiles and no glue, because glue would melt on these temperatures. Also too much work using glue.

Thanks.

Last night they successfully static fired a booster for the first times. 3 of 28 engines installed. Elon Musk tweeted they may go up to 9 engines, but I have my doubts. They will do static fires on the new orbital test stand with more engines, up to the full 28 engines. They intend to increase that number soon to 33 engines.

A twitter link, because it has just the short sequence of the fire itself in a loop. Not the hours waiting for it. Use sound on.


https://twitter.com/NASASpaceflight/...74652678922246

A big milestone. Successful at first attempt, though with a few minutes delay.

Bezos is about to lift off.

Originally Posted by helge

Bezos is about to lift off.

keep your fingers crossed and wish him a long stay up there

There is a rumor, that SpaceX is preparing a huge push to get things done in Boca Chica. For something major on August 5. August 4 is the day the ruling on protests about the lunar landing system is due. I am sure there is a connection. I had reported that NASA awarded the lunar lander system to SpaceX, using a variant of their Starship, which is designed to get people to Mars. It is widely expected the protests will be dismissed and work on the lunar lander can resume. SpaceX intends to hit the ground running.

They have send at least 300 highly skillled staff from Hawthorne in Los Angeles and from Florida to help out.

What happened today.

The last piece of the launch tower was lifted today, a total height of ~140m. Though how it will exactly work is not yet clear to us observers.

They seem to have a little trouble. After 5 hours they still work to finally fit the top section on.

The tower is just one of several activities today. We have been waiting for the orbital launch mount table to be finished and sent to the launch site. Today it finally happened and a tank for the tank farm went along. It is extremely massive and complex. They have worked on it at the factory site for at least half a year continuously. It needs to make all the connections to the Starship booster and needs to support the fully tanked weight of ~5000t liquid oxygen and methane.

The tank farm will have 7 tanks of that size, 9m diameter plus a 12m water tank for the cooling water needed at launch, so the engines don't destroy the launch pad and also to reduce noise.

A series of photos of B4, the first booster of Starship that is intended to reach orbit. All aboujt the powerhouse, the engine section.

All 29 engines mounted. Some of them are fillers at this time, not flightworthy, but most are. An outer ring of 20 engines, inner ring of 8 engines, center engine.

For comparison the engine section of the Soviet N1, which was supposed to get people to the moon but did never have a successful flight.

The bare thrust dome

A very special view from an airplane passing over the build site. the thrust dome from above. Workers installing the pipes that feed methane to the engines. If you look closely you see 17 workers installing the piping. That gives you an idea of the size. 17 workers and it is not crowded. Ordinary construction scaffolding and wooden planks. It is the inside of the thrust dome in the picture above, turned upside down.

The methane distribution pipes, this piece is in the center of the picture above, with the long pipes added.

Damn, just the size of it. About 25 years ago I took my mom and wife to the Johnson Space Center in Houston. They have an Atlas 5 on display, this thing is way bigger.