On Orbit Orion Construction

Open discussion on the Internet about the history of the Orion Project has encouraged some preliminary revisions. “On Orbit Orion Construction” is a popular one. Finally some realism on what is acceptable in the world today. The ground launch option was fine as an idea back in the late 50s but today is a non-starter. If “Orioneers” cannot move forward together from what is almost an "article of faith" from the original program, I can see no chance of any politician ever even vaguely considering it. I will shortly explain in detail why.

The next article of faith that “Orioneers” will have to abandon is the "pusher plate". No tears please. There is no word in the English dictionary for a hollow tube with a pusher plate attached on the end of it, except the word “cannon”. Technically a cannon or even a rifle is a pusher plate with walls on it. This is a far more likely bet for a successful outcome, and I will explain why. Firstly, do try and not automatically assume it would shatter into millions of pieces under the force of the explosion. On what do you base your assumption? There would be no atmosphere plug or pressure to impede the escape velocities of the critical mass residues. Space is a far more favourable environment for success precisely because everyday stress forces such as gravity and atmosphere are cancelled out from the equation.

OK it is a good step that some Orioneers are prepared to begin modernising the project parameters with an orbiting space test in place of a ground launch. I would say that around 100 space tests could be held before continued failure would force abandonment. This is because there would be a percentage launch failure of the rockets taking up the fissionable material and that would cause some atmospheric and ground contamination. Even a 5% payload launch rate would be 5 scattered warheads, although not detonated, within our biosphere.

This gives me a chance to introduce a new term "payload launch maturity". That is to say an orbiting built Orion depends on a very low failure rate of chemical rocket launches. I would speculate we reached that maturity perhaps a decade ago and that we are now perhaps going backwards because the space program has run out of energy and direction. Of course to build Orion in space would require maximum payload lifting rocket launches (100 tonnes each) and payload launch maturity percentile statistics would need measuring against this heavy duty lifting expectation of existing and to be improved chemical rockets.

It would cost tens of thousands of astronaut man-hours to assembly in space and the ability to keep the wage rates of astronauts moderate would be important to overall budget projections. Not something we are used to at present.

One way of thinking about it is to imagine trying to build an actual steel-works in space. This parallels the European history with the Chinese development of gunpowder and the time lag before European engineers could use metalworking skills to build a cannon in one piece. That is another reason I am against a "pusher plate" compromise. Once you start abandoning physical containment of an explosion within a tube, you abandon the entire historical path of firearms development. From 900AD to the musket, to the rifle and First World War big guns, everything depends on the pusher plate having walls. Many machine gunners died in the First World War because their machine guns overheated and exploded. Things are always being learnt and improved upon.

I thus find it frankly ridiculous that Orioneers then are forced into discussing vending machine company ejection systems etc. The precedent is called the shell casing. When you fire a machine gun the shell casings are ejected everywhere, but the gunpowder was in that casing to protect the gun barrel from degradation. That has been renamed ablation of the pusher plate in Orion speak. Why re-invent basic principles when there exist centuries of development? Your answer is probably that the explosion is too big. Bearing in mind my beginning note on the different stress forces in space, do not assume this. Nothing has been tested so nothing is known. What I do know is that history clearly shows the Chinese failed to take military advantage of their gunpowder. Their first cannons were primitive and they fundamentally could not successfully apply their designs for much purpose because of continually fears about them exploding. My point is that the inventing nation of a new explosive material in the past, failed to exploit that potential. A fear of a new explosion, held back from its destiny, mainly out of fear and superstition. Ring any bells?

When talking about building in space, remember that you only need to build the first one. After that attach a few ropes and you can use it to yank into space whatever weights you want. Obviously the first yank (elevator pull-up) is more of the same. The allowance of 100 tests is that it takes this amount of time to successfully build the first one. By success I mean the explosion is 100% contained and as a consequence 100% of the force is transferred into forward motion. Of course that then demands reverse thrust chemical engines in space to slow it down, stop it and return it for inspection. You can see a simple sketch on my website.

It might well be just like Eddison testing a light bulb. Each test could be made with different containment materials, both in terms of the cannon and in terms of the shell casing surrounding the critical assembly. Provided the shield is good enough one could theoretically test bamboo and the test pilot would be safe. Of course each test would require the refuelling or top-up of the chemical reverse thrust engines and that would be expensive in terms of astronaut labor hours. However if you fail at test number 100, at least the reverse thrust chemical engines could be uncoupled and used for a traditional Mars trip. The engines are going to have to be very large anyway to counter the fission force conversion at 100% so they would be very suitable for high-speed enabled trip to Mars. After all the failure it might be a saving grace of the project for politicians to appease the public with.

