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Hoppy went for a nice Sunday drive today. Video by Mary once again. The black thing sticking up from the ground to the left is where Hoppy's umbilical connects and where it suckles, the place where it started out from on Thursday. Hoppy wasn't driving a Tesla. (Don't tell Elon!) It was atop two heavy duty roll-lift crawlers.

https://twitter.com/NASASpaceflight/stat...6152486912

(Jul 28, 2019 08:34 PM)Yazata Wrote: [ -> ]Hoppy went for a nice Sunday drive today. Video by Mary once again. The black thing sticking up from the ground to the left is where Hoppy's umbilical connects and where it suckles, the place where it started out from on Thursday. Hoppy wasn't driving a Tesla. (Don't tell Elon!) It was atop two heavy duty roll-lift crawlers.

https://twitter.com/NASASpaceflight/stat...6152486912

(Jul 26, 2019 05:03 PM)Yazata Wrote: [ -> ][earlier] . . . They are launching this thing by directing the rocket exhaust at a concrete slab instead of into a Cape Canaveral-style flame-duct. So the blast is reflected back up. That's why it's so fiery and it obscures the visuals.

No crawlers to move the complete deal on Mars (at least for a long time), should troubles land it too far from a research, fuel, and repairs base.

Won't have either a concrete slab or a flame duct when launching from Mars, either. At least there won't be any grass fires there.

Just after it lands and the engines shut off, hopefully no weirdly behaving Martian dirt and rocky debris as it cools will pop up into the engines and cause trouble later during a lift-off. Explorers/colonists will surely make an examination for that sort of thing, anyway.

Would be interesting to see how much of the guidance/attitude control was due to thrust vectoring and how much was due to attitude jets (if any.)

(Jul 29, 2019 04:41 AM)C C Wrote: [ -> ]No crawlers to move the complete deal on Mars (at least for a long time), should troubles land it too far from a research, fuel, and repairs base.

The engineers are talking about that. Speculation is that Starships will land some safe distance from Lunar/Mars ground support equipment to minimize the danger of coming down atop them if things are a bit off. So the ground support equipment will have to have some mobility. Crawlers, flexible hoses or whatever.

Quote:Won't have either a concrete slab or a flame duct when launching from Mars, either. At least there won't be any grass fires there.

Right. Speculation is that's why they are doing things this way here on Earth. They want to design a vehicle able to launch from unprepared surfaces and relatively resistant to 'FOD' (foreign object debris).

Quote:Just after it lands and the engines shut off, hopefully no weirdly behaving Martian dirt and rocky debris as it cools will pop up into the engines and cause trouble later during a lift-off. Explorers/colonists will surely make an examination for that sort of thing, anyway.

Just from photos of Mars' surface, there's lots of rocks and stuff that could easily be kicked up. Damaging the engines is a vulnerability.

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(Jul 29, 2019 04:36 PM)billvon Wrote: [ -> ]Would be interesting to see how much of the guidance/attitude control was due to thrust vectoring and how much was due to attitude jets (if any.)

I believe that it was almost all thrust vector control this time. There are control thrusters taken from Falcon 9's, reportedly a set salvaged from the booster that went into a spin and crashed into the sea and also another set of older-model thrusters no longer used on block 5 Falcons that they probably had on the shelf, doubled up because of the Hopper's greater mass. As I understand it, the thrusters are only there to give the vehicle roll authority, the engine gimbaling handles pitch and yaw.

(Jul 29, 2019 05:51 PM)Yazata Wrote: [ -> ]I believe that it was almost all thrust vector control this time. There are control thrusters taken from Falcon 9's, reportedly a set salvaged from the booster that went into a spin and crashed into the sea and also another set of older-model thrusters no longer used on block 5 Falcons that they probably had on the shelf, doubled up because of the Hopper's greater mass. As I understand it, the thrusters are only there to give the vehicle roll authority, the engine gimbaling handles pitch and yaw.

I guess once they have more than one engine firing they won't even need roll thrusters.

(Jul 29, 2019 06:49 PM)billvon Wrote: [ -> ]

(Jul 29, 2019 05:51 PM)Yazata Wrote: [ -> ]I believe that it was almost all thrust vector control this time. There are control thrusters taken from Falcon 9's, reportedly a set salvaged from the booster that went into a spin and crashed into the sea and also another set of older-model thrusters no longer used on block 5 Falcons that they probably had on the shelf, doubled up because of the Hopper's greater mass. As I understand it, the thrusters are only there to give the vehicle roll authority, the engine gimbaling handles pitch and yaw.

I guess once they have more than one engine firing they won't even need roll thrusters.

The Starship prototypes will reportedly have three raptor engines. So yeah, the talk is that they will be able to control roll as well as pitch/yaw by gimbaling.

In today's Boca Chica news, they have lowered the previously-mentioned fuel-tank bulkhead into the cylinder, the lower half of the emerging 'Mark 1' Starship prototype.

https://twitter.com/BocaChicaGal/status/...3809757184

And what appears to the engineers to be the thrust structure, to which this vehicle's three Raptor engines will be fitted, has made its appearance. It will presumably be assembled near the bottom of the cylinder.

https://twitter.com/NASASpaceflight/stat...9118218240

So the thing is starting to become more than a steel shell and is acquiring the beginnings of some guts.

Looks like we might have tentative dates for Boca Chica Hoppy's upcoming 200 meter flight.

Road closures have been announced for Monday August 12 (primary day), Tuesday August 13 (alternate day) and Wednesday August 14 (alternate day).

http://www.co.cameron.tx.us/wp/space-x/

200 meters is going to be spectacular, about 10x Hoppy's height and well above all the blast reflecting off the ground obscuring things. Hoppy should just be hovering there on a pillar of flame. Unsure where it will land, perhaps on the new landing pad with the stylized SpaceX 'X' newly painted on it. But... observers have noted that road grading might be necessary if they hope to move Hoppy between pads with those blue Roll-Lift crawlers. (The crawlers don't look very agile, especially when they are bearing such a big load.)

LOTS of new information on SpaceX's Starship/Superheavy plans in the just-filed environmental impact report. Everything from where the vehicles will be manufactured, how they will be transported and assembled, to necessary launch pad modifications. From rocket engine technical stats, to planned testing, anticipated launch frequency, reentry profile and associated sonic booms, exhaust plumes, to landing sites, to anything else that you can think of.

https://netspublic.grc.nasa.gov/main/201...arship.pdf

It seems to me that the biggest problem might be the Starships' reentry and landing. They will reenter at mach 25 over the Gulf of Mexico and land propulsively at Cape Canaveral. Sonic booms would be heard across all of central Florida and might be pretty intense as far away as Orlando. Besides, there is some crash-risk associated with very large spacecraft coming in over populated areas. (The Space Shuttle landed at Cape Canaveral, so there's precedent.)

So there's some speculation that if the government denies SpaceX authorization to do this, the landing pad might be moved to the west coast of Florida where all of the approach would be over open water. Launches from Cape Canaveral would go east and the plan is to land the giant Superheavy boosters on an oceangoing barge/'drone-ship' out at sea rather than back at the Cape. (Would have to be an awfully big barge.)

Proposed pad modifications in yellow:



Reentry and landing profile:



Sonic booms for Starship landing

A new road closure has just been announced for next Friday, August 9 in addition to the previously announced Monday August 12, Tuesday August 13 and Wednesday August 14.

Unsure if this means a flight test on that date, or just some kind of fueling/pressurization test that might present some explosion hazard.

http://www.co.cameron.tx.us/wp/space-x/