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Japan Successfully Launches Solid Fuel Rocket (oann.com)
randomErr writes: Japan successfully launched a solid fuel rocket named Epsilon-2. The 26-meter-long rocket launched from the Uchinoura Space Center at about 8 p.m. local time. Japan Aerospace Exploration Agency (JAXA) said this is the latest in Tokyo's effort to stay competitive in an industry that has robust growth potential and strong security implications. Also, this is to curb costs for rocket launches. The Epsilon-2 three-stage rocket [is part of a new generation of solid propellant rockets that aim] to put communication and weather satellites in space.
https://www.nasaspaceflight.co...
It's all there in the summary that you probably should have read before posting so that you don't waste our time.
Much of the cost of a liquid fuel rocket is an engine, here you just have a simple pipe open on one end.
It's all there in the summary that you probably should have read before posting so that you don't waste our time.
Thank you for noticing me, supreme arbiter of the Internet.
You should probably change the word 'our' to 'my' since have it on good authority that other people actually enjoy laughter.
On a related note, does it bother you that the Funny mod is +1 and not -1?
This is news for nerds. Any "nerd" who doesn't think rocketry is awesome should probably turn in their badge on the way out.
Both of you seem to have missed something... that wasn't a joke, these are the lyrics to the chorus of Blue Oyster Cult's "Godzilla", released in 1977. The following lyrics go: "History shows again and again, How nature points up the folly of men". Well it has certainly shown up the two of you.
When you launch it, it will shit bricks
Why are people blaming everything on Trump? He wasn't even elected or running when they started the development on this project.
- These characters were randomly selected.
How could I have missed something? I made the post as a metaphorical tribute to Japan. Perhaps you missed that?
Let's make like a bird... and get the flock outta here.
Why would Japan want such a thing after having avowed a no nuclear policy after being subjected to the only nuclear attack in history? Because Trump has declared S. Korea and Japan to no longer be protected by the American nuclear umbrella.
Yes. So much this! Japan anticipated Trump taking office in 2017 a couple of decades ago and rushed the development of the Epsilon, which first launched in 2013. All of this so that they could have an enhanced version of the Epsilon ready for its first satellite launch in 2016, a couple of months before Trump takes office. Brilliant insight there....
Usually you have to fill liquid fuelled ones up just before you launch them. This means if anyone is observing you, they know in advance that you're going to launch.
This can be a disadvantage for certain applic@.m,mk
no carrier
Confucius say, "Find worm in apple - bad. Find half a worm - worse."
Why are people blaming everything on Trump?
Several reasons. 1) He's an asshole and an easy target. 2) Every president gets both too much credit and too much blame. Trump will be no exception. 3) Trump has said some terrifying and ignorant and irresponsible shit in regards to nuclear weapons which is relevant to this discussion.
He wasn't even elected or running when they started the development on this project.
No but he's the guy who got elected and so his actions and opinions now matter.
Did I say Japan built this thing in response to Trump? Am I claiming that Japan's nuclear reactors (including their plutonium breeder reactors) were built because they needed to make nuclear fuel for their weapons?
Of course not, however if the need arises they will surely turn towards the skills they have peaceably acquired for the production of weapons of mass destruction.
Conservatives are fond of saying that guns don't kill people, people do. Like so many many things in our technological world, (GPS, high purity aluminum alloys for centrifuges, etc.) advanced technological items can be used for many purposes (I do genetic engineering). Now we've got someone who wants to radically alter the balance of power in the world, I would say in a very short-sighted way. So people are looking anew, for their own protection, at what they have and what they can be used for.
mom?
MOM?
MOOOOOOOOOOM!
CLI paste? paste.pr0.tips!
It is, but the fuel on the other hand is very cheap, whereas solid propellants can be much more expensive to process, especially for very big rockets. Anyway, building SRBs is more or less a side effect of having missile-equipped military. You don't look at costs at that point.
Ezekiel 23:20
Why would Japan want such a thing after having avowed a no nuclear policy after being subjected to the only nuclear attack in history?
As far as I can tell, japan has considered to not be a nuclear power almost in name only for quite a while. They have an active space programme, a strong nuclear industry with reprocessing, first world tech and science, active heavy industry, leading supercomputing capability and so on.
