Scivillage.com Casual Discussion Science Forum

Photo by Austin Barnard that shows the blue cross outline but before the thruster pods (two of them) were installed immediately below it.  More of the small red tanks (an earlier one visible in the upper right) have been installed up on top. They are COPVs (composite overwrapped pressure vessels). The new ones have presumably been installed to supply pressurized gas for the thrusters.

Check out Austin's twitter page. He's a local Brownsville resident and posts interesting stuff.

https://twitter.com/austinbarnard45?lang=en



The watertower looks exceedingly crude, but it's actually constructed from some very sophisticated bits. (It's been called a Lego rocket.) When the new raptor engine arrives, it will be the most advanced rocket engine design to ever fly. (Assuming this thing succeeds in flying.) Full-flow staged-combustion. The first of these was the Russian Energomash RD 270 which underwent test-stand firings in the 1960's but was never flown. Aerojet-Rocketdyne experimented with one on a test stand around 2000, but never flew it. SpaceX is the third, the first to progress to an operational engine. The watertower's control system looks like it's from a Falcon 9, either new or maybe from one of the write-off boosters like that one that went into a spin because of a hydraulics failure and crashed into the sea. (With Elon smoking dope!)

Excellent short article from Teslarati with BCG's photographs about the recent mods to the watertower. The author notes that the attitude-control-system pods are apparently being installed on the watertower in three sets of two (because single thrusters wouldn't be strong enough for such a massive vehicle?), about 120 degrees apart around the vehicle's circumberence, with one of each pair an older model thruster no longer being installed on new production Falcons (but perhaps still in the SpaceX inventory in Hawthorne), while the other is a newer model thruster pod of the sort currently being installed in production block 5's. He speculates that the newer model thrusters come from B1050, the booster that went into a fatal spin and crashed into the ocean (immortalized in the little science fiction film earlier in the thread).

https://www.teslarati.com/spacex-prepare...ght-tests/

The author notes what an odd vehicle this is. Hopefully it will soon be doing spectacular things. Which will probably only include rising a few hundred meters on a pillar of flame, hovering and then descending again. But when it happens, it will look very cool on the live webcams.

The second StarHopper, currently under construction, might eventually ascend higher (perhaps all the way to space and back) in more like the flight plan for the current Falcon 9 boosters. Elon Musk has called it "orbital", but I don't really believe it. Even if it could reach orbit in SSTO (single-stage-to-orbit) fashion, a difficult proposition, it likely wouldn't have enough fuel left to perform its reentry and propulsive landing. So it would be stuck in orbit and Elon would essentially lose it unless he could refuel it up there. On the other hand, these BFR upper stages are supposed to return to Earth from orbital velocities and SpaceX will have to test the planned cooling system and prove the aerodynamics. It will be interesting to see how that unfolds.

Here's BCG's latest photo of the second StarHopper being assembled. Keep in mind the scale of this thing. It's about 30 feet/10 meters wide.

https://twitter.com/NASASpaceflight/stat...7918796800

(May 9, 2019 04:20 AM)Yazata Wrote: [ -> ]. . . When the new raptor engine arrives, it will be the most advanced rocket engine design to ever fly. (Assuming this thing succeeds in flying.) Full-flow staged-combustion. The first of these was the Russian Energomash RD 270 which underwent test-stand firings in the 1960's but was never flown. Aerojet-Rocketdyne experimented with one on a test stand around 2000, but never flew it. SpaceX is the third, the first to progress to an operational engine.

Apparently it's got be this type engine thanks to the future ambition of utilizing methane on Mars, rather than easier or less experimental effort to merely achieve shorter range goals/success. But at least this concept has gotten off of paper in the past and been physically realized to some extent. Makes it a little better off than the "transpirational cooling" method which Elon wants to supplement the hexagon-tile heatshield of Starship with. According to one source the idea has probably been around for over a half-century, but may have never had serious research and testing done on it anywhere/anytime.

(May 9, 2019 07:37 PM)Yazata Wrote: [ -> ]The author notes what an odd vehicle this is. Hopefully it will soon be doing spectacular things. Which will probably only include rising a few hundred meters on a pillar of flame, hovering and then descending again. But when it happens, it will look very cool on the live webcams.

