Author Topic: SpaceX's Autonomous Spaceport Drone Ship Discussion Thread 2  (Read 2413903 times)

Offline Kabloona

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Re: SpaceX's Autonomous Spaceport Drone Ship Discussion Thread 2
« Reply #580 on: 01/06/2015 02:38 AM »
Stephen Clark's article over at SFN confirms that

Quote
If the first stage lands intact, sources said the rocket will lock on to the Marmac 300 barge and technicians will vent propellants and toxic substances carried inside the booster before it starts a two-day journey back to port.   

« Last Edit: 01/06/2015 02:40 AM by Kabloona »

Offline QuantumG

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Re: SpaceX's Autonomous Spaceport Drone Ship Discussion Thread 2
« Reply #581 on: 01/06/2015 02:43 AM »
To be clear: they'll vent the LOX and store the toxic propellant in tanks. They won't be dumping fuel into the ocean. The RP-1 will stay in the rocket. (Great, and now I can't find my source for that.. I could swear Elon said it on the AMA, but a search of his replies doesn't include "RP-1" now.)

Edit: Gee, I sure hope it wasn't L2.


Source: CRS5 prelaunch press conference.
« Last Edit: 01/06/2015 04:18 AM by QuantumG »
I hear those things are awfully loud. It glides as softly as a cloud. What's it called? Monowhale!

Offline Robotbeat

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Re: SpaceX's Autonomous Spaceport Drone Ship Discussion Thread 2
« Reply #582 on: 01/06/2015 02:45 AM »
darkmo: So basically you're saying Musk may be lying. I doubt it. The propwash looks like it's coming right from where the thrusters are. Additionally, there's no sign of propwash from the (imaginary, in this case) towboat. Barges are often pushed, not towed, and if they ARE towed, the chains usually are plenty short enough that you'd see the tug in the frame. And even if the tug was slightly out of the frame, the propwash would be clear in the right portion this picture.
« Last Edit: 01/06/2015 02:49 AM by Robotbeat »
Chris  Whoever loves correction loves knowledge, but he who hates reproof is stupid.

To the maximum extent practicable, the Federal Government shall plan missions to accommodate the space transportation services capabilities of United States commercial providers. US law http://goo.gl/YZYNt0

Offline Comga

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Re: SpaceX's Autonomous Spaceport Drone Ship Discussion Thread 2
« Reply #583 on: 01/06/2015 02:45 AM »
Stephen Clark's article over at SFN confirms that

Quote
If the first stage lands intact, sources said the rocket will lock on to the Marmac 300 barge and technicians will vent propellants and toxic substances carried inside the booster before it starts a two-day journey back to port. 
Over on Reddit Musk said the workers would weld the rocket onto the deck. My assumption is that they would weld "toe clips" over the feet, but that the rocket would be safer autonomously.  He stated that the RP-1 would remain onboard "like a jet".
What would safing entail beyond venting the O2, He, N2, and possibly residual TEA/TEB ?
What kind of wastrels would dump a perfectly good booster in the ocean after just one use?

Offline Robotbeat

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Re: SpaceX's Autonomous Spaceport Drone Ship Discussion Thread 2
« Reply #584 on: 01/06/2015 02:46 AM »
From the update thread:

Elon tweeted a pic of the barge enroute

https://twitter.com/elonmusk/status/552182273865699328/photo/1

Taken from air, so maybe camera drone test flight :)

There's no tugboat pushing or pulling it in this picture.  Looks to me like the barge is already station-keeping in this photo.
Nope! Musk specifically said it's heading to its stationkeeping site. The barge is self-propelled.
Chris  Whoever loves correction loves knowledge, but he who hates reproof is stupid.

To the maximum extent practicable, the Federal Government shall plan missions to accommodate the space transportation services capabilities of United States commercial providers. US law http://goo.gl/YZYNt0

Offline Kabloona

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Re: SpaceX's Autonomous Spaceport Drone Ship Discussion Thread 2
« Reply #585 on: 01/06/2015 02:50 AM »
He stated that the RP-1 would remain onboard "like a jet".

