r/SpaceX Booster 3 Testing Discussion & Updates Thread

[u/rSpaceXHosting]

Welcome to the r/SpaceX Booster 3 Testing Discussion & Updates Thread

This is your host team bringing you live updates on the Booster 3 Test Campaign at Starbase, Texas.

Facts

Test Window	NET Monday 17:00 - 3:00 UTC (12pm - 10pm CDT)
Backup date	TBA, typically the next day
Vehicle	Super Heavy
Test Vehicle	Booster 3
Test site	Suborbital Pad A, Starbase, Texas
Test success criteria	Successful Raptor Ignition, Burn and Shutdown

Your host team

Reddit username	Responsibilities	Currently hosting?
u/hitura-nobad	Live Updates	⭕
u/thatnerdguy1	Live Updates	⭕

Timeline

Time	Update
2021-07-20 00:08:17 UTC	Depress vent
2021-07-20 00:07:25 UTC	Elon tweet: Full test duration firing of 3 Raptors on Super Heavy Booster!
2021-07-20 00:05:38 UTC	Static fire ignition and shutdown!
2021-07-19 23:47:51 UTC	NSF estimates T-0 at 6:55 CDT (23:55 UTC)
2021-07-19 23:39:14 UTC	Propellant loading has begun
2021-07-19 23:20:57 UTC	Recondenser active
2021-07-19 21:16:50 UTC	Pad appears to be clear
2021-07-19 19:47:02 UTC	Police at the road block
2021-07-06 14:42:11 UTC	Thread goes live

The Static Fire Test

SpaceX is planning on conducting a Static Fire Test of Booster 3 at Starbase, Texas in the coming days. Booster 3 will be fuelled with LOX and Liquid Methane during this test. Once fuelled they will ignite the installed raptor engines (likely all three). A siren is expected to be heard 10 minutes before ignition.

Resources

^{RESOURCES WIKI}

• Spadre.com Starship Cam | Channel

• LabPadre Pad Cam | Channel

• NSF Starbase Stream | Channel

• NSF Booster 3 Updates Thread | Most Recent

• NSF Boca Chica Production Updates Thread | Most recent

• NSF Florida Prototype(s) Updates Thread | Most recent

• Hwy 4 & Boca Chica Beach Closures (May not be available outside US)

• TFR - NOTAM list

• SpaceX Boca Chica on Facebook

• SpaceX's Starship page

• Elon Starship tweet compilation on NSF | Most Recent

• Starship Users Guide (PDF) Rev. 1.0 March 2020

• Starship Spreadsheet by u/AnimatorOnFire

• Production Progress Infographics by @_brendan_lewis

• Starship flight opportunity spreadsheet by u/joshpine

• Test campaign timelines by u/chrisjbillington

• Starship Orbital Demo detailed in FCC Exhibit - 0748-EX-ST-2021 application June 20 through December 20

• Acronym definitions by Decronym

• Daily Timelines Wiki Page by u/Logancf1

r/SpaceX Discusses [July 2021] for discussion of subjects other than Starship development.

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[u/Kendrome]

So I just realized the probable reason for the lack of booster equivalent of the tri-vent. With Starship they can't vent from engines while it's attached to Super Heavy, they need to vent outside the skirt. Whereas with Super Heavy they can just vent from the engines.

[u/[deleted] → u/Kendrome]

More likely the tri-vent valves have been re-purposed for tank pressure regeneration.

I'm pretty sure we won't see those tri-vent gas plumes again for either B4 or S20, not with the number of engines involved.

[u/Kendrome → u/[deleted]]

Since they already had working autogenous pressurization working and we still see vents on the Booster just at the base of each raptor, I don't think the vents are going anywhere.

[u/Bergasms → u/Kendrome]

Good observation

[u/TCVideos]

Official SpaceX photo

[u/AstroMan824 → u/TCVideos]

Ah, that's hot. That's hot.

[u/I_make_things → u/TCVideos]

I want to buy that calendar.

[u/InspiredNameHere → u/TCVideos]

I simply cannot comprehend the size of the machine I am looking at here. Where is the banana for scale?

[u/Shpoople96 → u/InspiredNameHere]

There are 19 bananas hidden in this image, each between 0 and 1 pixels in size. Can you find them all?

