BFR Developments

**Yazata** · Sep 16, 2020 03:45 AM

Tuesday Spt 15, 9:44 PM CDT - Tank is pressed. Venting heavily and frosted.

https://www.youtube-nocookie.com/embed/Ky5l9ZxsG9M

**Yazata** · (This post was last modified: Sep 22, 2020 04:00 AM by Yazata.)

Sept 21, 10:00 PM CDT. Another pressure test for 7.1. Maybe tonight they will finally pop it.

https://www.youtube-nocookie.com/embed/Ky5l9ZxsG9M

**Yazata** · (This post was last modified: Sep 23, 2020 08:48 PM by Yazata.)

Wednesday morning September 23: They finally succeeded in making 7.1 fail. Given the days it took them to make 7.1 burst, they must have gotten lots of data from it.

https://twitter.com/NASASpaceflight/stat...7713705984

It would be interesting to know what pressure it finally reached. I'm guessing that Elon and the SpaceX engineers will be satisfied with 7.1's performance. It looked to my layman's eye like a pretty successful pressure vessel.

The ultimate rupture appeared to happen around the circumference of the top dome weld.

https://www.youtube-nocookie.com/embed/CkFFgngw6Q4

**Yazata** · (This post was last modified: Sep 24, 2020 05:08 AM by Yazata.)

Mary has photographed SN8 outside the Midbay with its fins attached. These fins are the real deal, they were observed moving today as their actuators were put through some tests.

https://twitter.com/NASASpaceflight/stat...2602998784

Given the aerodynamic forces that they will experience, it will take a lot of force to move them. Reportedly that's supplied by multiple Tesla drive motors and power trains. (Word is that somebody at SpaceX knows somebody at Tesla...) Still unclear where all that is located, whether it's in the fin-root fairings (not much space) or inside the aft engine bay skirt. Electric power to drive it comes from (you guessed it) Tesla automotive batteries. They can be seen up on top of this SN8 tank section, the boxy thing on the left atop the upper pressure dome. It can't be seen in this photo, but that's where most of the electronics is too, the flight computer, the command and telemetry radios etc, tucked down between the dome and the top ring. Today's electronics isn't very big, Starship's is little boxes with lots of cables.

And in additional news, Mary has spotted the first identifiable piece of the first Superheavy booster. It was a ring barrel with a taped-on label that identified it as the Superheavy's sleeved common dome. So Superheavy pieces are starting to appear. It's expected that they will be stacked in the new High Bay.

Photo by Mary ('Bocachicagal') from twitter:

[Image: EinhRSSXgAAEsj3?format=jpg&name=large]

**Yazata** · (This post was last modified: Sep 26, 2020 06:52 AM by Yazata.)

According to the Boca Chica road closures, SN8 is scheduled to move to the launch site tomorrow (Saturday Sept 26) between 7 and 8 AM CDT.

Then cryo pressure tests are on for Tuesday Sept 29 between 9 PM CDT and 6 AM the next morning. (With Wednesday and Thursday as backup days.)

https://www.cameroncounty.us/wp-content/....29.20.pdf

Presumably if it passes the cryo proof test, the nose and three engines will be installed. Don't know if it will return to the build area for nose installation.

There will be one and maybe two static fires, then the long awaited 20 km test flight to try out the Crazy Elon landing maneuver.

Things are moving right along at a pace that seems slow by Science Fiction movie standards, but is super-fast by legacy-space standards. Reminds me of the wild-and-crazy 1960's when we went from the very first Sputnik satellite (1957) to landing men on the Moon (1969).

(Sep 5, 2020 03:39 AM)Yazata Wrote: SpaceX has just announced that the first Raptor Vacuum Engine has been completed and shipped to Texas for testing on the McGregor test stands.

And here's a video that appears to show the R-vac engine running at McGregor. I don't know how this guy got what looks like an internal SpaceX video. Maybe SpaceX released it somewhere or Elon tweeted it.

Edit I just stumbled on the video's source. It was posted to SpaceX's twitter page here:

https://twitter.com/SpaceX/status/1309317126130339845

The NSF engineers were exclaiming about its really fast ignition start-up. I assume that applies to the sea-level Raptors too, since they use the same power-head. That's going to be important on the 20 km flight when they will be shutting the engines off in flight, then relighting them for landing. (If they are reluctant to relight, big problems.)

https://www.youtube-nocookie.com/embed/sQdFJmqdjKE

**Yazata** · (This post was last modified: Sep 26, 2020 04:26 AM by Yazata.)

Very good aerial photo of SN8 taken yesterday from a Cessna by RGV Aerial Photography (who do weekly flybys) showing how its fins fold against its body. The little humans on the ground, in the lift and up on top all provide scale. The sibling in the Midbay is SN9. You can see what appears to be its concave common dome.

RGV Aerial Photography are well worth following on twitter. Lots of very good Boca Chica content from a different perspective.

https://twitter.com/RGVaerialphotos

[Image: Eixt36RWAAEBnAr?format=jpg&name=large]

Earlier today (9-25) RGV Aerial Photography posted the photo below on twitter with the caption "Nose Cone Zone. What caliber are these?"

