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19 hours ago, magnemoe said:

With legs poking trough the heatshields you need doors like the space shuttle landing wheels had. Doors who can open and who latches close so more systems although not an very critical one outside the latching as the leg would just push it open if it did not open beforehand.

It isn't that simple, at least if you want to land somewhere beyond earth: Your legs need to extend in order to land and after take off the doors need to close well enough for reentry back at earth.

If you want to extend the legs outwards, then you should bulge the hull around the extension path to give room.

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13 hours ago, CBase said:

It isn't that simple, at least if you want to land somewhere beyond earth: Your legs need to extend in order to land and after take off the doors need to close well enough for reentry back at earth.

If you want to extend the legs outwards, then you should bulge the hull around the extension path to give room.

I would wait to focus on Mars return with current version, will the marsship stand fully loaded on its legs on Mars at all? Mars gravity is 1/3 but that is 1/3 of fully loaded weight. 
I say its more likely they jack it up and redraw the legs. 

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45 minutes ago, RCgothic said:

Cargo Dragon 2 looks weird without Superdracos! Still has the porthole that isn't a porthole though, lol.

 

I'm trying to wrap my head around the decision to remove them. If it's for more payload, do they use the capability? If not, why not leave them in, just in case? Or, maybe removing them shows confidence in success? 

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1 hour ago, Lukaszenko said:

I'm trying to wrap my head around the decision to remove them. If it's for more payload, do they use the capability? If not, why not leave them in, just in case? Or, maybe removing them shows confidence in success? 

If the payload is mass-limited and not volume-limited, then they could use the same cabin and get more to orbit without the Superdracos.

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6 hours ago, RCgothic said:

Cargo Dragon 2 looks weird without Superdracos! Still has the porthole that isn't a porthole though, lol.

 

 

 

What docking / berthing adapter is it equipped with ? The main thrusters are still on the front, right ?

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10 hours ago, Lukaszenko said:

I'm trying to wrap my head around the decision to remove them. If it's for more payload, do they use the capability? If not, why not leave them in, just in case? Or, maybe removing them shows confidence in success? 

No point in reducing payload mass for a launch escape system on an uncrewed cargo capsule. The SuperDracos aren't used in the course of a normal mission anyway.

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3 hours ago, MinimumSky5 said:

Also, you can save on cost be eliminating them. The small unused space in the pods is hardly worth worrying about.

Another factor is splashdown, not having the 9 engines trough the hull make it easier to waterproof the capsule. 

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All legitimate answers which I considered myself, but for every answer I have even more questions...

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If the payload is mass-limited and not volume-limited, then they could use the same cabin and get more to orbit without the Superdracos.

If. But, is it?

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Also, you can save on cost be eliminating them. The small unused space in the pods is hardly worth worrying about.

True. But, it's supposed to be fully reusable.

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Another factor is splashdown, not having the 9 engines trough the hull make it easier to waterproof the capsule.

True, but again it's supposed to be reusable. So, is it really that big an issue?

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No point in reducing payload mass for a launch escape system on an uncrewed cargo capsule. The SuperDracos aren't used in the course of a normal mission anyway.

SpaceX's own history shows that it would be nice to have a way to salvage the payload in case something goes wrong. The question is, at what cost? Here it seems like they're actually going out of their way to remove a perfectly good system of salvaging it. Lost payload mass is indeed a serious cost; do they actually utilize it?

Again, all are legitimate but speculative answers; we don't don't what the real explanation is

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Something I was wondering about cargo dragon 2 is whether or not it will only have 2 fins. I have a 3d model of dragon  2 cargo and it only has 2 fins, I know why they would chose to remove 2 fins because solar panels are only mounted to 2 of the fins and the fins are pretty much only useful in an abort and because of the removal of the Super Dracos makes it impossible to abort but I don't know if this will be on CRS-21 or if it was just an earlier proposal that was integrated into this model. Here's the link if your interested: https://www.thingiverse.com/thing:4659177/files

 

Edited by Delta dart
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2 minutes ago, Delta dart said:

Something I was wondering about cargo dragon 2 is whether or not it will only have 2 fins. I have a 3d model of dragon  2 cargo and it only has 2 fins, I know why they would chose to remove 2 fins because solar panels are only mounted to 2 of the fins and the fins are pretty much only useful in an abort and because of the removal of the Super Dracos makes it impossible to abort but I don't know if this will be on CRS-21 or if it was just an earlier proposal that was integrated into this model. Here's the link if your interested: https://www.thingiverse.com/thing:4659177/files

Edit: I didn't know it already launched

It does only have two fins:

16 hours ago, RCgothic said:

 

And also, it hasn't launched yet, don't worry.

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2 hours ago, Lukaszenko said:

All legitimate answers which I considered myself, but for every answer I have even more questions...

Again, all are legitimate but speculative answers; we don't don't what the real explanation is

the mass difference makes the 1st stage do less work and allow for a RTLS  that is way less expensive for spacex.

Not pushing the booster means more profit for spacex

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Just now, Flavio hc16 said:

the mass difference makes the 1st stage do less work and allow for a RTLS  that is way less expensive for spacex.

Not pushing the booster means more profit for spacex

This mission isn't doing an RTLS, the first stage is landing on OCISLY.

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2 minutes ago, RealKerbal3x said:

This mission isn't doing an RTLS, the first stage is landing on OCISLY.

i stand corrected  and actually this strengthen my position: for this launch the booster will land 622kms downrange. For a starlink launch, where we know that spacex is pushing the falcon 9 to or very near his limit  the landing take place 628-633 kms downrange, so the new dragon pushes the falcon 9 way harder than the dragon v1 and removing the superdrako allow for more payload/ reuse of the booster

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