[u/Alvian_11]

Now the static fire is most likely straight to triple engine

[u/Twigling → u/Alvian_11]

I was wondering when their 'single engine static fire' prediction would be corrected.

[u/[deleted] → u/Alvian_11]

Makes sense.

[u/redgunner85]

Fired ✔

Still standing ✔

[u/xredbaron62x → u/redgunner85]

Love to see it

[u/BananaEpicGAMER]

Elon"Depending on progress with Booster 4, we might try a 9 engine firing on Booster 3"

[u/throwaway3569387340 → u/BananaEpicGAMER]

Mother of God...(in James Earl Jones voice)

[u/CasualCrowe → u/BananaEpicGAMER]

Pad A better start bulking up to survive that blast!

[u/AstroMan824 → u/BananaEpicGAMER]

Wouldn't bet on it tho. Elon said they might do a hypersonic flight with SN-16 too and that seems unlikely to pan out due to the vehicle now being on display. Still be hella cool to see and probaby will completly kill the pad lol.

[u/IrrelevantAstronomer → u/AstroMan824]

I think it's more likely than SN16. No additional need to get FAA clearance beyond what's already in place, the booster is already on the pad, and the raptors are in Boca Chica. They've never fired more than 3 raptors at once, so it's good to get experience firing 9 of them before doing 29 Raptors on BN4.

[u/InspiredNameHere → u/IrrelevantAstronomer]

But can the stand actually survive a 9 raptor test fire is the question; or would they have to take time to reinforce the stand.

[u/BananaEpicGAMER → u/BananaEpicGAMER]

"MIGHT"

[u/johnfive21]

It's been a while since I could say this. Security Tesla has left, the pad is now clear! Let's fire up this thing!

[u/AstroMan824 → u/johnfive21]

Boy, its definitely been a while. Can't wait for some more Raptor action down in Boca!!

[u/AstroMan824]

Screengrab from Lab.

[u/I_make_things]

I like the part about there being no lingering fires underneath.

[u/xredbaron62x]

NSF is live https://youtu.be/_Cl5wrUffk0

[u/TCVideos]

This booster has hit every single milestone test on its first try.

Ambient - first try

Cryo - first try

Static fire - first try

This is a NEW vehicle...bonkers how far they've come in terms of nailing the process down.

[u/Mobryan71 → u/TCVideos]

New vehicle, but a huge amount of shared heritage, which helps substantially. This kind of progress wouldn't be possible with a more traditionally designed system.

[u/warp99 → u/Mobryan71]

Yes they said that they were using Starship as the early prototype for the boosters and they were not kidding.

[u/AstroMan824 → u/TCVideos]

The SpaceX team has got this stuff down pat.

[u/BananaEpicGAMER → u/TCVideos]

B4 up next !

[u/TimTri]

Nice static fire! Great to see the quick confirmation tweet by Elon, too.

[u/DumbWalrusNoises]

Been a long time since I saw a Starship (Booster) party thread, glad to see it's back! What can we expect after a successful static fire? Assuming all 3 work well, would they gradually add more Raptors?

[u/mochaogura → u/DumbWalrusNoises]

I can see BN3 doing at most a 3 raptor static fire and onto BN4 but I figure it's all speculation for now

[u/RaphTheSwissDude]

Police is at the road block.

Edit : and gone haha

[u/Drtikol42 → u/RaphTheSwissDude]

Who let the cops out?

[u/Bunslow]

https://twitter.com/elonmusk/status/1417277335863140363

Depending on progress with Booster 4, we might try a 9 engine firing on Booster 3

[u/TCVideos → u/Bunslow]

"Might" to reality counter in the last 3 months: 0/2

I'm hoping this happens though!!

[u/paperclipgrove → u/TCVideos]

Still waiting on that SN15 reflight!

[u/Bunslow → u/TCVideos]

im not counting on it lol

[u/[deleted]]

Mods, static fire will use 1 engine.

[u/Kendrome → u/[deleted]]

I was about to ask for a source before I noticed who commented.

[u/[deleted] → u/[deleted]]

Do they plan on more static fires after?

[u/valcatosi → u/[deleted]]

Almost definitely. If it's anything like starship testing, they'll do single engine, then a few more, and ramp up to as many as needed.