Yes, they are avowedly anti nuclear on paper, but when push comes to shove, it's entirely obvious they could have a nuke up in the air with pretty short notice.
Now, while they had a good space program, what they lacked was an excellent delivery vehicle. Liquid fueled rockets are superior in many regards, but as a delivery mechanism for nukes they are not. Solid fuelled rockets are stable, robust, transportable and fuelled and ready to go with no notice 24/7 for years at a time.
Now, there's not been much hurry, but North Korea has been acting more threatening recently, and China is beginning to get a bit miliraristic round that area about ownership of some islands.
I don't think there's a huge desire to become a nuclear power but this sends a message that they could and very quickly if they desired. At this point if Japan felt it had to start it's own manhattan program, well, it would probably be scant months before they reach the stage where they could drop a warhead on more or less anywhere in the world at short notice and from hard to predict locations.
SJW n. One who posts facts.
Solid fuel: Low cost, low storage requirements, quick preparation
Disadvatanges:
Low power, can't be stopped
That's funny.
And the "this could be a missile" take isn't new, nor is it in anyway a response to today's political news.
To the wiki!
So way back in 2012 someone was trying to find out about this rocket, and probably because of its potential as an ICBM.
But yeah... because Trump.
Oh, and whoever modded wisebabo offtopic is a little slow.
The adaptation of the solid rocket boosters from the HII-A into a stand-alone rocket has always had military implications. I don't think anyone is pretending otherwise - at least not with more than a fig leaf.
Just because his tack-on attack on Trump was silly doesn't make discussions of the possibilities as an ICBM offtopic.
US ICBMs are solid fuel rockets. This is so they can be launched quickly before an attack by an adversary can take them out.
That said the primary design goal for this particular rocket is low cost. One of these particular rockets costs only $38 million. Many launch systems aimed at putting about 1000 kg into orbit are solid fuel because it's relatively cheap to build and operate a solid-propellant rocket and you don't need to squeeze every last bit of specific impulse out of the rocket to launch a modest payload.
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Post may contain irony: discontinue use if experiencing mood swings, nausea or elevated blood pressure.
While solid fuel is not normally considered a good propellant for commercial launch operations, it is very good in case you ever have to field your own ICBM's. With The Donald talking about shaking things up with our allies (saying Japan and South Korea should have their own nukes), this is good expertise to have experience with.
Thank you. That "article" is one of the worst things I have ever read, the only saving grace being that besides being completely contentless it was also short. And why are we driving eyeballs to this unknown newsrag anyhow?
This article, from your link describes the first Epsilon launch in 2013 and generally the development projects which led up to it. Quoting the overview:
I'm not particularly sure why this is news, but especially puzzled at the choice of headline. This is apparently the second Epsilon launch, but not exactly JAXA's first time on the ranch. It's their fourth launch this year, and the next one is in mid-January. It must be a slow news day. Anyhow, for anyone else's further purview, the Wikipedia article on the satellite it's launching is here, and it could perhaps be considered a replacement for this one which was deactivated in 2015.
Those who advocate genocide deserve every protection afforded by law, and none afforded by common human decency.
Sorry, I guess what I wrote could be interpreted in the wrong way:
"Why would Japan want such a thing after having avowed a no nuclear policy after being subjected to the only nuclear attack in history? Because Trump has..."
I guess I could have been more clear: "Why would Japan want to use it in such a way after having avowed..."
As someone who been following national space programs for decades (and regularly attended JPL conferences), it was not my intent to say that Trump was responsible for Japan's solid rocket program (as if). Nitpicking aside, my apologies for the confusion, however the rest of my points (repeated I see by numerous other commentators) stand.
From my limited KSP playing experience, the biggest drawback for solid fuel propulsion is the inability to throttle back (or shut down) the rocket.
I have seen a growing number of non-booster stages that use solid rocket fuel systems. Has this problem been solved?
As commented above, the article at:
http://spaceflightnow.com/2016...
notes that all 3 stages are solid propellant systems.I see no mention of liquid propellants, though there may be some for the spin-up and station keeping.
If this really is a completely solid propellant system, the cost savings would be incredible. One number I saw was 1/3 the cost of traditional systems. At least for earth orbit, that should give the Space-X crew some competition for a while - which is good for everyone.
BoC's Godzilla is a highlight of Rock music, amazing the original AC in this thread didn't get that.
