SpaceX Starship tests: SN15 flight early May

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TL;DR Summary

Testing has moved on. Original summary: SpaceX plans to fly a Starship prototype to a height of 150 meters on July 13 or the following days

SpaceX doesn't have a public test plan, but they need to close a public road to fire the engines, and road closures need to be announced in advance - including their reason. In the next days SpaceX plans a static fire (engine fires but the spacecraft is fixed to the ground), and Monday next week (the following days are backup dates) they plan to fly up to 150 meters high. Tweet. As usual: The test might get delayed, cancelled, or the vehicle might disintegrate before. If not, we can get the first free flight of a "real" Starship prototype. Starhopper flew to 150 meters before but it was a much more primitive prototype - walls so thick that it would never make it to space, for example. SN5 doesn't have the payload section attached but that is largely more of the same and it doesn't need to withstand the high pressure the tanks have.

Edit: Cancelled for now. They are working on the hardware.

Edit 2: Maybe with one week delay (Week of 20-26).

 

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Not sure if the embedding works. It's a tweet by Musk:
Will attempt to fly later this week

 

[gleem]

The successful static fire of SN5 just completed.

 

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Here is a video

Starship SN5 just completed full duration static fire. 150m hop soon.

 

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They are now targeting tomorrow - with a backup option the day after.

 

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Hop attempt in ~33 minutes.
Or shortly before the next hour.

Livestream

Edit: A siren warns of the test 10 minutes before the hop, that happened 18:44 local time, so 18:54+ for the hop, could happen nearly any minute now.

Edit2: Looks like it will take a bit longer. Venting reduced, they might remove the fuel, fuel it again and try again.

 

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Scrubbed: "Scrubbed for the day. A Raptor turbopump spin start valve didn’t open, triggering an automatic abort. We’ll figure out why & retry tomorrow."

 

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Another attempt is on the way, the vehicle is being fueled and the engine is cooled down in preparation of a hop. In the chat people think they heard the siren, that would make the launch attempt 10 minutes away. That would be unusually fast, from the fueling I would expect an attempt in ~30-50 minutes.

Edit: Everydayastronaut reports hearing the siren (livestream)

Launch 18:54 local time?

 

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IT FLEW!

And it's still standing.

Such a surreal flying object.

Here is a video

 

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SpaceX released a video of the flight:



Those stubby landing legs are a very preliminary solution, they are working on longer legs, and eventually legs that can land on unprepared surfaces (such as the Moon and Mars).

Some more tweets:
Expect several shorter hops before high altitude flights
Hop and direct reflight "soon"

 

[f95toli]

A flying grain silo

Jokes aside, they are making impressive progress. Also, the way they work is so different from how conventional wisdom says that you should run large development project.

 

[jackwhirl]

Love it. Any word or pictures on whatever was blown off the test stand(?) @ ~12 seconds into the SpaceX video?

 

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Not sure what it was (here are some people speculating), but it might be related to the incomplete structure: SN5 has a single Raptor engine that is offset from the center (the final design will have 3 center engines in a triangle and three outer engines), which means it doesn't launch vertically, it goes sidewards in addition to upwards. That means the exhaust hits some things that are not meant to be hit by exhaust. The launch pad might be quite preliminary, too.

Maybe that's part of what Musk meant by "several short hops to smooth out launch process". They want to reduce the damage a launch does.

 

[gleem]

What about those flames around the engine as it is landing? Don't think those are supposed to be there. Another item to be smoothed out?

 

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Looks like the launch is the main concern for now. The engines are probably quite robust.

Launch pad views:
From the air
From the ground - some tank wall was damaged

Tweet from Musk, asked when SN5 will fly again:

Not sure yet, but hopefully. Will need leg & other repairs. Probably SN6 flies before SN5. We need to make flights simple & easy — many per day.

 

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SN6 has been moved to the launch pad and tested at cryogenic temperatures to an unknown pressure.
Picture

Most likely the next steps will be a static fire and then a hop while SN5 is inspected/repaired/upgraded.

 

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SN6 static fire

A hop is planned for Friday or the weekend.

 

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Siren was heard 13 minutes ago, hop could be imminent, but it's also possible that they aborted this attempt.

Edit: Aborted, next road closure is Thursday, September 3.

 

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Successful hop!
With one engine that's not in the center the hops always look a bit tilted, but that's by design. The longer flights will be done with more engines, then the thrust is more symmetric.

