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5 hours ago, RCgothic said:

From what I've heard on Reddit, it was a ridiculously close call and insiders say they're not going to release it for PR reasons.

Firstly, look at the scorch trail across the barge. Also the last frame shows spray being kicked up way off the mark. The rocket clearly pulled some crazy last minute manoeuvres.

Secondly, insiders describe the booster balancing on one leg and nearly toppling. There is also a reference to CRS6 and the little thruster that couldn't. Apparently this time it could.

So the video sounds ridiculously awesome, but don't hold out any hope for a release!

It still seems odd, considering that they released the footage of failed landings. Plus, it reflects well on SpaceX that their rocket can land even in terrible situations.

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28 minutes ago, CatastrophicFailure said:

I thought the "old dragon" was going to live on for a while as the cargo ship? D2 was only for crew?

Previously-flown Dragon 1 spacecraft will continue to be used for CRS cargo missions as Dragon 2 development and testing continues. Once Dragon 2 comes online, new Dragon 2s will be used for both commercial crew and cargo missions alongside reused Dragon 1s until Dragon 1 end of life.

Elon hinted at using cargo missions to test Dragon 2 more aggressively than would be possible with crew. We may yet see propulsive landing, if only to splashdown.

If I have some time tomorrow, I'll work up the numbers on a real nine-meter ITS.

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2 hours ago, sevenperforce said:

Previously-flown Dragon 1 spacecraft will continue to be used for CRS cargo missions as Dragon 2 development and testing continues. Once Dragon 2 comes online, new Dragon 2s will be used for both commercial crew and cargo missions alongside reused Dragon 1s until Dragon 1 end of life.

Elon hinted at using cargo missions to test Dragon 2 more aggressively than would be possible with crew. We may yet see propulsive landing, if only to splashdown.

If I have some time tomorrow, I'll work up the numbers on a real nine-meter ITS.

Can dragon 2 be used for cargo? as in could you use berther instead of docking? 

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Yeah, this was stated a while ago, that D2 would be crew missions, and would then replace D1 for cargos well.

That's why many were sad about propulsive landings, as they could have tested on cargo returns (and it would be cool as heck to see---maybe another use for "bouncy house"---as long as it's made of asbestos :wink: ).

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6 minutes ago, tater said:

Yeah, this was stated a while ago, that D2 would be crew missions, and would then replace D1 for cargos well.

That's why many were sad about propulsive landings, as they could have tested on cargo returns (and it would be cool as heck to see---maybe another use for "bouncy house"---as long as it's made of asbestos :wink: ).

I'm still holding out for propulsive splashdowns on cargo returns. No reason they can't at least test it out.

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2 hours ago, captainb said:

Musk stated that they found a "better way" to do Mars landings.  Any ideas what that might be?

Spoiler

They understood that the space is indeed an endless solid rock with "planet" hollows...

35d806b2a32c529f9084b5a953235ed3--hollow

...and bet on HITS - Hyperloop Interplanetary Tunnel System.

tunnel_20boring_20machine-275x125.jpg

Spoiler

Their secret slogan will be: "Space flight is boring!"

 

Edited by kerbiloid
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3 hours ago, captainb said:

Musk stated that they found a "better way" to do Mars landings.  Any ideas what that might be?

Just a straight engine-first retropropulsion descent? They have a lot of practice with that by now. No heatshield required, so engines can be center-mounted instead of side-mounted.

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11 minutes ago, Streetwind said:

No heatshield required, so engines can be center-mounted instead of side-mounted.

Or they have visited a bookstore.
https://www.wired.com/2012/10/origin-of-the-apollo-shaped-manned-mars-lander-1966/

Pay attention to its hull shape and fins.

Spoiler

aeronutronic6.jpg

 

Edited by kerbiloid
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6 hours ago, magnemoe said:

Can dragon 2 be used for cargo? as in could you use berther instead of docking? 

Dragon 2 doesn't have a CBM, so it can't be berthed.

But nothing prevents you from delivering cargo through a docking port. Only ISPR racks require a CBM and there are no plans to carry any up or down at this stage.

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The inescapable problem with landing with downward-facing engines, assuming you intend to use those engines again, is regolith damage. Rocks and debris kicked up by the engine plume are almost guaranteed to damage your engine bells, and then you're boned. 

The LM (and, if I read the diagrams correctly, the Mars Lander shown above) had its ascent engines shielded during descent, so this wasn't a problem. Red Dragon would have had its SuperDracos tucked up above the heat shield, albeit with some cosine losses. But ITS and anything with a similar profile is going to have to land on its engines, and that seems really problematic. Having long landing legs helps, I suppose, but it still seems like unacceptable risk.

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28 minutes ago, sevenperforce said:

The inescapable problem with landing with downward-facing engines, assuming you intend to use those engines again, is regolith damage. Rocks and debris kicked up by the engine plume are almost guaranteed to damage your engine bells, and then you're boned. 

The LM (and, if I read the diagrams correctly, the Mars Lander shown above) had its ascent engines shielded during descent, so this wasn't a problem. Red Dragon would have had its SuperDracos tucked up above the heat shield, albeit with some cosine losses. But ITS and anything with a similar profile is going to have to land on its engines, and that seems really problematic. Having long landing legs helps, I suppose, but it still seems like unacceptable risk.

Well, this is only a problem for the first ITS, building a clean, flat surface for the next ones seems extremly easy compared to the other challenges.

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 Cosine losses are not undesirable in 2 regimes. For entry, they increase the effective area contributing to drag via the larger bow shock, and for landing when a craft cannot throttle deeply enough to hover.

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