History shows again and again
How nature points up the folly of men
Godzilla!
The shepherds did so well protecting the flock that the sheep no longer believed that wolves existed.
How could I have missed something? I made the post as a metaphorical tribute to Japan. Perhaps you missed that?
Some AC's ain't got it going on. Hard to imagine he didn't get the reference.
The shepherds did so well protecting the flock that the sheep no longer believed that wolves existed.
Why on Earth anyone would make a rocket out of solid fuel is beyond me. It seems unnecessarily hazardous and I don't understand the benefits. Are they gonna sell it to the Russians for giggles?
Solid fuel is more stable.
You don't have to fuel right before launch, lose a lot of the fuel and Oxidizer during the runup to launch, and then have to pump it back out if the launch is scrubbed.
It's really handy for first stage boosters. If you want a lot of boost, a rocket like the Saturn V has to have incredible amount of thrust just to get off the ground. Strap on a couple solid boosters and suddenly you can save the liquid fuel for later in the flight when the throttleability that solid fuel lacks is more needed for precise orbit injection.
The shepherds did so well protecting the flock that the sheep no longer believed that wolves existed.
It would seem that technology enthusiasts who have an interest in information systems don't have a strong desire to read about rockets posted on a website that used to be dedicated to news about information systems.
If you look at the top of the page, there are many things that Slashdot is about. Technology is one of them.
And this is technology, and this is of direct interest to many of us - myself included.
I mean it isn't the level of interest of Vim vs emacs arguments always bring us, or the ever enjoyable password arguments, but some of us have a passing interest in rocketry.
The shepherds did so well protecting the flock that the sheep no longer believed that wolves existed.
It is, but the fuel on the other hand is very cheap, whereas solid propellants can be much more expensive to process, especially for very big rockets. Anyway, building SRBs is more or less a side effect of having missile-equipped military. You don't look at costs at that point.
There is some pretty solid science and technical reasons why a strap-on SRB is a more cost efficient way to go than designing and running a liquid fueled rocket capable of running the whole mission.
Especially that first few thousand feet.
Do you have any references to solid fuel boosters being more expensive to process than the compression and storage and pumping and evacuation if needed of the liquid fuels? I assume that you are speaking only of hydrogen/oxygen fuel, not the hypergolics or highly refined kerosene fuels.
The shepherds did so well protecting the flock that the sheep no longer believed that wolves existed.
Actually it's not perfect for satellites (and much worse for manned missions, remember Challenger)
To be precise, the Challenger accident was caused by operating the SRB's out of their design range. While they were not supposed to be used at less than 50 degrees, the night before the launch, the temps dropped to 18 degrees F, and were still below too cold at launch. The joint seals did exactly what the were expected to do when launched out of design window.
It was one of those cases of humans trying to trump physics with the suit's decisions.
The shepherds did so well protecting the flock that the sheep no longer believed that wolves existed.
Solid rocket motors have tradeoffs. In some circumstances, they make sense.
They are long-term storage-stable. Build it, stick it in a silo somewhere, and leave it be for a few years, it will still launch just fine. Hypergolic liquid-fueled rockets can't be kept ready-to-launch for more than a few days*, and cryogenic liquid-fueled rockets can't be kept ready-to-launch for more than a few hours. This makes them particularly preferable for military uses, everything from little anti-tank rockets to ICBMs. This also reduces the number of ground crew needed - you don't need to worry about fueling, just electricals and signals.
They have extremely high levels of thrust, due to the extremely high energy density. The Shuttle's SRBs were each twice as powerful as the largest liquid-fueled rockets. This makes them very popular as boosters.
They have a lot of impulse per unit volume. What most rockets care about is impulse per unit mass (aka specific impulse), but some cases care about volume. If you're launching from an aircraft, like Stratolaunch or Pegasus, this matters. If you have constrained volume because you're in a fixed-size fairing, this matters. If you're launching from a submarine, this matters.
It's also often a matter of economies of scale. Countries with military missile programs (which have many reasons to go solid-fueled) often use them for other things as well, either to subsidize their military-industrial complex or to take advantage of existing scale to make civilian rocketry cheaper, depending on how cynical you are. The US, masters of solid-fueled ICBMs, used a pair of massive SRBs on the Space Shuttle, and will use them again on SLS, if that ever flies. The ESA's Ariane 5 uses SRBs based on a French SLBM. Japan may not field ICBMs, but they too have a reason - the first stage of this rocket is almost identical to the booster of their H-II rocket.