Local news is reporting another round of SpaceX road closures on the Boca Chica beach road for May 28-30.

https://www.brownsvilleherald.com/news/l...e283c.html

If Elon's really going to make his promised big presentation on June 20 (at the AIAA in Dallas?) he's gonna want some spectacular video to show everyone.

But... if there's any truth to this scenario, we should be seeing a new engine arriving very soon. (From McGregor, where SN-03 has been undergoing tests? Nobody is sure where SN-02 is, the engine that was previously on the Watertower in April, so it might be the one returning.) The road closures are a tip-off. I expect to see the FAA announcing temporary flight restrictions too, but that hasn't happened as of today. Lots of eyes are going to be on BCG (including NASA and space industry professionals) since she is on-scene, watches everything, posts every day, and will probably be the first to publicly verify the arrival of the engine.

Here's the very-frustrated Watertower blowing off steam (talk about blue balls!) during the last test series around the beginning of April.

Unleash the Watertower! Let it loose!!

Elon says that engine SN4 is completed and Hawthorne is currently working on SN5. Emphasis now is increasing production rate for future engines. They hope to have manufactured a hundred of them by next year sometime.

https://twitter.com/elonmusk/status/1128450109052575744

They are going to need more engines, because the watertower business is taking off. (Literally!)

SpaceX has begun construction of yet another Starship prototype at their rapidly expanding Cape Canaveral facility at Cocoa FL! They have several locations in the Cape area, are building multiple new buildings and existing buildings have been leased. Lots of engineers, fabricators and welders are being being hired. The facilities aren't even completed and a vehicle is already under construction! (It's exactly what we saw in Texas.)

Elon verifies it and says that the Texas and Florida sites will be in competition with each other. Each site must share all its information with the other site, but the other site isn't obligated to do things the same way.

It's an extremely non-traditional way of doing things. The existing aerospace contractors must be getting apoplexy. It's what you get with crazy Elon in charge and not the bureaucratic and risk-averse US Government. I just hope that it doesn't lead to the teams cutting corners and taking unnecessary risks just to be first to some milestone, and getting people killed. It does remind me of Apollo to the Moon in the 1960's though.

https://twitter.com/NASASpaceflight/stat...4621751296

As one of the observers wrote: "I just got this odd frisson feel in my stomach/head. We have not one, not two, but three BFR prototypes being built." Couldn't agree more.

In more news, Elon says that the planned fins/aerodynamic-control-surfaces/landing-legs will begin being installed on the Boca Chica "orbital" prototype around the end of June. These should be very different than the landing legs on the first water tower, more like tail fins on an aircraft, but strong enough to support the entire fully-fueled structure.

Articles summarizing the same material

https://arstechnica.com/science/2019/05/...ip-builds/

https://www.teslarati.com/spacex-starshi...rototypes/

First photos of the new Starship under construction in Florida.



Video of a TV report from the same TV station here.

https://www.youtube.com/watch?time_conti...zqeSe3Q_zc

(May 9, 2019 07:37 PM)Yazata Wrote: [ -> ]The second StarHopper, currently under construction, might eventually ascend higher (perhaps all the way to space and back) in more like the flight plan for the current Falcon 9 boosters. Elon Musk has called it "orbital", but I don't really believe it. Even if it could reach orbit in SSTO (single-stage-to-orbit) fashion, a difficult proposition, it likely wouldn't have enough fuel left to perform its reentry and propulsive landing. So it would be stuck in orbit and Elon would essentially lose it unless he could refuel it up there.

Elon apparently agrees because he now says (regarding SSTO): "It technically could, but wouldn't have enough mass margin for a heat shield, landing propellant or legs, so not reusable".

https://twitter.com/elonmusk/status/1129629072097775616

It's interesting to watch how the Florida Starship prototype is being constructed. It's apparently being constructed from preformed steel rings, not from steel plates like in Boca Chica. The welds on the Florida version look better too.

The stack of Florida rings has reached five rings high, at last count. 20-30 feet (6-9 meters) high.

