Steam powered rockets… I once read a SF story (Asimov, I’m pretty sure) about rockets using a reactor to superheated steam for rocket propulsion.
Wheter 19th century technology would be up to the challenge of building such a think (provided some spark of geniality spawned nuclear physics a hundred years early) it would be a possibility. And by a possibility I mean something on the wrong side of slim, being kicked towards none.
They could try machining a large piece of brass roundstock.
I think your guess is correct. Apart from many other problems, the acceleration necessary over the length of a railgun would not be survivable.
A simple projectile wouldn’t have that problem. It would have to be given a velocity considerably above that needed for earth orbit, in order to cope with atmospheric drag on its way to high altitude. That would make pressure-induced heating very troublesome.
But even if you could do it, without radio communications what’s the point? “We fired a projectile with our giant railgun. No one found it anywhere downrange, so it might have broken apart, or burned up, or fallen into an ocean - or possibly have gone into orbit. We’ll never know for sure.”
The ground rules for this little exercise are nebulous to say the least. However, here are some guys who tested a small rocket motor that used paraffin, a little carbon black, and hydrogen peroxide as propellant. The hydrogen peroxide was converted to steam by passing it over a decomposition catalyst, which is conventionally a silver screen. The steam is hot enough (and contains gaseous oxygen as a byproduct) that it ignites the paraffin. The fact that paraffin can function as a solid propellant has to do with droplet formation and gas entrainment at the surface, which unfortunately was not known until very recently. However, if all you’re looking for is truthiness, paraffin + lampblack + peroxide + silver certainly has an old-timey feel to it. The specific impulses they got are in the range of modern solid rocket motors.
I don’t think you would need modern manufacturing methods for the motor case. They were pretty good at barrel-making in the 1880s. With the paraffin layer, and perhaps an insulating and sealing layer of gum-elastic (old-timey!!) the case wouldn’t get that hot. However, the chamber pressure in the tested rockets was 300-700 psi, which might be a little too much for a barrel. The bigger problem would be the nozzle. Not only was the converging-diverging nozzle not invented until 1897, but any materials available in the 1880s would melt, absent some active cooling method, again something that didn’t exist until the 20th century.
You’d also need an injector. I have no idea how this could be done in the 1880s.
I ain’t saying this would work, but maybe it’s enough for your story.
Meanwhile, the British Consulate in Vladivostok is inundated with hysterical locals insisting that a great fiery ball descended from heaven and destroyed their crops, vapourised their cattle, and flattened the tundra forests… 
Thanks. :smack:
Brass has a melting temperature of about 1170K. Space vehicle-class liquid propellant motors have a throat temperature of around 6000K. Most liquid nozzle throats are either ceramic, tungsten, or high temperature superalloy, and often use regenerative cooling to keep the nozzle bell and throat cool enough to survive. Solid propellant rocket engines have a someone lower temperature (~4100K) but experience higher erosion factors requiring the use of a throat ring made some very hard material, either of a tungsten alloy or high temperature carbon-carbon composite. Although you can obtain propulsion at lower temperatures, the resulting specific impulse will be insufficient to achieve orbit, or even a suborbital space flight. There are no nineteen century materials that can handle the required temperatures.
The temperature of the case really isn’t an issue; between the insulating value of a solid propellant (very low heat flux) and insulation/liner between the propellant and the case, you can actually walk up and touch a just-fired motor case and find it to be moderately warm. The pressure, however, is a problem. I don’t have pressure numbers offhand, but modern solid rocket propellant cases are usually proof tested to something like 600-1000 psi (~1.1 to 1.25 MEOP). No barrel maker is going to make a barrel that can retain that kind of pressure, especially at the domes where failure generally occurs. And again, the controls theory and avionics instrumentation that would be necessary to control the vehicle
Technically speaking, a LOX/LH rocket motor is a “steam” rocket, with the steam being produced by the energetically exothermic recombination of hydrogen and oxygen. Of course, there is no way in 19th century technology to produce and store liquid hydrogen or liquid oxygen in any significant quantities.
Stranger
If we’re talking about gun designs, even if you get around the acceleration problem (either with a really long gun or a really durable payload), you still can’t get anything into a stable orbit with just a gun. Basically, you can get your payload into an orbit, but it’s an orbit which intersects the surface of the Earth. And any non-escape orbit which intersects the surface one will intersect it again. If you want to stay up after you get up, then you have to change orbits while somewhere above the surface of the Earth (ideally, at the highest point of your Earth-intersecting orbit), which means you need some sort of propulsion system that you take up with you. The gun does still reduce your fuel requirements, but it doesn’t eliminate them.
Could Pournelle’s downsized Orion design with gunpowder charges instead of nukes be brought to work?
Yeah, a barrel is stretching it. But if they could make barrels, and they could make steam boilers, they might have been able to make some sort of hybrid that would hold the pressure, yet not be too heavy to fly. Plywood with one ply in the hoop direction and one in the axial direction, backed up by steel hoops, might do the trick. I don’t know what the 1880 state of the art in plywood or wood adhesives was.