The higher stages are solid-fueled presumably to maintain that low-ground-crew capability, and the minor reduction in drag can't hurt either.
I think Rockety is awesome when it's done by NASA and not con-artists that cut corners with safety to make a buck.
So you prefer rocketry in the form of a Rube Goldberg contraption that's so unwieldy that safety corners have to be cut in order to make any attempt at a launch.
Blue Oyster Cult had two songs worth listening to and "Godzilla" wasn't one of them.
Apocalypse Cancelled, Sorry, No Ticket Refunds
Cheaper, they have less parts and don't have all of the headaches associated with handling cryogenic fluids. Only their 4th stage uses liquid propellant, hydrazine a monopropellant. Having a 3 stage solid propellent stack is actually quite an achievement.
Apocalypse Cancelled, Sorry, No Ticket Refunds
They wouldn't even need a nuke, 350Kg of scrap iron in a reentry vehicle coming down from 20,000 mile up is going to hit the ground like one. It would be more than enough to pound N Korea's nuclear program into oblivion.
Apocalypse Cancelled, Sorry, No Ticket Refunds
Only cryogenic fuel rockets. Hypergolic fuel rockets can be fuelled way earlier - the missiles can stay fuelled up to a decade or so.
"It's such a fine line between stupid and clever" -- David St. Hubbins, Spinal Tap
Usually you have to fill liquid fuelled ones up just before you launch them. This means if anyone is observing you, they know in advance that you're going to launch.
This can be a disadvantage for certain applic@.m,mk
no carrier
Yes, but I think they will know you are launching when you go stand this thing up on the launch pad and fuel the second and third stages.
Enigma
As commented above, the article at:
http://spaceflightnow.com/2016...
notes that all 3 stages are solid propellant systems.I see no mention of liquid propellants, though there may be some for the spin-up and station keeping.
If this really is a completely solid propellant system, the cost savings would be incredible. One number I saw was 1/3 the cost of traditional systems. At least for earth orbit, that should give the Space-X crew some competition for a while - which is good for everyone.
I agree that this could be a cost-efficient way to get to orbit, but it's not competition for the Falcon 9. This launch boosted a 365 kg satellite into GTO. The Falcon 9 can boost 8,300 kilograms into GTO. The Epsilon costs $38M per launch, so for this launch the cost to orbit was about $104K per kilogram. The Falcon 9 costs $62M, so for a max payload mission it would cost about $7500 per kilogram. They're not even in the same ballpark.
Enigma
There is a political aspect to it. Solid fuel rockets are ideal for ballistic missiles because they can be kept on standby with little to no maintenance. This is a dual-use technology that means Japan could produce intercontinental ballistic missiles if it wanted to. This is the exact thing North Korea was forbidden to do by the UN.
Of course more whining from North Korea is not likely to be noticed, but it won't help relations with China either.
It'd leave a big hole, but it's not even close to a nuke. If you can aim it well enough, it's still good for precision strikes when you just want to blow up a single facility without having to deal with air defense.
The sane high-thrust booster choice is RP-1/oxygen or even CH4/oxygen these days. Indeed I'm speaking about the fuel cost. Liquefying oxygen or methane per unit of mass is pretty much the lowest-cost thing one could come up with - below one dollar per kilogram for sure. Mixing a heterogeneous mixture of solids and curing it in a casing is definitely more expensive. Apparently, the cost is something like 50 Euros per kilogram for Ariane 5 boosters. Now that's of course meaningless if the liquid rocketry gadgets are as expensive as it they have been until now, and for many systems, I'd expect an SRB to be preferable for the "initial kick" , but with engines like Raptor or BE-4 on the horizon, this could change.