You saw that too! It's gone now. https://www.reddit.com/r/IAmA/comments/2rgsan/i_am_elon_musk_ceocto_of_a_rocket_company_ama/cnfqgek

I imagine that's correct, anyway. Why would you bother draining it?

Offline OxCartMark

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Re: SpaceX's Autonomous Spaceport Drone Ship Discussion Thread 2
« Reply #586 on: 01/06/2015 02:55 AM »
For months we’ve been discussing and guessing how the thing would be secured on the barge (Low CG only, heligrid, ropes, sticky trap, etc.) and  whether it would be brought into port vertically or horizontally.  Tonight we have our answer.  And congratulations to *me* for being most right (as judged by me at least).

Bolding added below for my own gloatness

Also notice those relatively smaller blue box on ASDS share same insignia as another pair of blue boxes on ground next to compressed gas trailers, not sure if they are same but looks like same company made them.

Those are absolutely positively Miller brand weldershttp://www.millerwelds.com/products/
Less certain and less important is what in the Miller line they are.  MIG welder?  Stick welder?  Plasma cutter?  Most likely engine driven.

I suppose that they are a normal part of owning and maintaining a ship, or maybe a sign that modifications to the platform are still ongoing.  A more speculative and exotic rumor to start would be that the landing legs have steel foot plates that sit flat against the deck which the securing crew then is able to quickly weld to the deck for the trip back to port.

Edited in second thought: The red vertical pressure cylinders next to the two welders may be to support the welders (Argon, CO2, etc).  If so that's a lot of gas, but I'm not used to working on ship scale welding projects. Or maybe not related to the welders and they are CO2 for fire suppression. Then there's the two horizontal objects that may be connecting the lone welder to the shipping container.  I speculate that that lone welder is being used as an electrical generator to power whatever is going on inside the container, and delving deeper into the low probability speculation pool I'd guess that one of the things in the container is a power distribution panel to all of SpaceX's electrically powered equipment at each end of the ship.

Mark

Question to Elon tonight:
“Mr Musk,
How will you secure the first stage of the Falcon 9 to the barge when it lands? Gravity or some mechanism?”

For Yea Sayeth Elon:
“Mostly gravity. The center of gravity is pretty low for the booster, as all the engines and residual propellant is at the bottom.

We are going to weld steel shoes over the landing feet as a precautionary measure.

Offline Robotbeat

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Re: SpaceX's Autonomous Spaceport Drone Ship Discussion Thread 2
« Reply #587 on: 01/06/2015 02:58 AM »
He stated that the RP-1 would remain onboard "like a jet".

You saw that too! It's gone now. https://www.reddit.com/r/IAmA/comments/2rgsan/i_am_elon_musk_ceocto_of_a_rocket_company_ama/cnfqgek
I thought it was said it before the AMA. I think it may have been at the CRS5 presser today.
Chris  Whoever loves correction loves knowledge, but he who hates reproof is stupid.

To the maximum extent practicable, the Federal Government shall plan missions to accommodate the space transportation services capabilities of United States commercial providers. US law http://goo.gl/YZYNt0

Offline Kabloona

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Re: SpaceX's Autonomous Spaceport Drone Ship Discussion Thread 2
« Reply #588 on: 01/06/2015 03:01 AM »
Best Q&A from Elon's AMA on Reddit:

Quote
Q: What daily habit do you believe has the largest positive impact on your life?
A: Showering

badabump. Now back on topic.

Offline dorkmo

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Re: SpaceX's Autonomous Spaceport Drone Ship Discussion Thread 2
« Reply #589 on: 01/06/2015 03:02 AM »
He stated that the RP-1 would remain onboard "like a jet".

You saw that too! It's gone now. https://www.reddit.com/r/IAmA/comments/2rgsan/i_am_elon_musk_ceocto_of_a_rocket_company_ama/cnfqgek
I thought it was said it before the AMA. I think it may have been at the CRS5 presser today.

i think it was at the presser too

Offline Kabloona

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Re: SpaceX's Autonomous Spaceport Drone Ship Discussion Thread 2
« Reply #590 on: 01/06/2015 03:05 AM »
For months we’ve been discussing and guessing how the thing would be secured on the barge (Low CG only, heligrid, ropes, sticky trap, etc.) and  whether it would be brought into port vertically or horizontally.  Tonight we have our answer.  And congratulations to *me* for being most right (as judged by me at least).