The aft end of the thrust chamber on the RL10 is just tubes joined by soft silver braze and overwrapped by thin hoops. That can’t be much stronger than plywood and barrel hoops. But I think the pressure down there is only a couple of hundred psi or so, if that.
The OP wants a rocket that can go into orbit, which would certainly require controls more sophisticated than those available in 1880. But if he would be satisfied with a ballistic trajectory with its apogee in space, the required controls would be much simpler, especially if the rocket was strong enough that it wouldn’t need to be steered through the upper-level winds like modern vehicles.
I find this a really thought-provoking thread. Sending a rocket into orbit is clearly possible; the only question is how long it would have taken to do it starting in 1880 with a particular level of funding and a particular required level of reliability. They’d have had to compress a lot of metallurgy, chemistry, and electrical engineering, but they’d only need to develop what was directly necessary for their particular vehicle. The mechanics were well-understood by then. Tsiolkovski laid out all the applications in 1903 but there’s no reason someone couldn’t have done so in 1880. He just happened to be the first person to get interested in it.
I’m going to go out on a limb and guess that with unlimited funding, and very loose reliability requirements (i.e. a lot of crazy bastards willing to fly the thing in exchange for a large sum of money payable to their heirs in the likely event of being blown into hash), it would have taken no more than 30 years. The likely route would have been a solid rocket. It’s just an engineering problem; you don’t need quantum mechanics or relativity to get to orbit.
I’m pretty sure that a manned rocket is right out. We didn’t have the technology to build a pressurized in-atmosphere cabin until after WWI (and WWII?).
I assume that a pressurized compartment only needs to withstand 1 ATM while in space (1 on the inside, 0 on the outside) - and clearly, they were capable of building bathyspheres which withstood greater pressures.
Bathyspheres are easy, though; they’re spherical, which provides inherent pressure resistance, they can weigh as much as you like, since they’ll only have to be minimally buoyant, and they don’t have to be heat- or vibration-resistant.
Wouldn’t that be a solid fuel engine?
Not from inhaling Hydrogen, you wouldn’t. That stuff will give you the deads.
Really? Aside from the fire hazard, is it any worse than helium? That is, you’ll asphyxiate it if you breathe it in and don’t replace it with oxygen some time soon, but it’s not poisonous. Or is there something I’m missing?
Only if it catches fire. Otherwise it works just like helium- actually, it clears the lungs more quickly, since it’s even lighter.
Obviously still not a good idea.
It was a standard test question for engineers in the 19th century to design a rocket to reach orbit, and the correct answer was that it was impossible.
Forget the steam. That’s not a problem. The real issue is fuel. Engineers were assuming coal as a fuel, just like in locomotives. However, when calculating, the weight of the coal needed to provide the energy to reach orbit was too much for the rocket to lift off the ground.
What was needed was a better fuel source. Gunpowder wasn’t good enough, either (especially since a controlled burn was needed). The standard solid rocket fuel wasn’t developed until the 1950s. For liquid propellants, you needed liquid oxygen and I doubt it was available in large enough quantities back then.
I may have been informed (by my school chemistry teacher no less) - I understood it to be toxic or corrosive/irritant when inhaled.
I did some back-of-the-envelope calcs to see how long a railgun would need to be to accelerate a human to orbital speed without killing him. Assuming he can withstand a steady 20g (doubtful, but perhaps possible), the railgun would need to be around 120 km long.
From The Promise of Space, Chapter 6, by Arthur C. Clark, 1968
There was a story about 10 years back of some nutter who’d built himself a steam powered rocket and was planning on launching himself from Central Park, NYC. The FAA was having none of it, however, and the guy was suing, but I guess nothing ever came of it.
German rockets during WWII were powered using hydrogen peroxide, don’t know if that could have been made in the 1800s (and in pure form its really nasty stuff, lethal even).
Someone wrote a story around that time, in which folks sent up a massive pile of bricks into orbit (I think it was meant to be some kind of navigational aid).
For the rocket nozzle, perhaps lining it with some kind of ceramic would work. Such things would have been used as furnace linings and in foundry work, so the concept wouldn’t be foreign to them (unlike trying to figure out how to make a titanium alloy).
If you’re going for unmanned, then why not a variation of Verne’s giant cannon (which was sunk in the ground to prevent the barrel from bursting, IIRC)? Sited atop a tall mountain, it could fire a shell vertically in the air, then have some kind of simple timing mechanism (say one that used the sudden gee forces caused by the gun being fired to drop a weight or break a connection and then ignited a slow burning fuse) which would then kick in a second stage motor of some sort before the shell began to fall back due to gravity.
Say, here’s a thought: The shell has a sabot, which is designed to protect the bottom when the gun is fired, but will quickly drop away once the shell has left the barrel. Inside the lower section of the shell are two seperated chemicals that shortly after they’re combined yield a violent reaction. The force of the gun firing breaks the barrier keeping the chemicals seperated, as they combine, they put pressure on the lower section of the shell, the bottom of which is designed so that it will rupture when a certain pressure level is exceeded. This would give you a second “bang” to kick the shell up higher.