Ezekiel 23:20
I have a hard time agreeing with that. I'm not a rocket scientist, but I think there are a number of things which detract from that argument. The principles of solid fuel rockets are pretty solidly nailed down, especially in terms of chemistry, and while solid fuel does have certain conveniences, ballistic missiles can run just fine on alcohol, jet fuel, kerosene, or whatever is lying around. Almost anyone could produce ballistic missiles, it's a lot easier than putting something in orbit. JAXA building one solid fuel rocket every two or three years is not actually equivalent to having the ability to manufacture ballistic missiles en masse. Turns out, you build missiles differently from rockets, which might explain why they have different names. Playing around with KSP will probably give you the most insight into the kind of structural differences you would need to adapt this technology, but rockets tend to be fairly precisely designed around mission requirements, so if you change those drastically you would still need to re-engineer your rocket significantly. Also, it's extremely unlikely that they were manufacturing this with mass production in mind (i.e. hundreds at once) so that capability would also need to be developed. Also, one of the fun features of solid fuel rockets is that shutting them off once you turn them on can be a challenge, so anything that's going to supply you with the velocity to reach orbit is going to be complete overkill if you happen to not want to do that, so you can't just slap a warhead on top of this rocket and call it a day.
This could be considered a starting point for a ballistic missile program, but so could a copy of John Clark's Ignition!. The problems of ballistic missiles and of orbiting satellites are not as similar as they might appear, and in no sense could these rockets be considered "dual use". And remember that thing where the US did the reverse, trying to turn Redstone ballistic missiles into orbit-capable launch vehicles? Here's a list of Redstone launches. Note that the word "failure" occurs 80 times in that list, and Redstone was considered a reliable rocket. So essentially rocketry is difficult, and this should not be considered a strategic move. It might be useful for some political purpose to pretend that it is a strategic move, but I tend to doubt that as well -- as you say, if it's just NK that gets upset no one will care.
Those who advocate genocide deserve every protection afforded by law, and none afforded by common human decency.
Your thanks is appreciated supreme arbiter of rocketry.
Indeed, but normally it take a little more than acting like a complete idiot to make them laugh instead of just writing you off as a complete idiot.
your right, my back of napkin says about 5 ton of TNT. I assumed that because a 1/4 inch of rain on NYC releases a 1/4Kt that it would be higher.
Apocalypse Cancelled, Sorry, No Ticket Refunds
Indeed, but normally it take a little more than acting like a complete idiot to make them laugh instead of just writing you off as a complete idiot.
Bob, we've already established that you are more of a Krampus than any authority on humour, so this just comes off as sad.
Are you grumpy because people around you are happy during the holidays?
... That Japan has stopped assembling checklists of things to do to build a rocket (then firing them off and finding that things seldom go to plan) and actually started testing every step of the way as well as taking input from the rank-and-file workers (This was one of the prime causes of past failures. Lowly workers would notify that XYZ was incorrect but be overruled by managers who knew better because they were highly paid managers, not lowly workers who actually put the things together(*))
(*) This culture was one of the prime contributors to Fukushima occuring. GE consultants told Tepco management NOT to put the generators down by the plants during the construction of the site because of the risk of flooding if there was a major tsunami. Tepco management smiled and nodded - and put the generators there anyway, because they knew better than the (non-management) consultants.
Solid fuel rockets are generally less dangerous than liquid-fuelled ones (until you light them).
As first stage boosters they're quite useful lifters but I wouldn't want to go to orbit on one.
"Hypergolic fuel rockets can be fuelled way earlier"
Those tend to be something you don't want to spend any time in close proximity with. Hypergolic fuels and biologicals tend not to make a good combination - and unlike space, metals tend to corrode when in an atmosphere so the risk of long-term leakage is substantial.
"Apparently, the cost is something like 50 Euros per kilogram for Ariane 5 boosters. "
The higher cost of the materials is more than offset by not needing to have pesky expensive things like turborocket engines at the blunt end.
As for the ESA published cost, having worked on the peripherals of the organisation for the last 15 years I could easily believe that figure being 20 times higher than the ACTUAL cost of the material and manufacturing, based on inflation of figures as they pass through the organisation.
If SLS wasn't a rube-goldberg contraption, a leaky O-ring wouldn't have mattered other than causing a slight asymetry in the thrust.
if SLS wasn't a rube-goldberg contraption, a bit of shedding tank insulation wouldn't have gone anywhere near the flight surfaces of the actual spacecraft.
If you were to launch a solo SRB with a capsule on the end at 18F, noone would even need to worry about leaky o-rings, other than the risk you'd need more fuel burn in your final stage to achieve the desired orbit height.
Even with the originally designed liquid boosters, SLS would have been a rube-goldberg contraption.