I think Elon actually read your post and said to himself, "Hmmm, that's a good idea."   ;)

Offline dorkmo

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Re: SpaceX's Autonomous Spaceport Drone Ship Discussion Thread 2
« Reply #591 on: 01/06/2015 03:11 AM »
From the update thread:

Elon tweeted a pic of the barge enroute

https://twitter.com/elonmusk/status/552182273865699328/photo/1

Taken from air, so maybe camera drone test flight :)

There's no tugboat pushing or pulling it in this picture.  Looks to me like the barge is already station-keeping in this photo.
Nope! Musk specifically said it's heading to its stationkeeping site. The barge is self-propelled.

Quote
darkmo: So basically you're saying Musk may be lying. I doubt it. The propwash looks like it's coming right from where the thrusters are. Additionally, there's no sign of propwash from the (imaginary, in this case) towboat. Barges are often pushed, not towed, and if they ARE towed, the chains usually are plenty short enough that you'd see the tug in the frame. And even if the tug was slightly out of the frame, the propwash would be clear in the right portion this picture.

not sure but i think (from the one time ive witnessed it) at sea they keep a fairly big distance. also, from the vessel finder data i think they were only going about 5 or 6 knots so i think its possible prop wash could have dissipated by the time it was in the photo frame.

not saying he's lying, just saying its still a little vague. if you see a wrecked car being towed, you could say "its heading to the body shop" :D

also, i think i see a hint of a line coming off the front. perhaps in a Y shape.  just a hint! lol dont hold me too it.

Offline Kabloona

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Re: SpaceX's Autonomous Spaceport Drone Ship Discussion Thread 2
« Reply #592 on: 01/06/2015 03:15 AM »
Except that's not how it's done with ASDS. The tug pushes it.

http://forum.nasaspaceflight.com/index.php?action=dlattach;topic=36326.0;attach=627173
« Last Edit: 01/06/2015 03:16 AM by Kabloona »

Offline Robotbeat

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Re: SpaceX's Autonomous Spaceport Drone Ship Discussion Thread 2
« Reply #593 on: 01/06/2015 03:21 AM »
From the update thread:

Elon tweeted a pic of the barge enroute

https://twitter.com/elonmusk/status/552182273865699328/photo/1

Taken from air, so maybe camera drone test flight :)

There's no tugboat pushing or pulling it in this picture.  Looks to me like the barge is already station-keeping in this photo.
Nope! Musk specifically said it's heading to its stationkeeping site. The barge is self-propelled.

Quote
darkmo: So basically you're saying Musk may be lying. I doubt it. The propwash looks like it's coming right from where the thrusters are. Additionally, there's no sign of propwash from the (imaginary, in this case) towboat. Barges are often pushed, not towed, and if they ARE towed, the chains usually are plenty short enough that you'd see the tug in the frame. And even if the tug was slightly out of the frame, the propwash would be clear in the right portion this picture.

not sure but i think (from the one time ive witnessed it) at sea they keep a fairly big distance. also, from the vessel finder data i think they were only going about 5 or 6 knots so i think its possible prop wash could have dissipated by the time it was in the photo frame.

not saying he's lying, just saying its still a little vague. if you see a wrecked car being towed, you could say "its heading to the body shop" :D

also, i think i see a hint of a line coming off the front. perhaps in a Y shape.  just a hint! lol dont hold me too it.
See, even in your picture, the prop wash from the tug is very clearly visible. No hint of that in the picture of ASDS, just what looks like prop wash from the thrusters.
Chris  Whoever loves correction loves knowledge, but he who hates reproof is stupid.

To the maximum extent practicable, the Federal Government shall plan missions to accommodate the space transportation services capabilities of United States commercial providers. US law http://goo.gl/YZYNt0

Offline Helodriver

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Re: SpaceX's Autonomous Spaceport Drone Ship Discussion Thread 2
« Reply #594 on: 01/06/2015 03:22 AM »
Except that's not how it's done with ASDS. The tug pushes it.

http://forum.nasaspaceflight.com/index.php?action=dlattach;topic=36326.0;attach=627173

Except that when it left the dock it was being pulled, by cable, with the tugboat out front. It can be seen in the time lapse video clip of the port departure.