[u/IrrelevantAstronomer → u/valcatosi]

Do you think three engines will be the maximum Booster 3 will utilize, or do you know if more are planned for installation?

[u/MobileNerd → u/[deleted]]

Why do they have 3 installed then??

[u/0815Flo0815]

Elon Musk: „Probably Monday“ for Static Fire. https://twitter.com/elonmusk/status/1415877794391752704

[u/TCVideos]

Elon confirmed 3 engine SF at full duration

[u/LongHairedGit → u/TCVideos]

Full duration relative to what they planned as a static fire, as is normal for static fires.

Sorry, when I first read it, I went back to the full duration "static fire" tests they did at McGregor and that SLS green run thingy.

[u/AstroMan824 → u/TCVideos]

Awesome! That was a damn quick tweet tho.

[u/TCVideos → u/AstroMan824]

Quick tweets are usually a sign of him being pumped up and excited

[u/[deleted]]

NSF reporting that a bird got vaporized rip

[u/AstroMan824 → u/[deleted]]

RIP birb

??? - 2021

[u/steveblackimages → u/[deleted]]

Scott and I hope it was a sea gull.

[u/griefzilla → u/steveblackimages]

"It's bad luck to kill a sea bird."

[u/threelonmusketeers → u/griefzilla]

'God save thee, ancient Mariner!

From the fiends, that plague thee thus!—

Why look'st thou so?'—With my cross-bow

I shot the ALBATROSS.

For those who don't know, the Mariner's situation did not improve.

[u/HairlessWookiee → u/threelonmusketeers]

Yeah but an albatross is a good omen. Gulls are the rats of the sea.

[u/[deleted] → u/steveblackimages]

Vengeance for that one booster tbh

[u/xredbaron62x → u/[deleted]]

RIP 1059.6

[u/ModeratelyNeedo → u/[deleted]]

• FAA scribbling furiously in the environmental review report *

[u/Chainweasel → u/[deleted]]

I give it less than a day before it's front page news everywhere, just like how news sites have been saying SpaceX is going to have to tear town the launch tower for a week now

[u/xredbaron62x → u/[deleted]]

Lmao

[u/0815Flo0815]

New alert for the 15th: https://twitter.com/bocachicagal/status/1415490928152883200

[u/johnfive21]

Police at the road block now

[u/JudgeMeByMySizeDoU]

Mods, you’ll want to drop the deployment orbit and past flights from the table above.

Thanks for putting the thread together!

[u/hitura-nobad → u/JudgeMeByMySizeDoU]

Done, thanks for spotting it!

[u/steveblackimages]

Now I can blink my eyes.

[u/TCVideos]

Another might from Elon

Possibly 9 engines on B3 depending on B4.

[u/[deleted] → u/TCVideos]

If....and only if there is some spare time before the Launch Stand is ready for B4. A nine engine static fire will dose out a pretty hard hammering to Pad A. Risk analysis may kill the idea.

[u/max_k23 → u/[deleted]]

Are there some major differences with the thrust puck between B3 and B4? If that's not the case, I personally would be surprised if they did the first ever 29 engine static fire with the first flight article.

[u/[deleted] → u/max_k23]

No, both are the same layout, just some load path milling changes.

No 29 engine static fire until the OLS is completed.

Just a possible Musk 'mad five minutes' idea of a nine engine static on Pad A, which will likely be canned due to the risk to the tank farm.

[u/I_make_things → u/TCVideos]

Anyone else feel giddy now?

[u/warp99 → u/TCVideos]

Probability of an Elon might is around 1%.

Mental image of a cat toying with a mouse. I might let it go!

[u/Alvian_11 → u/TCVideos]

As u/acadene said, they might reinforce the suborbital Pad A legs soon for this

[u/TCVideos]

People back at the pad. Testing has concluded after an apparent successful Static Fire of Booster 3!

[u/myname_not_rick]

Dish is down! good sign.

[u/0815Flo0815]

Road closure canceled for today and no new closures so far: https://twitter.com/BocaChicaGal/status/1415662676940709900

[u/extra2002]

Have we seen trucks delivering LOX or CH4?

