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Sorry to divert from Starship-

But I see Wikipedia has the inflight abort test flight of D2 penned in for September. Did I miss i it or has SpaceX just completely forgot about it?

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45 minutes ago, ZooNamedGames said:

Sorry to divert from Starship-

But I see Wikipedia has the inflight abort test flight of D2 penned in for September. Did I miss i it or has SpaceX just completely forgot about it?

Wiki not the most up to date. After the DM-1 capsule blew up because of that valve in a Draco/Super Draco test, MaxQ abort got pushed back since they are using the second capsule for it, instead of reusing the one they flew to ISS. Supposedly coming up at some point in the next few months.

 

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Just now, tater said:

Wiki not the most up to date. After the DM-1 capsule blew up because of that valve in a Draco/Super Draco test, MaxQ abort got pushed back since they are using the second capsule for it, instead of reusing the one they flew to ISS. Supposedly coming up at some point in the next few months.

Last I heard it was NET mid November, I think, with Demo-2 NET Dec. 17, but darned if I can find it now.

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6 hours ago, CatastrophicFailure said:

Last I heard it was NET mid November, I think, with Demo-2 NET Dec. 17, but darned if I can find it now.

That sounds likely.

SpaceX has bunch of possible launches in the next few months (mostly Starlinks).

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Can someone tell me what the purpose of the second stage of parachutes (the one with two chutes) is?  I get that you'd want the first to increase drag and ensure the capsule is in the right orientation before deploying the next chutes, but what's the purpose of the two chutes (that don't even open fully before being jettisoned)?

Concerning Boca Chica village, and the resident's comments, I'm afraid I'm having trouble buying it.

"the offers did not account for the unique wilderness and view of Boca Chica" - If they were that valuable, it'd be reflected in the prices of the homes.
"a handful of families do not have the financial means, even with a three-times-appraised-value offer, to buy equivalent properties elsewhere."  I call total BS on this.  
The 40-ish houses close to the launch pad are valued between $70k and $100k, for 1000-1400 square feet.  If SpaceX paid out $210-300k to each resident, that's plenty of money to buy a house elsewhere.  Heck, just down the road in Brownsville, there are boatloads of houses larger than 1,200 square feet and under $200k in price.  The same goes for Port Isabel and Laguna Vista just to the north.

I totally understand the sense of community, of personal investment into a property, the ownership, the fear of moving, the resistance to being asked to move, etc.  I get that SpaceX said one thing a while back, and are now asking for something else.  Those are all legitimate concerns.  But to claim that the $150-200k windfall SpaceX is offering you is insufficient to allow you to settle elsewhere is baloney.

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6 minutes ago, zolotiyeruki said:

Can someone tell me what the purpose of the second stage of parachutes (the one with two chutes) is?  I get that you'd want the first to increase drag and ensure the capsule is in the right orientation before deploying the next chutes, but what's the purpose of the two chutes (that don't even open fully before being jettisoned)?

The first 2 are the drogues, they pull out the main chutes.

The first, solitary chute was to flip the capsule into a tumble since this was to test a launch abort condition.

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Just now, tater said:

The first 2 are the drogues, they pull out the main chutes.

The first, solitary chute was to flip the capsule into a tumble since this was to test a launch abort condition.

It doesn't look to me like the first parachute (after release, not the tiny white one at the very beginning) is making the capsule tumble.  On the contrary, it looks like it's stabilizing the capsule.  Is the first, solitary chute normal equipment, or was it used specifically for this test?

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Just now, zolotiyeruki said:

It doesn't look to me like the first parachute (after release, not the tiny white one at the very beginning) is making the capsule tumble.  On the contrary, it looks like it's stabilizing the capsule.  Is the first, solitary chute normal equipment, or was it used specifically for this test?

When it released, an extra line that was attached around the capsule cased it to tumble nicely.