The Florida vehicle seems a lot better constructed and more aesthetic than the Boca Chica one. They seem to be learning from experience.

I'm guessing/speculating (that's all it is) that #1, the Watertower, might only end up going a few hundred meters high. It's more about reproducing the kind of landing control that they have with Falcon 9's with something much bigger and more massive. The #2 Boca Chica Starship prototype might only ascend a few thousand meters (~10,000 feet) and be used for testing multi-engine propulsive landings. And the #3 Florida one might end up being a full-scale suborbital spaceship that starts to explore re-entry (but still not from orbital velocities, a big challenge).

It will be interesting to see if they all work or if any are lost to accidents.

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BCG is on watch and reporting that LOX and LN2 (liquid nitrogen) are being delivered today. (LN2 is used to flush the system and to do pressurization tests.) The Watertower is a center of activity.

The most dramatic development is the arrival of some heavy duty hydraulic jacks yesterday and their use this morning to jack up the Watertower. At first it went up a few inches, then about four feet (1 meter +). All three landing legs are off the ground as we speak. Apparently they are going to be welding on better landing feet in preparation for actual flights. (A guess.) The Watertower is no longer tied down like it once was. Over the last few days they also seem to have been installing quick-disconnect fittings for the various hoses and cables that connect the Watertower to the ground. (Lots of talk about that. Will they just pull loose or will they be retracted so that the rocket blast doesn't cook them?)

But... it ain't going nowhere without a rocket engine and an engine hasn't been installed yet. It isn't even clear if an engine is on site. (Hard to know what's in all the trucks and shipping containers.)

(May 9, 2019 07:37 PM)Yazata Wrote: [ -> ]It's interesting to watch how the Florida Starship prototype is being constructed. It's apparently being constructed from preformed steel rings, not from steel plates like in Boca Chica. The welds on the Florida version look better too.

The stack of Florida rings has reached five rings high, at last count. 20-30 feet (6-9 meters) high.

The Florida vehicle seems a lot better constructed and more aesthetic than the Boca Chica one. They seem to be learning from experience.

Maybe it's the proximity of Cape Canaveral, but construction with rings seems to be how at least part of the Saturn moon rockets were constructed. This appears to be a drawing of the Saturn second stage, and to my layman's eye, it resembles what appears to be the Florida Starship contruction. Again to my non-expert eye, it looks much better than plates.

In Boca Chica, BCG reports that the Second Starship prototype has finally had its nose joined to the stack. Now that it has its pointy-end, it's starting to look like a spaceship.

https://twitter.com/BocaChicaGal/status/...0516101120

It's still lacking its base down at the bottom, including the load-bearing thrust structure upon which the engines will be fitted and the landing legs/control surfaces will be fitted. Elon says that the wings/legs should be coming around the end of June.

The hydraulic jacks have gone from the Watertower and BCG reveals that the vehicle has been given bright shiny shoes. (Texas: where if they can't shoe horses, they shoe rockets.)

https://twitter.com/NASASpaceflight/stat...0208474115

Speculation is that these are crushable shock-absorbers that presumably will have to be replaced each flight.

Still no sign of a Raptor engine for the Watertower which is scheduled to be doing something next week (28th through 30th), judging from the announced road closures. It seems to me that it will probably take some time to fit it and to test the gimbal actuator systems that will move it to vector its thrust so that it can balance and hover. Time's getting short.

Here's something interesting, an application to the FCC for temporary (24 months) permission to operate ground and air based radio communications for research purposes. There's interesting stuff for the geeks about frequencies and stuff, along with this tidbit that everyone will find interesting: "please note that transmitter/antenna is affixed to a VTVL vehicle (see Exhibits). The vehicle will fly vertically from the ground to under 500 meters for its low-altitude tests and up to 5000 m for its high altitude tests." So there's a bare outline of the plan for the initial tests. Apparently one or both vehicles will be doing both low and high tests over a period of up to two years, suggesting that we might see the one of them up to 10,000 feet high. (Which should look pretty spectacular.) I wish that I could find the exhibit that was apparently attached that no doubt lays it out in more detail.

https://apps.fcc.gov/oetcf/els/reports/4..._seq=93420