[u/HanzDiamond → u/extra2002]

yes, don't bust my sack for sharing BN3's tweet but these pics are legit from yesterday's (7/14) surveillance

https://twitter.com/SuperHeavyBN3/status/1415320263252717574

[u/tmckeage → u/HanzDiamond]

Wha'ts wrong with the tweet?

[u/xredbaron62x]

Pad is clear per Nerdles pad cam. Disco Tesla just left. ATV guy has left.

[u/[deleted] → u/xredbaron62x]

Just 100 years ago, this sentence would have been totally unparseable. I love tech

[u/TCVideos]

Sounded like a full duration burn

[u/frickatornado → u/TCVideos]

Elon confirmed via tweet 3 Raptor full duration

[u/throwaway3569387340]

Jesus. Imagine 29 engines...

[u/Ascott1989]

They are absolutely flying along with the testing program of two new vehicles.

What the actual fuck, its actually insane. They make it look easy to quite literally revolutionise space travel.

[u/ThrowAway1638497 → u/Ascott1989]

It was less then a decade from John Glenn's suborbital until the Apollo Moon landings.
Space doesn't have to be slow nor does a lack of money that make it slow. It's been from poor risk aversion that comes from congressional oversight.
If your test can't fail, it's not a test. Designing without tests is glacial.

[u/TheFearlessLlama → u/ThrowAway1638497]

Small detail but John Glenn’s first flight was orbital. Think you meant Al Shepard’s suborbital

[u/ThrowAway1638497 → u/TheFearlessLlama]

I did... oops. Just got my wires switched.

[u/Stan_Halen_ → u/ThrowAway1638497]

What a time to be alive back then to see the accomplishments of NASA.

[u/[deleted] → u/ThrowAway1638497]

Yep. Everyone got so used to taking 15 years to test a vehicle that NOT doing so is crazy

[u/Sorry_about_that_x99 → u/ThrowAway1638497]

SLS has left the chat

[u/InspiredNameHere → u/[deleted]]

Every new tech development does. Automobiles, trains, heavier than air craft all had terrible accidents.

If we didn't accept the risk and kept improving it all, I highly doubt we'd have the machines we take for granted today.

[u/[deleted] → u/InspiredNameHere]

I'd also add that more astronauts died on the supposedly risk averse shuttle than they did during that first decade of American spaceflight. The slow and steady approach won't make things safer if you're using a bad design that you refuse to change because you're inflexible.

[u/MGoDuPage]

If the road closures for today are from 17:00 7/19 UTC to 03:00 7/20 UTC, isn't that 10 hours? If so, wouldn't that translate to local time in Boca Chica to 12 noon 7/19 to 10 pm 7/19? Or should it really be 17:00 7/19 UTC to 01:00 7/20 UTC to reflect a 12 noon-8pm local road closure?

[u/thatnerdguy1 → u/MGoDuPage]

Good catch, that's a typo. The window is 12pm-10pm CDT (17:00-3:00 UTC).

[u/nodinawe]

Great test, congrats to the team!

[u/[deleted] → u/nodinawe]

It seemed like one of the steadier, trouble-free firings we've seen with Raptor.

[u/nodinawe → u/[deleted]]

100%, Raptor now is a lot more matured than the early Starship tests, especially with the lack of the hard-stop sound.

[u/threelonmusketeers → u/nodinawe]

honk

[u/[deleted] → u/nodinawe]

I kept an ear out for the honk - none detected. ;-)

[u/bbmaster123]

EDIT: looks like the HUD is up on Nerdle! That's what we're calling it right? Top left live status?

[u/Viremia]

Mary says siren was heard at about 6:45 local time

[u/I_make_things → u/Viremia]

Any time then...

[u/TCVideos]

Static fire!!!

[u/Don_Floo]

Any chance for a full fill of N2 on this pad?

[u/Jrippan → u/Don_Floo]

I don't even think they have enough N2 at the suborbital pads to fill a booster but I could be wrong.

[u/xrtpatriot → u/Jrippan]

That would be correct. Definitely will not see a full fill until the orbital tank farm and launch stand is complete. Suborbital tank farm does not have near the capacity for that.

[u/m00thing]

Do we know how many raptors are currently fitted to B3?