When barges are moved out at sea they are usually towed by a long hawser cable to provide the least possible stress on the barge and the towing vessel, especially if there are swells that would strain the connections and structure of large vessels lashed tightly together.

I agree that in the tweeted picture at the front of the barge there appears to be part of a towing bridle visible extended into the water, but its tough to be certain with that lighting.

Offline dorkmo

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Re: SpaceX's Autonomous Spaceport Drone Ship Discussion Thread 2
« Reply #595 on: 01/06/2015 03:28 AM »
just noticed large chain on either side. no idea if it'd be long enough to mesh with the tow hypothesis.

Offline CameronD

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Re: SpaceX's Autonomous Spaceport Drone Ship Discussion Thread 2
« Reply #596 on: 01/06/2015 03:30 AM »
Quote
darkmo: So basically you're saying Musk may be lying. I doubt it. The propwash looks like it's coming right from where the thrusters are. Additionally, there's no sign of propwash from the (imaginary, in this case) towboat. Barges are often pushed, not towed, and if they ARE towed, the chains usually are plenty short enough that you'd see the tug in the frame. And even if the tug was slightly out of the frame, the propwash would be clear in the right portion this picture.

not sure but i think (from the one time ive witnessed it) at sea they keep a fairly big distance. also, from the vessel finder data i think they were only going about 5 or 6 knots so i think its possible prop wash could have dissipated by the time it was in the photo frame.

not saying he's lying, just saying its still a little vague. if you see a wrecked car being towed, you could say "its heading to the body shop" :D

also, i think i see a hint of a line coming off the front. perhaps in a Y shape.  just a hint! lol dont hold me too it.

Actually, the giveaway is the bow-wave.  In the high-res pic we see it's still dark (the deck lights are on) and occasional waves show it's pushing into a moderate (but not rough) sea.  If the ASDS was being towed, we'd (a) expect to see some disruption to the wave pattern around and in front - we don't - and (b) the bow wave wouldn't be pushed forwards and upwards as much as it is, since the ASDS would be following in a smoother patch of the tug-boat's wake which extends a long way back even at 5-6kts.

The other thing the bow-wave confirms is that it is indeed a regular shaped barge-style hull under the flight deck - and not the catamaran or SWATH plan-form I'd hoped for...  :(


EDIT:  ..and I'm not convinced the forward thrusters are operating, since the disturbed part of the wake appears to show turbulence consistent with one set of props extending from aft only.
« Last Edit: 01/06/2015 03:39 AM by CameronD »
With sufficient thrust, pigs fly just fine - however, this is not necessarily a good idea. It is hard to be sure where they are
going to land, and it could be dangerous sitting under them as they fly overhead.

Offline Robotbeat

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Re: SpaceX's Autonomous Spaceport Drone Ship Discussion Thread 2
« Reply #597 on: 01/06/2015 03:37 AM »
Quote
darkmo: So basically you're saying Musk may be lying. I doubt it. The propwash looks like it's coming right from where the thrusters are. Additionally, there's no sign of propwash from the (imaginary, in this case) towboat. Barges are often pushed, not towed, and if they ARE towed, the chains usually are plenty short enough that you'd see the tug in the frame. And even if the tug was slightly out of the frame, the propwash would be clear in the right portion this picture.

not sure but i think (from the one time ive witnessed it) at sea they keep a fairly big distance. also, from the vessel finder data i think they were only going about 5 or 6 knots so i think its possible prop wash could have dissipated by the time it was in the photo frame.

not saying he's lying, just saying its still a little vague. if you see a wrecked car being towed, you could say "its heading to the body shop" :D

also, i think i see a hint of a line coming off the front. perhaps in a Y shape.  just a hint! lol dont hold me too it.