 

[gleem]

Elon being a little optimistic?

 

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They asked for a 20 km flight permission October 11, that's one month from now. It's fast, but nothing too unrealistic. Some fins were spotted on the way to the construction site. Attach all fins, add the nose, get the full Starship to the launch site. By that time the SN7.1 tank might have been tested to destruction so SN8 can start its test program - probably wet dress rehearsal, static fire, and then a flight. Later in October is more likely, even if everything goes right. At some point in October Musk plans to give an update on the status, they'll probably try to make the flight before that.

 

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SN7.1 is being tested right now - the target is a test to destruction. The tank is ~2/3 filled at the time of this post:

SN8 got aerodynamic surfaces, it's getting closer to being moved to the launch pad.Meanwhile people have spotted the first elements that are clearly part of the first Super Heavy prototype, three stacked rings:

 

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SN7.1 is being tested right now - the target is a test to destruction.

And... it got destroyed. 4:58:10 local time (see the bottom of the livestream)
Looks like the front fell off. The top end of the tank is gone.

 

[gleem]

Apparently, the starship SN8 passed its static fire test with three raptor engines early this morning.

 

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NASAspaceflight article
First time multiple Raptor engines fired in parallel.

If SpaceX is happy with the test result they'll attach the upper half of SN8 (the payload area of future Starships), do another static fire test, and then fly to 15 km.
There is no official public test plan but it's generally understood that this static fire was using the main tanks, whereas the next static fire will use the header tanks (used for landing). One of the header tanks is in the upper section that's not installed yet.

 

[jackwhirl]

Per Musk, the static fire data looks good:


I am curious where they will stack the fairing. I expected them to take it back to one of the mid/high bays, but this article speculates they will stack on the pad:
https://www.teslarati.com/spacex-starship-nosecone-installation-static-fire-success/
Since we are currently in the middle of their first road closure and the live cams show SN-8 is still on the pad, I presume that's correct.

 

[gleem]

A very large crane is currently moving toward SN8 presumably to place the nose cone on it.

 

[jackwhirl]

Looks like a good bet. Nosecone is headed there now, too.
Pic in spoiler.

Spoiler

 

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They lifted the nose cone on top of the tank section half an hour ago. Looks like they are welding it together at the moment.



From the stream:

 

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Michael Baylor on Twitter:

SpaceX is targeting Nov. 9 through Nov. 11 for Starship SN8's flight to 15 kilometers, per the lastest road closures. These windows may also include static fire testing.

 

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Static fire complete.
-18 minutes right now (timestamps in livestreams are awkward) or here on Twitter.
Something flew away, unclear if that was intended or not.

Flight date to be determined, potentially as early as tomorrow but next week is more likely.
This will either make a spectacular flight with a crazy landing maneuver or crash in a spectacular way, either way it will be worth watching.

Edit: People familiar with SpaceX say there will be two more static fires - one with two engines and one with three engines - before a flight attempt. That puts the flight at least two days into the future, and therefore after Crew-1.

 

[gleem]

Static firing last night did not end well but could have been worse. The test is discussed here.

 

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Musk explained on Twitter that the exhaust broke up the ground and a rock damaged the engine bay. The normal approach would be to simply strengthen the test stand - but remember that this spacecraft is expected to land and take off on Mars, too, where this type of damage is a concern. So they decided to reinforce the spacecraft as well.

A new engine has been moved to SN8, indicating that they don't need larger repairs beyond changing the engine.
They probably need to repair the ground and repeat the static fire test, no time estimates yet. The time isn't lost, SN9 is approaching completion and SuperHeavy makes progress. SN10-12 are in various stages of assembly.

 

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Road closure Nov 30 (with Dec 1 and 2 as backup dates) for the 15 km flight.

There is an earlier road closure Nov 23/24/25, presumably for a repetition of the static fire test, but the Nov 30 closure reason is explicitly given as a flight.

 

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There is an earlier road closure Nov 23/24/25, presumably for a repetition of the static fire test

Static fire complete. People saw smaller pieces of concrete flying around but there is no obviously visible damage this time.

23:22:55 UTC:
Edit: Good static fire confirmed.

Edit: Not earlier than Wednesday December 2. One more static fire before that.