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1 minute ago, Brotoro said:

When it released, an extra line that was attached around the capsule cased it to tumble nicely.

Ah, you're right--it's when that parachute is released that it causes the tumble.  Thanks!

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Why 3 mains instead of 1? Why 2 drogues instead of 1?
Probably just for redundancy, like others do.

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8 minutes ago, kerbiloid said:

Why 3 mains instead of 1? Why 2 drogues instead of 1?
Probably just for redundancy, like others do.

Apollo 15 had 1 of its 3 main 'chutes fail to deploy.  But the Command Module was designed to be able to safely land in the water with just 2.

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18 minutes ago, Jacke said:

Apollo 15 had 1 of its 3 main 'chutes fail to deploy.  But the Command Module was designed to be able to safely land in the water with just 2.

As well, VA of TKS on video had landed on 2 when the 3rd one failed.
3 instead of 1 make unnecessary a backup chute and a delay between you realize that the single main has failed and the backup should be engaged.

Edited by kerbiloid

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All three Apollo 15 main chutes deployed properly. But one of the chutes was apparently damaged during the RCS fuel dump, and that chute collapsed.

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I was wondering...when Starship lands on Mars, won't it sink into the sand, or tip over? The feet that it has to land on look to be less than 1 metre in diameter, for a craft 55 metres tall with a dry mass of 85 metric tons. That's a lot of pressure on each pad, and could really cause stability issues if the spacecraft lands on a soft surface like sand. I wonder if they've considered this, and if so, how they're going to handle it?

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@RealKerbal3x I think the fact that they'll be in about 1/3rd of Earth's surface gravity should help quite a bit.

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If it's deep sand, I'd be more worried about what the rocket exhaust would do to the surface than whether the legs will sunk in

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Maybe they'll have something like Falcon 9's landing gear, with three legs alternating with the fins? That fin doesn't look like it has any form of leg inside. 

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2 minutes ago, RealKerbal3x said:

@ThatGuyWithALongUsername Iiiinteresting. Looks like the fin design has changed somewhat...I wonder if the fins still double as landing gear.

Well... IIRC Elon *did* say it had changed again. And it doesn't really look like there's landing gear on them, combined with Elon saying certain structures were "landing leg mounts" on Twitter makes me think that yeah, they're separate again.

 

IMO it looks kinda like a blend between the 2017 BFR and the 2018/19 Starship. I wonder if there are still three fins, or if they've gone back to 2 (after all, didn't Elon say the third one was really just a landing leg?) Did they right-click the symmetry button?

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6 minutes ago, ThatGuyWithALongUsername said:

Well... IIRC Elon *did* say it had changed again. And it doesn't really look like there's landing gear on them, combined with Elon saying certain structures were "landing leg mounts" on Twitter makes me think that yeah, they're separate again.

It'll be interesting to see what the landing legs look like now. The finlegs do give quite a wide base, which increases the angle required for the ship to tip over, as I demonstrate with this diagram:

Dw4nyU6.jpg

(Note that I approximated the COM location and total fin diameter).

If the legs are now simply struts sticking out from the main body, that'll make the ship more liable to tipping.

Edited by RealKerbal3x

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Just now, RealKerbal3x said:

It'll be interesting to see what the landing legs look like now. The finlegs do give quite a wide base, which increases the angle required for the ship to tip over, as I demonstrate with this diagram:

Dw4nyU6.jpg

If the legs are now simply struts sticking out from the main body, that'll make the ship more liable to tipping.

Good point. *like*

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3 minutes ago, RealKerbal3x said:

It'll be interesting to see what the landing legs look like now. The finlegs do give quite a wide base, which increases the angle required for the ship to tip over, as I demonstrate with this diagram:

Dw4nyU6.jpg

(Note that I approximated the COM location and total fin diameter).

If the legs are now simply struts sticking out from the main body, that'll make the ship more liable to tipping.

Or they can have a leg mounted, offset to the fins.

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