And Elon replied ~9007 mm That should impress even Texans. (And they thought that their wimpy little 9 mm's were bad ass....)

Note two fins just to the left of the three nosecones. Presumably those are the nose fins/canards that will soon be mated with one of the cones in order to complete SN8's missing nose. Only problem is that none of the four visible cones have the fittings to which the fins will attach. So maybe SN8's future nose is still inside the Nosecone fabrication facility (the third shorter Giant Tent).

Another interesting thing are the circular concentric circle things up at the top of the photo. These appear to be pressure dome fabrication jigs. They aren't part of a Starship but rather part of making Starships. The fact that they are proliferating suggests that Elon's really gearing up to mass-produce giant spaceships.

The thing to the right of the yellow crane next to the second Giant Tent appears to be a new sleeved Starship thrust dome.

[Image: EiyeZi2XgAATSx8?format=jpg&name=4096x4096]

**Yazata** · (This post was last modified: Sep 27, 2020 03:39 AM by Yazata.)

SN8 is down at the launch area, waiting to be lifted onto the test stand

Elon tweets!

Nosecone & front flaps next week. SN9 next month

First flight is to 15 km or ~50,000 ft

https://twitter.com/elonmusk/status/1309909732954533889

We just need enough height to test body flaps & drawing propellant from headers vs main tanks. Will do several flights to confirm working well, then add heat shield & go high Mach.

https://twitter.com/elonmusk/status/1309912233921531905

Yes, the flaps are now directly driven by electric motors with a gearbox! No more hydraulics.

https://twitter.com/elonmusk/status/1309943983733272576

And the 7.1 results

8 bar differential in ullage, 9 bar at base due to propellant head. It's enough. Improvements in work.

https://twitter.com/elonmusk/status/1309915379041402881

Details on steel alloys in 7.1 and where the final rupture happened

Mostly 304L, some 301. Broke at 301 to 304 interface. SN9 will be all 304. Also, we're making some tweaks to the 304 alloy mixture.

https://twitter.com/elonmusk/status/1309916454616145920

Some explanation on what the '301' and '304L' numbers mean here

https://en.wikipedia.org/wiki/SAE_steel_grades

Photo from Elon

[Image: Ei279UbUYAAHzlj?format=jpg&name=large]

**Yazata** · (This post was last modified: Oct 4, 2020 01:45 AM by Yazata.)

RGV Aerial Photography's excellent flyover video of both the build site and the launch site, with helpful labels. Shot 9-24.

A couple of new things visible visible in this video are

1. a tapering ring that looks like part of a nosecone at about the 2:10 mark bearing what look like attachment points for nose flaps.

2. a large white horizontal tank at the landing pad that may or may not be intended for detanking landed vehicles.

Things that have happened since the video was shot. Even on days when nothing big is happening, Boca Chica is a hive of activity.

1. SN8 has moved to Launch mount A.

2. Multiple new ring barrels have been disgorged from the Giant Tents intended both for the new SuperHeavy and for SN's up to #11.

3. New domes have appeared from the Giant Tents destined for same. Some have been sleeved by the barrels.

4. Another large horizontal white tank has been added to the tank farm as it increases its capacity. Positioned next to the longer one visible in the video and similar in size.

5. SN9, whose common dome is visible in the video, has been capped by the rest of the CH4 tank and the top dome.

6. SN9's thrust section is in the Midbay and the rest of SN9's tank section will be stacked atop it soon

7. SN5 and 6 were sheltering in the new almost-completed High Bay due to an oncoming tropical storm which veered away. They are now out.

8. Concrete has been poured into at least four of the six legs of the new SuperHeavy launch mount. Still waiting to see what kind of platform is erected atop it.

9. The large red crane that was building the SuperHeavy launch mount is being disassembled and an even bigger new blue crane is being assembled. Not quite as big as Bluezilla, which is perhaps the biggest crawler crane available. But almost.

10. A Raptor engine was spotted being trucked away to parts unknown. May be one that powered SN5 or 6.

https://www.youtube-nocookie.com/embed/50xQpaBCoJw

**Yazata** · (This post was last modified: Oct 4, 2020 06:38 PM by Yazata.)

Tonight cryo pressure tests of the SN8 tanks are scheduled. Road closures on tap.

And last night the SN8 flaps were observed moving under their own power.

https://twitter.com/HughesMDflyer4/statu...9079246848

And back at the build area, SN9's tank section has been stacked

https://twitter.com/BocaChicaGal/status/...4533929986

**Yazata** · (This post was last modified: Oct 6, 2020 12:02 AM by Yazata.)

Here's RGV Aerial Photography's truly extraordinary October first flyover. Includes labels, stills and closeups of things that the brothers that own the company thought were significant. Photos taken by long lens from a Cessna. Shows the changes since the 9-24 video up above, their first in this format.

https://www.youtube-nocookie.com/embed/iEwaKeTwZ5M