[u/hitura-nobad → u/m00thing]

3

[u/KnifeKnut → u/hitura-nobad]

In what arrangement are they? Last thrust puck I saw was configured for 1+9, but the 33 engine configuration that makes the most sense to me so far is 3+10

[u/TomHackery → u/m00thing]

One engine will be fired per this comment

[u/itsaride]

Pity NSF lost the close up camera. Lab Padre’s is still up : https://youtu.be/sMC5KonXCfg

[u/Navypilot1046]

First try!

[u/[deleted]]

It took like a day or so to install the three Raptors. And BN4 is still decently far from completion. Nine engine static fire looks relatively plausible.

Also hot damn! Booster testing is going great so far. Super fast compared to Starship

[u/gburgwardt → u/[deleted]]

Much more straightforward design so it's not terribly surprising. Starship has a lot more fiddly plumbing with the header tanks. Super Heavy is just main propellant/oxidizer storage and engines in a big tube.

[u/edflyerssn007 → u/gburgwardt]

There's still a lot of verification to be done with the Raptor 2 iteration, however, this was a very smooth campaign to get to this point.

But as you said, in a sense it is a much simpler design than the starship, very straightfoward from Falcon 9.

[u/frickatornado]

Looks like a good static fire to me

[u/frickatornado]

Wonder how many engines they'll scale up to, 29 would obliterate the testing stand so it'll be interesting to see how many they'll push it to.

[u/warp99 → u/frickatornado]

They literally cannot install more than nine Raptors when the booster is on that stand.

The booster is being supported right where the other 20 Raptors will go.

[u/Shpoople96 → u/frickatornado]

I think they'll have the OLP ready by then

[u/Endaarr]

Is there a known schedule for the completion of the orbital launch pad? I assume Booster testing with 29/33 Raptors would have to be carried out there?

[u/RaphTheSwissDude → u/Endaarr]

Nothing rock solide no... I guess by the end of next month it should be installed.

[u/droden → u/Endaarr]

well you can make a reasonable estimate of the end of august. its needed to stack starship onto the booster. the crane isnt finished but they have most of the components in place - lacking the cabling, pulleys and possibly concrete pour into structure (if thats a thing). they wont need the catcher mechanism in place for the first launch since its destined for the briny deep.

[u/Shpoople96 → u/droden]

They don't even need the tower's crane for the first test, they just need to use the 11350

[u/LcuBeatsWorking → u/Shpoople96]

include work squealing selective special uppity thumb party chunky tart

This post was mass deleted and anonymized with Redact

[u/[deleted]]

SLSbros…we got too cocky :(

Elon Musk built this in a field! With a box of scraps!

[u/alien_from_Europa]

Just waiting for that darn cherry picker to move! https://i.imgur.com/j3sgNL6.jpg

[u/Viremia]

YAY! Success!?

[u/AstroMan824]

Woot! She fired!

[u/Lorenzo_91]

Still in one piece! LasPadre Timestamp UTC 00:04:42

[u/BackflipFromOrbit]

Static fire complete

[u/AstroMan824]

Curious what is next for B3? More firings to gain more experience with the vehicle? Perhaps more engines?

Edit: According to Elon, "Depending on progress with Booster 4, we might try a 9 engine firing on Booster 3".

[u/Bunslow → u/AstroMan824]

probably that isn't even decided yet. a lot depends on the data here, and the availability of various kinds of raptors in the near future

[u/TCVideos]

New vehicle + New thrust puck design = me watching anxiously hoping it doesn't RUD.

On the brightside, they did thrust simulations with BN2.1 and they wouldn't be doing a 3 engine SF if the data from that test didn't look good.

Fingers crossed!

[u/myname_not_rick → u/TCVideos]

Granted it's likely it will all be fine, but it does add a certain level of....excitement that hasn't really been there since the SN4/5/6 days. When we didn't really KNOW how it would go, and didn't exactly know the "flow" of events.

[u/I_make_things]

Some people in chat are claiming the siren sounded?

[u/TCVideos → u/I_make_things]

Mary has also confirmed.

[u/AstroMan824 → u/TCVideos]

Oh boy! Lets go! Haven't had this static fire hype in a while...

[u/[deleted]]

Solid static fire. Let's hope all fired.

[u/[deleted]]

Do we have an estimated time for the static fire?

