Building the Full Metal Starship testbed: Starhopper

[Grendal]

Video from the Everyday Astronaut captures Starhopper debris tumbling out of the dust cloud obscuration on the right of the screen. It occurs just after the 1:42:20 mark. Suppose it could be a COPV and possibly also the panel it was mounted on. The launch sequence begins at 1:41:15. Agree with HVM, likely no big deal. Raptors rule!

It looked like one of the attached cold gas thruster pods that where reused from old Falcons. Or a COPV tank. Here is the official SpaceX video:

 

[MyJoule]

It sure looks like something that is a cross between a Rocket engine and a water tower

I'm amazed at the fine control they demonstrated today. Way to go SpaceX's Starhopper team

 

[ICUDoc]

Awesome!
Mach diamonds, cold gas thrusters, Raptor vectoring and fine control all made me happy. The best thing I've seen today.
Why does the Raptor exhaust change colour all the way back up to the rocket when the tail-end of the exhaust first touches the ground just before landing? It goes bright orange instead of blue-and-yellow. And the Mach diamonds disappear...
Forgot to add: and it looks like me and my sons knocked it up in our backyard. Looks almost deliberately ramshackle.
And reminds me of an early Lost in Space episode!

 

[HVM]

All four COPVs are still there. So what was it?

Jack Beyer on Twitter

Here is the unknown flying pressure vessel (UFPV)
Trevor Mahlmann on Twitter

 

[diplomat33]

All four COPVs are still there. So what was it?
View attachment 447303
Jack Beyer on Twitter

Here is the unknown flying pressure vessel (UFPV)
Trevor Mahlmann on Twitter

That is a beautiful picture of the hopper.

 

[HVM]

Awesome!
...Why does the Raptor exhaust change colour all the way back up to the rocket when the tail-end of the exhaust first touches the ground just before landing? It goes bright orange instead of blue-and-yellow.

Some say that it's due throttling and uneven combustion. But it's visible with other vehicles and during lift off too, so the orange color is probable end result of flame reacting with dust cloud.

 

[mongo]

Awesome!
Mach diamonds, cold gas thrusters, Raptor vectoring and fine control all made me happy. The best thing I've seen today.
Why does the Raptor exhaust change colour all the way back up to the rocket when the tail-end of the exhaust first touches the ground just before landing? It goes bright orange instead of blue-and-yellow. And the Mach diamonds disappear...
Forgot to add: and it looks like me and my sons knocked it up in our backyard. Looks almost deliberately ramshackle.
And reminds me of an early Lost in Space episode!

My guess is that the reflected pressure wave disturbs the exhaust flow. Turbulence prevents the Mach diamond formation and orange is CH4 that cooled from hitting the ground and then combusted in a less oxygen rich environment.

You can see a potentially similar phenomenon if you get a nice small laminar flow from a faucet and then put your finger in the stream and move it toward the spout.

 

[Nikxice]

Last night on Twitter Scott Manley (With an MS in physics, just one his many exceptional credits) attributed the Raptor exhaust plume color change to "black body radiation from the dust". Google can help to understand, others here might be able to simplify the concept. Scott will likely go into more detail during his next YouTube video.

 

[dhanson865]

View attachment 447126

To quote someone on reddit that paraphrased Douglas Adams:

"The hopper hung in the sky in much the same way that bricks don't."

 

[Cosmacelf]

Awesome stuff. So, what’s next?

 

[diplomat33]

Awesome stuff. So, what’s next?

I think SpaceX is already working on building a fully assembled, full size, starship.

 

[mongo]

Awesome stuff. So, what’s next?

In some order:

• Starships Mk 1 and Mk 2 with 3 engines doing sub orbital tests
  
• Super Heavy tests
• Starship (6 engine) + SH orbital tests
  
• Uncrewed Moon flyby trip
• Dear Moon trip
  
• Crewed? moon landing
• Crewed moon landing
  
• Uncrewed Mars
• Crewed Mars
• Europa
• Infinity
  
• Beyond

 

[HVM]

Awesome stuff. So, what’s next?

Starship Orbital Prototype - Texas Version

 

[mongo]

Awesome stuff. So, what’s next?

Twitter

 

[e-FTW]

Man those water tower company workers have got to be going a little nuts!

Water Tower to Mars™!

 

[dhanson865]

Man those water tower company workers have got to be going a little nuts!

Water Tower to Mars™!

I'd have to say they have all changed their resumes (or created one if they didn't have one previously). Saying you built the first flying prototype of a Full-flow staged combustion powered spaceship is a pretty big line item on a resume. Especially considering it's never happened before in the entire know history of the world as we know it.

As of 2019, only three full-flow staged combustion rocket engines had ever progressed sufficiently to be tested on test stands; the Soviet Energomash RD-270 project in the 1960s, the US government-funded Aerojet Rocketdyne Integrated powerhead demonstration project in the mid-2000s,[5] and SpaceX's flight capable Raptor engine first test-fired in February 2019

I'd have to imagine they got a bonus for a milestone achievement. Probably have another bonus coming up for the starship when it first flies.

 

[diplomat33]

Elon is already hinting at an even bigger Super Heavy Starship with a diameter of 18 meters. That would be twice the width of the current super heavy starship!!!
SpaceX CEO Elon Musk says Starship could be followed by a dramatically larger rocket

 

[e-FTW]

Sad to hear (from Scott Manley) that this beautiful water tower will probably become some type of test stand. But hey, we won’t care much once the Orbital Water Prototypes start flying!