The higher cost of the materials is more than offset by not needing to have pesky expensive things like turborocket engines at the blunt end.
The single most important reason for those "pesky expensive things" to still be peskily expensive in the 2010s is that nobody cared about making them cheaper, both in terms of manufacturing and in terms of being able to use them multiple times. Now that companies like SpaceX and BO started caring about these things, there's very likely a shitstorm coming for the legacy designs.
Ezekiel 23:20
I clearly had no way at all to be able to tell the difference between you acting like a total idiot in a failed attempt to be funny or merely being one of the many "it's not US space so let's dump on it without having a clue" losers.
Please keep that in mind the next time you attempt to be funny but fail so dismally.
Also why are you trying so hard to convince me you were joking?
Grumpy? From the guy making an attack on JAXA or pretending to do so?
Now you are making me laugh - what a loser!
When it comes to liquid fuelled ballistic missiles, they usually are factory fuelled (UDMH + RFNA) and are stored that way for "fucking years, absolutely years" and don't leak (that's why they were so expensive to build). And when the ballistic missiles approach the end of their warranty, they can be used for satellite launches.
"It's such a fine line between stupid and clever" -- David St. Hubbins, Spinal Tap
I clearly had no way at all to be able to tell the difference between you acting like a total idiot in a failed attempt to be funny or merely being one of the many "it's not US space so let's dump on it without having a clue" losers.
Please keep that in mind the next time you attempt to be funny but fail so dismally.
This is something you should take up with your grade school teacher and/or parents. I claim no responsibility for your Trump-grade intellect.
Also why are you trying so hard to convince me you were joking?
Because your saltiness amuses me.
Bob, you aren't making yourself look better here. It's bad enough to be Krampus, don't be illiterate too. Nobody wants to hug a kid that special.
Also, you don't have to answer twice to my posts. I get that you need to rest between these intellectual exertions, but it's possible to just save the first response to a text file and then load it up when you have rested.
You're welcome.
You are still trying?
Where the fuck was the joke? It looks to me that you just didn't read the summary and wanted to have a go at a rocket scientist to inflate your ego?
WTF is your problem kid? What's with the hate of JAXA?
Why not - you replied twice to my initial post after all.
Just admit to yourself that you fucked up by not reading the summary before writing your petty attack on JAXA and then later pretended it was a joke to avoid looking like the idiot you are. No need to admit it to me since I worked that out from the start.
WTF is your problem kid? What's with the hate of JAXA?
Bob, the only hate here is between you and humour.
Admittedly, you are far better than any joke I could tell, so in that regard you have me beat. Well done.
I think we've already covered your personal war on literacy, no need to rehash.
Or you could figure out that very few people are so insecure that they would need to lie on a pseudonymous forum. Your projections onto me serve only to embarass and, were this not a pseudonymous forum, humiliate you.
Not as such. Your bluff didn't work loser.
So slang guy is referring to literacy? It appears you only have one card to play even when it is ridiculously inappropriate.
It didn't look like a lie, it looked like full on jingoistic stupidity and despite your backpedalling I think that is what it was since there is not the most remote trace of humour in that first post. The lie comes later with your backtracking and your pointless attacks on me just because I politely pointed out your stupidity.
How the hell do you cope if this is all it takes to set you off with the "Bob", "Krampus" and "special kid" stuff? Shouldn't you be taking your medication if you are really that fragile?
I guess I could have been more clear: "Why would Japan want to use it in such a way after having avowed..."
So you anwered a question that wasnt asked, while pretending to answer the question that was....
Got it. Dishonest fuck detected.
"His name was James Damore."
Haha, you're doing it again. When you grow up you'll understand.
Slang and literacy go quite well together - in both directions one should understand one to fully appreciate the other. Only a special kind of child would fail to make that connection...
Other than that, It's not surprising that the boy who hates laughter would find stuff to be "ridiculously inappropriate".
Your are just adorable.
Bob, calm your tits.
I don't want you to get a heart attack. You are my Slashdot entertainment for the time being and I want you hale and flailing.
You're quite right, but the engines are still expensive enough that virtually all the new designs are centred around getting them back for re-use.
If they're basic and cheap enough you can treat them as disposable, but noone is brave enough to make a Sea Dragon (which is reusable anyway).