 

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The FAA has issued a NOTAM ("notice to airmen") to avoid a zone around the planned flight area from December 4 to December 6. This is a key requirement for a flight and SpaceX only gets a NOTAM when they are reasonably confident they can fly.
https://tfr.faa.gov/save_pages/detail_0_8423.html
https://www.google.com/maps/d/u/0/viewer?mid=1kQOqXZlh8VUqT_07NNnBNkaDuJlBORA-&ll=25.99185682202349%2C-97.10829015&z=11

Edit: NOTAM retracted, not earlier than Monday

Edit2: Now NET Sunday? Altitude was reduced a bit to 12.5 km.

 

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It's getting serious.
SpaceX Livestream starts in 13 hours, Tuesday at 14:00 UTC, that's in the morning local time.

A launch might happen at any time during the day or the following two days, but there will be some ahead warning - first from fueling, then from a siren 10 minutes before launch. And of course SpaceX might talk about plans in the livestream.

Spectacular landing maneuver or spectacular crash - it's guaranteed to be interesting.

On a less serious note, here is a sped-up flap test, that looks like it would try to take off with them.

 

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Now targeting liftoff 4:30 CST

That's in 12 minutes!

Edit: Abort just at ignition. No flight today, maybe another try tomorrow.

 

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Starship is getting fueled again.
SpaceX livestream in 20 minutes

 

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Livestream is running.

Countdown is being held at T-2minutes.

Edit: A ship is in the restricted area, new planned time 16:40 CST, 22:40 UTC, in 1:15.

 

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We got everything! A takeoff, a flight to 12.5 km with three, two, then one engine, the skydiver maneuver to slow down, the flip maneuver, and then a big explosion as it hit the landing pad too hard.
It looks like one of the engines stopped working in the final landing burn?

They'll clean up and prepare SN9 for a repetition of that test. It should be fully assembled already.

Edit: Musk tweeted: Fuel header tank pressure was low during landing burn, causing touchdown velocity to be high & RUD, but we got all the data we needed! Congrats SpaceX team hell yeah!

 

[jackwhirl]

Awesome flight. I was a little worried when the engines started going out. I hadn't anticipated a staggered shutdown like that.

So will they try to fix the pressure loss in SN9 or move directly to a later test article?

 

[iVenky]

I have a basic question. The motivation behind belly flop is to use air as brakes with higher surface area? And this gives us better control over landing?
Pumped up for SN9!

 

[jackwhirl]

Yes, Musk discussed that in his 2019 presentation. (~16 minutes in) It's all about shedding velocity.

 

[iVenky]

Yes, Musk discussed that in his 2019 presentation. (~16 minutes in) It's all about shedding velocity.

Yes, I saw a video where SN8 was really slow with the belly flop maneuver. Can't believe with my own eyes. Seems like magic!

 

[jackwhirl]

They've got to be feeling good about their computational models right now. It was a beautiful dive, and looked just like the simulations.

 

[nsaspook]

The 'landing' reminds me of this:

 

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The header tank with the lower than expected pressure contains methane. With a lower pressure you can't pump enough fuel. Typically engines run "fuel-rich", i.e. with more fuel than needed for an optimal combustion. What happens if you have hot oxygen without enough methane? The oxygen reacts with the engine. In particular, it reacts with copper parts, which makes the exhaust green. Running without enough fuel is jokingly called "running engine-rich".

Here is a video looking up from the landing pad. It's pretty clear where the problems start. Quickly afterwards one engine stops completely.

This should be relatively easy to fix. They'll certainly look over all other flight phases as well, but it looks like SN9 can make another attempt soon. Maybe even this month.

Ars Technica: So, it turns out SpaceX is pretty good at rocketing

Looking beyond the 12.5 km flights: If they mount six engines then Starship can go to space (suborbital), testing faster re-entry with significant heating, with or without heat shield (it's still much easier than orbital re-entry).
They work on the first prototype for SuperHeavy, that will make its own test flights starting with two engines. Eventually we'll see both together, probably when they try to reach orbit. At that time the heat shield needs to work.

 

[bob012345]

I worry about the stability of the tall and narrow design as far as landing on the Moon and Mars. If you look at the video from SN8 it was not perfectly vertical at 'landing'. Perhaps that was just due to lack of thrust? I also worry about a lot of big windows on the projected designs. I prefer mainly steel and not glass when I'm that close to an infinite vacuum.

 

[jackwhirl]

Do we know if the header tanks were pressurized autogenously for this test, or is that something they are still looking to add in the future?