this post was submitted on 19 May 2024
102 points (96.4% liked)

NonCredibleDefense

6681 readers
660 users here now

A community for your defence shitposting needs

Rules

1. Be niceDo not make personal attacks against each other, call for violence against anyone, or intentionally antagonize people in the comment sections.

2. Explain incorrect defense articles and takes

If you want to post a non-credible take, it must be from a "credible" source (news article, politician, or military leader) and must have a comment laying out exactly why it's non-credible. Low-hanging fruit such as random Twitter and YouTube comments belong in the Matrix chat.

3. Content must be relevant

Posts must be about military hardware or international security/defense. This is not the page to fawn over Youtube personalities, simp over political leaders, or discuss other areas of international policy.

4. No racism / hatespeech

No slurs. No advocating for the killing of people or insulting them based on physical, religious, or ideological traits.

5. No politics

We don't care if you're Republican, Democrat, Socialist, Stalinist, Baathist, or some other hot mess. Leave it at the door. This applies to comments as well.

6. No seriousposting

We don't want your uncut war footage, fundraisers, credible news articles, or other such things. The world is already serious enough as it is.

7. No classified material

Classified ‘western’ information is off limits regardless of how "open source" and "easy to find" it is.

8. Source artwork

If you use somebody's art in your post or as your post, the OP must provide a direct link to the art's source in the comment section, or a good reason why this was not possible (such as the artist deleting their account). The source should be a place that the artist themselves uploaded the art. A booru is not a source. A watermark is not a source.

9. No low-effort posts

No egregiously low effort posts. E.g. screenshots, recent reposts, simple reaction & template memes, and images with the punchline in the title. Put these in weekly Matrix chat instead.

10. Don't get us banned

No brigading or harassing other communities. Do not post memes with a "haha people that I hate died… haha" punchline or violating the sh.itjust.works rules (below). This includes content illegal in Canada.

11. No misinformation

NCD exists to make fun of misinformation, not to spread it. Make outlandish claims, but if your take doesn’t show signs of satire or exaggeration it will be removed. Misleading content may result in a ban. Regardless of source, don’t post obvious propaganda or fake news. Double-check facts and don't be an idiot.


Join our Matrix chatroom


Other communities you may be interested in


Banner made by u/Fertility18

founded 1 year ago
MODERATORS
you are viewing a single comment's thread
view the rest of the comments
[–] [email protected] 52 points 6 months ago (5 children)

Successful or not, news of the test is a pretty big deal given that it was just a few months ago that reports emerged about China's other proposed super-powered rail gun, which is intended to send astronauts on a Boeing 737-size ship into space (NASA had begun building its own astronaut-shooting railgun in the 1990s, but had to abandon it due to lack of dinero.)

I thought EM-powered launching of fragile things like people was thrown out decades ago. How do you fire something up at high Gs without having high Gs? Projectiles and even some cargo may not care, but people might.

[–] [email protected] 36 points 6 months ago (2 children)

You can launch people out of a mass driver.

They'll die, but you can do it.

[–] [email protected] 27 points 6 months ago (1 children)

If by people you mean "people-flavored slurry", sure.

[–] [email protected] 18 points 6 months ago

We here at Terminal Velocity Aerospace prefer the term "post human product".

[–] [email protected] 1 points 4 months ago

There's an amazing novel series called The Hyperion Cantos where they have these space ships that accelerate so quickly they turn the passengers into goo. Then over the course of the trip the auto-doc regrows the people. Their memories are wiped, so they aren't aware of what is happening to them.

[–] [email protected] 25 points 6 months ago (1 children)

In theory you can launch humans magnetically if you have a really long acceleration track, though I don't think "gun" is really a very good description of such a facility since it's more like a maglev (or hyperloop style vacuum tube train) that gradually rises miles into the air with one end open. Technically possible, but given the costs and difficulty with getting a tall enough structure I'd be fairly skeptical that China actually intends to seriously build one.

[–] [email protected] 2 points 6 months ago (2 children)

Wouldn't have to go straight up, could go along the ground then have a long sweep that turns up

[–] [email protected] 9 points 6 months ago

That was actually the best idea because a long enough length and curve means you can use less acceleration each second. One problem is that to keep it low, like say 3Gs, both the length and curve are huge. Like hundreds of miles. Second is the exit - how high would you have to built it to not open the vacuum tube (it has to be a vacuum to work, i.e. the issues that Hyperloop ran into) and be slamming the projectile with a deceleration effect into the thin air that's left? The numbers have been crunched before, mass drivers on Earth can't deliver breakable things.

Also, that curve would be additional Gs and a lot of technical problems to maintain its path.

[–] [email protected] 4 points 6 months ago (2 children)

Thats what I was thinking of, you still have to deal with building a hugely tall structure though, because the exit must be above the thickest part of the atmosphere

[–] [email protected] 6 points 6 months ago

Most or all of it. To be at orbital velocity the projectile would be moving at 30 km/s. Even a small amount of gases would be a like a brick wall.

[–] [email protected] 2 points 6 months ago

Hugely tall and extremely rigid, because if it wobbles while the projectile is moving through it, it will tear itself apart.

[–] [email protected] 12 points 6 months ago (4 children)

Now someone much smarter than I can do the math, but over a long enough distance with a shallow enough incline on a ramp I dont see why it couldnt be done.

The math might mean the scale of the ramp makes the idea completely unrealistic to build. But I dont see why it wouldnt work.

[–] [email protected] 6 points 6 months ago (1 children)
[–] [email protected] 4 points 6 months ago (3 children)

What does that even mean? Yes, this is a question of physics.

[–] Gullible 3 points 6 months ago (1 children)

8 gs is enough to cause most to pass out. 40 gs is usually going to cause permanent injury. Accelerating on a ramp at less than 40 gs would take a while if you want to reach escape velocity which is like Mach 25. Just mental mathing poorly, it’d be like a mile or two of railgun. Iunno, someone sober do the math.

[–] snugglesthefalse 2 points 6 months ago

Well yeah a lot of the concepts for magnetic accelerators for orbital launches in the past 50 odd years have required 2+ km of ramps to work well

[–] [email protected] 1 points 6 months ago

Mathematically it's possible, like you mentioned. But due to physical restrictions of our planet it might not be feasible

[–] [email protected] 4 points 6 months ago (1 children)

The shallower your incline is, the more air you have to fight through post-launch to get to orbit, during which you're losing velocity. And to get into low-earth orbit you have to reach 28000 kph (17000 mph) because it's not so much about going up as it is about going really fast.

So you need to leave the end of the gun going fast enough to lose speed to air resistance and still reach and maintain orbit. I haven't attempted the math, but it seems like your vehicle would burst into flame going that speed in the atmosphere.

[–] starman2112 1 points 6 months ago

Assuming you don't want to exceed 10 gs, it takes 77ish seconds to accelerate to 7.6 km/s (the orbital velocity of the ISS). It would necessitate a nearly 300 km long railgun. Hypotheoretically it could work, though my gut instinct is that it would require fictionally strong materials to build

[–] [email protected] 8 points 6 months ago

Inertial dampeners

[–] [email protected] 4 points 6 months ago

Yea that’s just bullshit