SpaceX Starship (/Super Heavy) testing: Untethered hops TBD

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Previously discussed in the "Space Stuff" thread but this is a long-term project.

What is Starship?
SpaceX is working on a fully reusable two-stage rocket to replace the partially reusable Falcon 9/Falcon Heavy. It is the largest rocket that made it beyond the concept phase so far; the payload will be 100-150 tonnes to low Earth orbit. Both stages are expected to be fully and rapidly reusable, a bit like aircraft, as this can reduce launch cost massively. The lower stage is called Super Heavy, the upper stage is called Starship, the combination doesn't have an official name. Starship is the revolutionary part of it. It will come in several versions - a satellite deployment version, a tanker version (to refuel other Starships in orbit) and at least one passenger version. The ability to refuel in orbit gives it an unprecedented capability for flights leaving Earth. The same 100-150 tonnes can be launched to low Earth orbit can also be launched to the Moon or Mars.
The early business plan is the satellite deployment - cheaper than Falcon 9 and with a larger payload than Falcon Heavy it can take over all its flights. As long-term goal it is planned to fly humans to Mars, and maybe even beyond. It could also enable super-fast Earth to Earth transportation - flights would be under an hour where airplanes need up to ~20.

Current status
In early 2019 SpaceX built a subscale prototype called Starhopper. It has the same diameter but not the same height. It made first hops in April - held down with tethers, its maximum height was about 1 m.
In parallel SpaceX is constructing two full-scale Starship prototypes with by two teams who compete/cooperate.
Construction of Super Heavy is expected to start in about 3 months (August). By that time the Starship vehicles should have their outer structure finished.

Test plan
SpaceX is currently preparing for untethered hops of Starhopper. The first of them is expected to be about 20 m, roughly its own height, and could happen next week. It will be done with just one Raptor engine installed. Later hops will use three engines and be up to 5 km high, this is the limit of the permission SpaceX got for hops there. This is a bit similar to the Grasshopper tests that lead to the reusable boosters of Falcon 9.
The full-scale prototypes are expected to make high-altitude/high-velocity flights later this year. Super Heavy will follow later and combined orbital flights were announced for 2020.


If this works remotely as expected it will revolutionize spaceflight, crewed and uncrewed. Just plugging in numbers from SpaceX you might be able to buy a short trip to space for $5000. They can get a very long queue of customers. The big unknown is the safety: Can the system go from the ~2-5% failure rate of current rockets to a value close to the ~0.0002% of modern aircraft?


Science Advisor
Apparently the test has been put off again until June 17 through June 19. One source of this information is the Cameron County TX notice of road closure around the SpaceX test facitlity.
Apparently they had some engine damage. Both a presentation planned for June 20 and the first flight might shift to July.

Edit: NET July confirmed

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While flight tests of the hopper get delayed due to engine issues (see the edit in the previous post) work on the orbital prototypes makes progress.

This is the status on the East Coast (from here):


View from a different angle

This looks close to the renderings already.
The full Starship height is about 4 times the height of the nose section (plus feet). The larger piece might be twice the height of the nose, the section next to it is a bit below that, so we are at ~2.5 out of 4 or so, a bit more than half of the outer structure is done.
The hexagonal object to the left of the cylindrical section could be the start of the engine section.

Edit: Boca Chica (Texas) site seems to be near completion of the hull. Here is an overview, the three green rings are still missing.
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Science Advisor
No road closures notices around South Padre Island or FAA Notices to Airmen posted(NOTSAM)for the near future. Starhopper test awaiting raptor engine test first per
The test schedule changed a bit - only a static fire (using the engine while standing on the ground) on Tuesday, hop on Wednesday. Based on the video of the static fire the hop might be delayed - significantly.

The video starts playing seconds before the static fire test that seemed to work normally. But watch what happens 51:15...

No official news yet.

Edit: Spacecraft looks fine, no visible damage at least. Probably rapid combustion of fuel that was vented after the test.

Edit2: No flight tests this week, new schedule to be determined.
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