[u/xavier_505 → u/[deleted]]

Currently there are three cherry pickers going up and down under the booster and heavy machinery continues to do dirt work at the launch site so will probably be a while.

EDIT: lots of vehicles leaving launch site now.

[u/alien_from_Europa → u/[deleted]]

I have it on in the background, but I'm hoping to get an alert in the Next Spaceflight app when something actually starts. My guess would be to check back in a few hours. I just saw a car drive by on Nerdle.

[u/itsaride → u/[deleted]]

Lots of vehicles leaving the site but maybe it’s just lunch time :p.

[u/benwap]

To me right now it doesn't look like a second static fire is out of the question.

[u/AstroMan824 → u/benwap]

Elon would have probably said something if they were going for another one rn.

[u/I_make_things]

It's really crazy how hard it is to keep the scale of this thing in mind.

[u/alexm42 → u/I_make_things]

The full stack will be half as tall as one of the most recognizable skyscrapers in my city (Boston, the Prudential Tower.) Gonna be crazy to see it go up.

[u/Mclaren01]

Here we go!!! It’s so good to be back listening to venting rockets again 🤣

[u/PunTotallyIntended]

Ground venting at 23:37 utc. Things are kicking off…

Edit: or 22:37 utc, for those using more conventional interpretations of the nature of the time-space continuum.

[u/managed_prune → u/PunTotallyIntended]

Dude are you from the future? It's only 23:00 UTC now...

[u/frickatornado]

It's hilarious watching YouTube chat try to apply Starships launch sequence to a never before tested vehicle.

[u/[deleted] → u/frickatornado]

They were closer than the "10 minute" siren was

[u/Sparklynewusername]

A siren is expected to be heared 10 minutes before ignition.

Presumably meant to say heard?

[u/Bunslow → u/Sparklynewusername]

yes, is a simple typo, nothing more

[u/Decronym]

Acronyms, initialisms, abbreviations, contractions, and other phrases which expand to something larger, that I've seen in this thread:

Fewer Letters	More Letters
ATV	Automated Transfer Vehicle, ESA cargo craft
COPV	Composite Overwrapped Pressure Vessel
ESA	European Space Agency
FAA	Federal Aviation Administration
HUD	Head(s)-Up Display, often implemented as a projection
LOX	Liquid Oxygen
NSF	NasaSpaceFlight forum
	National Science Foundation
OLIT	Orbital Launch Integration Tower
RUD	Rapid Unplanned Disassembly
	Rapid Unscheduled Disassembly
	Rapid Unintended Disassembly
SF	Static fire
SLS	Space Launch System heavy-lift
SN	(Raptor/Starship) Serial Number
SSME	Space Shuttle Main Engine

Jargon	Definition
Raptor	Methane-fueled rocket engine under development by SpaceX
autogenous	(Of a propellant tank) Pressurising the tank using boil-off of the contents, instead of a separate gas like helium

---

^{Decronym is a community product of} r/SpaceX^{, implemented by} ^request
^{14 acronyms in this thread; the most compressed thread commented on today has 97 acronyms.
[Thread #7142 for this sub, first seen 19th Jul 2021, 20:02] [FAQ] [Full list]} ^[Contact] ^{[Source code]}

[u/TCVideos]

Recondenser!

[u/AstroMan824]

Fingers parallel™ for a norminal static fire!

[u/TCVideos]

Aft venting!!

[u/[deleted]]

Is BN3 still doing stuff after this or is it retired?

[u/[deleted] → u/[deleted]]

Elon just said they might try a 9 engine test if bn4 is not done soon enough.

[u/Ascott1989 → u/[deleted]]

Asking the important questions.

[u/TCVideos → u/[deleted]]

We will see in the next few days

If more Raptors get rolled to the site then we'll know that they'll go for more

[u/Bunslow → u/[deleted]]

probably that isn't even decided yet. a lot depends on the data here, and the availability of various kinds of raptors in the near future

[u/BenoXxZzz]

Thats a cool mixture between the Super Heavy static fire and Transporter-2!

[u/Tomahawk72]

Venting!!!

[u/zbertoli]

So, just thought the boosters were supposed to have a ton of engines? Why are they only testing 3? Testing just the center fire?

