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Although, I guess for something about to go 5000 mph through the atmosphere, a little extra air probably isn't a big deal.
Maybe the hatch cares though.
Earlier quoted context omitted.
I'm still scratching my head thinking of how much force will be crushing the rocket and satellite for an hour. I know space stuff needs to be super durable, but surely the G's it'll experience over an hour will be more grueling than a traditional rocket, no?
To get a rough idea of the numbers if this was a rail gun and accelerating linearly: 1G is 32 feet/second 32 feet /second is ~22 mph They're accelerating to 5000mph so they need to crush things at 1G for ~230 second or just under 4 minutes. If I understand correctly, this would hold for angular acceleration too, since they'd just release at some point. Can someone correct me if I'm wrong?
Take a 200 pound payload, add some rocket to it, let's say 10x the weight to be generous, then spin it in a circle 200 feet in diameter. You're looking at 18 thousand tons of force spinning it at 5000mph. So you're spinning 4 navy destroyers worth of force in a circle, which means you need a latch mechanism that can not only hold that much force, but release it at the exact moment to exit the biggest vacuum chamber ever created through a door that just opened at the right time, generating a mach 6+ shock wave at about 0 meters distance from the door and somehow not destroying it in the process. I don't know that it is impossible, but it is highly improbable. They'd probably have a burst disk rather than a door, because that would let you use the capsule as a bullet to penetrate the exit.
In the article they mention the payload experiencing 10000g, so they must be planning on a circle greater than 200 feet in diameter. I can't find numbers on existing satellites, but I remember reading that rockets typically top out at 6g acceleration and figure on a 10x momentary acceleration due to vibration. To tolerate 10000g the payload being launched will need to be built like a tank, rather than the relatively light current designs. To ease that requirement you could submerge the payload in liquid, but that would decrease your usable payload accordingly.
It would be impressive if they could actually pull it off. I think it would be useful for limited applications. I have watched science fiction shows where mass accelerators could basically nuke planets without radioactive fallout. Maybe this would be something similar.
How does this prevent the satellite from being damaged when it transitions from 5000mph in vacuum centrifuge to less-than-5000mph-in-troposphere 1 meter later just out of the door? That's gotta be one hell of a fairing.
Oh wow, I was wondering why bother building housing around it. That seems incredibly expensive to build and maintain. Your comment is very on point. If they slowly even out the atmosphere, they loose the speed. So they'll need to coordinate the door opening at exactly the right moment. And if it doesn't the whole instillation goes boom. I feel like it would be better just to use the money to buy more rocket fuel at t…
Maybe it's a minor thing, but it's a big tell to me. He says: "My team and I", in the possessive, and to me that always betrays something in founders that I don't like.
The best founders I know usually focus more on the team than on themselves. It's subtle, but I think it's meaningful.
“The reason it's hard to get to orbit isn't that space is high up. It's hard to get to orbit because you have to go so fast .” https://what-if.xkcd.com/58/ Sounds like this solves the easy part (getting to high altitude), but makes the hard part (getting to orbital velocity) even harder.
I think you're imagining that the rocket is fired directly vertically and peaks at some altitude, when the rocket ignite to "make it go fast". Instead, imagine the flings the rocket at a 45 degree angle so when it peaks in altitude it's already going quite fast. As other commentators in this thread point out, it's really an alternative for the primary stage rocket booster part, which doesn't just shoot a rocket strai…
This thing is going to tear itself apart as soon as it leaves the centrifuge.
Earlier quoted context omitted.
> "At this point the spacecraft will be subjected to a peak force 10,000 times greater than Earth's gravity, something opponents believe will seriously affect its structural integrity and the safety of its complex electronics." Centrifugal projectile weapons scale up poorly and have issues even at BB gun scale. Envisioning what happens with a 200lb projectile; leave aside the laughable velocities they're talking, and…
I just assumed they fully expect to pivot into the defense industry.
These kind of forces are pretty insane compared to even the high G boost you get on a normal rocket launch. I wonder if that is going to put a crimp on their potential client list.
Earlier quoted context omitted.
To get a rough idea of the numbers if this was a rail gun and accelerating linearly: 1G is 32 feet/second 32 feet /second is ~22 mph They're accelerating to 5000mph so they need to crush things at 1G for ~230 second or just under 4 minutes. If I understand correctly, this would hold for angular acceleration too, since they'd just release at some point. Can someone correct me if I'm wrong?
You're probably correct, but there is more. Take a 200 pound payload, add some rocket to it, let's say 10x the weight to be generous, then spin it in a circle 200 feet in diameter. You're looking at 18 thousand tons of force spinning it at 5000mph. So you're spinning 4 navy destroyers worth of force in a circle, which means you need a latch mechanism that can not only hold that much force, but release it at the exact…
Earlier quoted context omitted.
I just assumed they fully expect to pivot into the defense industry.
This isn't very appealing to defense either, due to the slow spin up.