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Curious about your reasoning. I immediately wondered what type of cargo would be suitable for this sort of launch system. I came up with a fairly short list. Fu
by spanktheuser 5y ago
Curious about your reasoning. I immediately wondered what type of cargo would be suitable for this sort of launch system. I came up with a fairly short list. Fuel/water/perhaps food for interplanetary spacecraft destined for Luna or Mars. I imagine one could design some types of cubesats to withstand the tremendous acceleration forces. That was about it.
Is your skepticism based on cargo suitability or other factors.
- NikolaeVarius 5y agoWho the fuck cares about cargo before trying to figure out if any second stage rocket that isn't a rock can reasonably survive the extended application of high G-forces
- robszumski 5y agoThey have some data that indicates most off the shelf electronics survive or need very minor modifications to withstand the G forces. That's better than no data at all but they do have a ways to go.
- mayama 5y agoIt's not just g forces. It's combination of g forces and atmosphere drag. Drag forces during launch could be bigger issue.
- avmich 5y agoSome classification considers 3 types of cargo - bulk materials (metals, fuel); complex electronics; humans. The majority of weight is in the 1st type. Unless first two types have complex mechanical structure, where loads can't be distributed into supports - which is an important issue - the first two groups are candidates.
- jhgb 5y agoBut this launch system still needs the projectile itself to be a fairly complex rocket capable of delivering several km/s of delta V and of steering the payload onto a desired orbit. That still implies electronics and mechanical systems onboard even if you're carrying only bulk cargo.
- avmich 5y agoElectronic chips themselves are rather good to withstand acceleration - can be packaged well. Mechanical systems for simple rockets could also be, well, simple - e.g. first orbital launcher of France used pressure-fed engine.
- panick21_ 5y agoIT make no sense to build a dedicated launch system and non-reusable rocket to deliver a few 100kg max into orbit. A Starship launches 150 tons reusable. That far cheaper and less work then building 500 Upper-Stages and shoot 500 of those rockets with a SpinLaunch system. There is really no comparison in cost. Maybe they could make the upper stage reusable but that would reduce the payload to and even more pathetic amount. This system simply can not compete against reusable rockets.
- Yizahi 5y agoI don't think that even Rh(null) blood, unicorn tears or HP color ink liquids are commercially viable to launch at prices around 10-50k$ per liter. And that if that whole assembly will work at all at prices they are advertising today (1/20 of comparable commercial rockets, but it will have very small payload). PS: I don't have numbers, but I'm guessing that F9 hitchhike Transporter missions cost less per kilogram, compared to the imaginary numbers for non-existing full scale Spinlauch.
- moron4hire 5y agoSkepticism? I'm not "skeptical" about SpinLaunch. I'm incredulous about SpinLaunch. Skeptical implies that I think there might be a chance, if certain criticisms are addressed. No, I am certain there is no chance SpinLaunch will end up being a thing. First of all, putting aside the several red-flags for why this looks like a scam, and assuming it's actually do-able, it's still not going to happen. The global space industry is built on rockets. At best, stuff like this--even if it does work--gets a "cute project, kid" pat on the back and then ignored. When was the last time any fundamental redesign of an existing technology take over an industry? It just doesn't happen. And I think everyone involved probably knows that. You're not going to compete against Google as a scrappy startup trying to make a search engine. You're not going to compete against SpaceX as a scrappy startup trying to make alternative launch systems. Somebody, somewhere, has to understand that. So they have to be in on the scam. Now, as for the actual idea, there are several problems. First and foremost is: energy is energy. If this thing fails, it blows up just as bad as a chemical rocket on the platform. At least chemical rockets are based on decades-old materials science. This spinning arm malarky expects us to believe that they can support 10,000x their payload on the arm and be able to release it on a hair trigger? I suppose next they're going to tell us the arm is made of carbon nanotubes or some other unobtanium. So they want to spin the object in a vacuum. How are they going to seal the spin chamber in such a way that they can generate a significant vacuum while also allowing the payload to escape? They show a paper or some other thin membrane door over the escape hatch that the payload punches through. OK, that means that door needs to be able to support 13.75 pounds per square inch of atmosphere. A 2m x 2m door needs to be able to hold up over 40 tons of atmosphere. The payload needs to punch through a door that is holding up over 40 tons of atmosphere. That payload needs to punch into a 40 ton column of atmosphere. At ~5,000 mph?! So what I expect to happen is that the payload hits the column of air, creates a mach shockwave that destroys all of the windows in a 5 mile radius, while the rush of air into the chamber and clapping back around the tunnel of vaccum the payload creates blinding spike of plasma (not unlike lightning), that ends up destroying the launch chamber. Oh, yes, there are "challenges" to "figure out". From their launch command center that was clearly designed for aesthetics more than functionality. Lots of problem solving gonna happen there.
- XorNot 5y ago
- jjk166 5y agoThe cargo isn't the issue, it's the design. First, you're making a giant spinning thing that contains a ridiculous amount of energy. If the release of the projectile is off by a millisecond, instead of flying through the outlet it's instead flying into the wall of the launcher where it will deliver all of its kinetic energy in the form of an explosion with the energy of about a half ton of TNT, which sounds bad but really isn't compared to the arm its exploding next to that would release the energy of a small nuke if it gets damaged. This isn't a failure mode that can be monitored and avoided; eventually you're going to have a component fail or a software glitch and before the system can even register that something is wrong the launcher will be a crater. You're launching bulk material into orbit where no one cares if the occasional launch fails so long as it's cheap, and you're wasting that on a launch system where the most minor failure results in not just the loss of the launch vehicle but the entire infrastructure for launching. But even if everything works exactly as intended there are still issues. Your giant centrifuge spins up in a vacuum because at those speeds air resistance would be extremely damaging. Unfortunately, after you release the payload, it breaches the seal on the outlet and now you have a giant inrush of air into your vacuum chamber. Unfortunately, the giant arm is still spinning at 8000 kph. The surface of the arm is going to ablate as it moves through sea level air at hypersonic speeds, and its going to generate massive shock waves which are going to reverberate in the chamber. All those precision components for releasing your payload with extreme precision are going to be exposed to these hellish conditions. You're going to need extensive repairs or replacements after every launch. You're doing all this and you still need a launch vehicle with its own rocket engine and propellant, flight control surfaces and surface protection for its own hypersonic journey through the lower atmosphere. Everything needs to survive ridiculous g forces. All this to deliver a few kilograms of low value cargo? These problems don't go away as you refine the technology, they are fundamental. You will always need precision release mechanisms to avoid catastrophic failure, you will always be exposed to hypersonic conditions, you will always experience ridiculous g forces, you will always need rockets for orbital insertion, you will always be restricted to low value cargo. It's an interesting engineering problem; they might learn some cool lessons along the way, maybe some valuable patents will come out of it, but there is no hope for developing a practical space launch method competitive with existing methods.
- 5y ago