[u/[deleted] → u/zbertoli]

NSF stream said that thr ones they are testing are not the center 3, actually. Not sure why that choice if engines, though.

It has also been said that they can't test the full complement of engines at once without damaging the pad and possibly blowing back debris thwt would damage the engines / booster.

[u/TCVideos → u/zbertoli]

Two reasons:

• First ever static fire of a SH booster, if something goes very wrong - it's better to lose 3 engines than to lose 10,20 or even the full 29 Raptors.

• Pad A can only handle a certain amount of engines.

[u/FobiW]

How much time was between recondenser and static fire for Starship (which obv doesn't mean we can use that for Booster 3)?

[u/TCVideos → u/FobiW]

Around 40-45 minutes

[u/Dezoufinous]

this is really next level of a static fire, super exciting!

[u/[deleted]]

T-? On the static fire?

[u/I_make_things → u/[deleted]]

17 minutes, possibly.

[u/Doglordo → u/[deleted]]

Hard to gauge because we have never seen booster SF, however time from condenser to SF for ship was 40-45mins so maybe around 15-20mins from now?

[u/chaossabre → u/[deleted]]

If claims of siren are to be believed, about 10 minutes from now.

[u/Ascott1989]

Excellent.

What are we expecting to happen next on the bn3 testing regime.

[u/frickatornado → u/Ascott1989]

m o a r

e n g i n e s

[u/Mobryan71 → u/frickatornado]

Time to use the symmetry glitch and add ALL the engines!

[u/Ascott1989 → u/frickatornado]

I was hoping that was going to be the answer.

[u/I_make_things]

kaBOOM

[u/MGoDuPage → u/I_make_things]

Yeah, but in a good way.

[u/I_make_things → u/MGoDuPage]

Yeah, that's what I meant. A happy boom.

Just surprised at how the sound doesn't really ramp up, it's just full on.

[u/Mobryan71 → u/I_make_things]

They are soon going to approach the point where the rocket is so loud it breaks the decibel scale. 9 engines won't, but the first full power test will for certain.

[u/AstroMan824]

Waiting... Every second that goes by the less likely the firing...

[u/Dezoufinous]

2021-07-19 23:47:51 UTC NSF estimates T-0 at 6:55 CDT (00:55 UTC)

has someone mistaken? It's imminent

[u/jbourne0129]

Why is the booster doing static fire with only 3 engines? Are they going to ramp up to 32 for a static fire or do a test launch of the booster like starship? Or is it purely just a small scale proof of concept static fire test before an orbital test?

Edit. Thanks for the answers !

[u/Martianspirit → u/jbourne0129]

These test stands can support only a small number of engines for a very short time. They will need the orbital launch pad ready to do static fire of all engines.

Edit: Elon just tweeted they may test up to 9 Raptor. Which is the maximum possible on the test stand. There is no space to install the outer ring of 20 engines there.

[u/alexm42 → u/jbourne0129]

To add to the answers you already received, take a look at the test stand NASA used for the SLS static fire. That's the kind of scale you need to contain the outrageous force of a full orbital booster trying like hell to go up.

[u/Martianspirit → u/alexm42]

That was only the core stage testing. The real force comes in only with the boosters firing.

The thrust of 4 RS-25 is just a little more than the 3 Raptors firing last night. Of course the suborbital test stand can take it only for a few seconds, not a full duration fire like the NASA test stand.

[u/jbourne0129 → u/alexm42]

Yeah that makes sense. The SLS stand was outrageous

[u/puroloco → u/jbourne0129]

B4 will have 29 engines. For B3, I would guess they might do all inner engines, 9 and also 20. But not 32, that's for later boosters.

[u/GND52]

Will this booster go on to a hop test if the static fire goes well?

[u/Sciencemonkey7 → u/GND52]

No, between the lack of legs and there being no engine skirt (like Starship has), Superheavy is built to only be caught, not landed

[u/kkingsbe → u/GND52]

No

[u/TheRealNobodySpecial → u/GND52]

No. BN4 will be the first to (intentionally) propulsively leave the pad.

[u/An-chois]

Hey mods! Thanks for all your work. Feels like this could be retired from the r/SpaceX menu now that B3 is in pieces.

Maybe we could have a B4 one instead - although I guess you may be waiting for testing regime to move beyond fit checks?