Actually, the giveaway is the bow-wave.  In the high-res pic we see it's still dark (the deck lights are on) and occasional waves show it's pushing into a moderate (but not rough) sea.  If the ASDS was being towed, we'd (a) expect to see some disruption to the wave pattern around and in front - we don't - and (b) the bow wave wouldn't be pushed forwards and upwards as much as it is, since the ASDS would be following in a smoother patch of the tug-boat's wake which extends a long way back even at 5-6kts.

The other thing the bow-wave confirms is that it is indeed a regular shaped barge-style hull under the flight deck - and not the catamaran or SWATH plan-form I'd hoped for...  :(
I agree with you totally.

However, I think a persuasive enough argument has been made that it /could/ still be under tow (though I don't believe it, considering the complete lack of any visible sign of a wake from the imaginary tug) that I must retract my "neener neener" until more information comes in that confirms it was under its own power for some of the trip to the station keeping position.
Chris  Whoever loves correction loves knowledge, but he who hates reproof is stupid.

To the maximum extent practicable, the Federal Government shall plan missions to accommodate the space transportation services capabilities of United States commercial providers. US law http://goo.gl/YZYNt0

Offline OxCartMark

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Re: SpaceX's Autonomous Spaceport Drone Ship Discussion Thread 2
« Reply #598 on: 01/06/2015 03:40 AM »
Y'alls fascination with towing, pushing, or self propelled is wasted energy.  You need to get some rest and save up your bandwidth, there is a really big thing happening in a few hours.

Five minutes ago about four posts up was a picture showing 90% of the ASDS at sea from a closer and lower perspective, along with only a few words.  Where did that picture come from?  Where did it go?

I noted a few things on the deck which date that picture as very recent in my mind.  The red man lift device was within the yellow perimeter (on the playing field) and had its extensible legs and neck spread out.  One of the blue welders was on the playing field in the near right corner, there was a person on deck, and there were apparently two painted on circles of ?20 foot? diameter near the far right corner of the deck.

Question about the broadcast tomorrow:
     Will the revolution be televised?

Mark

Offline CameronD

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Re: SpaceX's Autonomous Spaceport Drone Ship Discussion Thread 2
« Reply #599 on: 01/06/2015 03:44 AM »
Quote
darkmo: So basically you're saying Musk may be lying. I doubt it. The propwash looks like it's coming right from where the thrusters are. Additionally, there's no sign of propwash from the (imaginary, in this case) towboat. Barges are often pushed, not towed, and if they ARE towed, the chains usually are plenty short enough that you'd see the tug in the frame. And even if the tug was slightly out of the frame, the propwash would be clear in the right portion this picture.

not sure but i think (from the one time ive witnessed it) at sea they keep a fairly big distance. also, from the vessel finder data i think they were only going about 5 or 6 knots so i think its possible prop wash could have dissipated by the time it was in the photo frame.

not saying he's lying, just saying its still a little vague. if you see a wrecked car being towed, you could say "its heading to the body shop" :D

also, i think i see a hint of a line coming off the front. perhaps in a Y shape.  just a hint! lol dont hold me too it.

Actually, the giveaway is the bow-wave.  In the high-res pic we see it's still dark (the deck lights are on) and occasional waves show it's pushing into a moderate (but not rough) sea.  If the ASDS was being towed, we'd (a) expect to see some disruption to the wave pattern around and in front - we don't - and (b) the bow wave wouldn't be pushed forwards and upwards as much as it is, since the ASDS would be following in a smoother patch of the tug-boat's wake which extends a long way back even at 5-6kts.

The other thing the bow-wave confirms is that it is indeed a regular shaped barge-style hull under the flight deck - and not the catamaran or SWATH plan-form I'd hoped for...  :(
I agree with you totally.

However, I think a persuasive enough argument has been made that it /could/ still be under tow (though I don't believe it, considering the complete lack of any visible sign of a wake from the imaginary tug) that I must retract my "neener neener" until more information comes in that confirms it was under its own power for some of the trip to the station keeping position.

Of course it's possible they cast off the tow only to see how well it performed, take a quick pic for the ravenous public and then take up the tow again. ;) ..but that's not really something you'd do in the dark if you didn't have to.
With sufficient thrust, pigs fly just fine - however, this is not necessarily a good idea. It is hard to be sure where they are
going to land, and it could be dangerous sitting under them as they fly overhead.

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