On Orbit Orion Construction continued

However physical containment in the cannon might work first time around. Who knows? Perhaps Eddison could have picked the right filament material for the light bulb first time round. I estimate the cannon alone would be a maximum of 500 tonnes of steel or carbon-steel. I also then guess it could then pull into space 20 times its own body weight if it were working properly. So this is your genuine, no-nonsense, space elevator (ACCTOPE Atomic Chemical Counter-Thrusted Orbiting Payload Elevator) with the ability to yank into space cargo of 500 x 20 = 10,000 tonnes. Even if you set your project ambitions within the framework of inherent low “real” economic returns from our potential solar system exploration, the alternative use of Orion as a heavy duty payload elevator would have vast economic benefits. Build the first one and you can drag up even more. What's more it can operate from any orbit so space industries could be run from places such as the United Kingdom which are way off the equators.

If you are still determined to stick with the pusher plate despite my argument, answer me this. Who is going to pay to compensate all the commercial satellite owners when the first uncontained explosion in space sends an EMP (Electro-Magnetic Pulse) racing unrestricted around the heavens? Would that most likely not destroy in one fell swoop over 50% of all orbiting satellite electronics? You yourself may be off to Saturn but you leave behind a world devoid of any satellite communications!

Even with Orion using a cannon design rather than the simple pusher plate, it would face the same problem if the first test did not “contain” successfully. The risk of not achieving 100% containment on first attempt would have to be insured against and that could be the biggest obstacle to the Orion project. Those advocating the legacy of Orion seem to forget it was envisaged in an era when commercial satellites did not exist.

The EMP argument then might then degenerate (see my website) into a very cynical discussion. If, for instance, the world had two competing SDI shields, then if they were to clash “accidentally” all the commercial satellites could be eliminated. That would allow any type of Orion testing in space to proceed and evade all compensation costs. The danger, which is why it is not the preferred option, is that the losing side in the clash of SDI shields might not choose to surrender. Even if it meant there remained no way to protect themselves from the winner's ballistic missile launches. That would be a very dangerous end game.

Orbit Orion Construction is in itself not a big enough compromise to modernity. The pusher plate has to go back to the drawing board and look at how a simple addition of tube walls to become a new type of cannon that would work in space for peaceful means. That immediately brings in the challenge of physical containment. The pusher plate is in itself actually disingenious as it deliberately shirks the challenge. Thus it rejects the tried and tested development path of over a thousand years in length. Of course it is a new path in terms of we would be borrowing the word cannon to use in space for peaceful terms, or an elevator or planetary tours. While ablation is going to be a challenge whatever, with a cannon you can use cartridges or shells to reduce it to zero. The continued challenge is therefore containment itself, not to think of clever and disingenuous ways of it being evaded. This is an issue which terrified the Chinese back in 900AD and is still in the back of the mind of anyone who has ever shot a rabbit with a shotgun. The perceived risk in containment will always be there.

Unless advocates of the pusher plate can deal with EMP and de-satellisation issues, any such proposal would be thrown out of any funding appraisal committee. That is regardless of whether it is a ground launch or an orbiting construction. However for me the ground launch is simply the ultimate resort. I mentioned at the beginning of my post that one should try and imagine a steel works being built in space, I did just that. I called it HMS Sheffield. Sheffield is a famous steel town in England from our heavy industrial period.

Conceptually, HMS Sheffield “space station” is the point at which one imagines reaching 100 atomic space cannon test failures. The only hope then remains that the 500 tonne cannon be built in one piece on earth. All previous efforts to build it out of several pieces, necessary because nothing that heavy can be put into orbit in one piece using chemical rockets, have failed. HMS Sheffield is then a concept that surrenders development to future generations. A dream that one day a steel works in space could be built and that from that future generations would build the cannon in one piece. Attempts at containment however in the present are abandoned because global economies are exhausted with meeting these development costs and public anger at the 5% rocket payload contamination impact is growing.

It is only at this point that the original Orion ground launch plan works for me. It could still well be a cannon rather than pusher plate, unless there is a good reason why atmospheric and gravity forces might prefer a pusher plate design. There might be as yet unforeseen reasons why a pusher plate works in a gravity atmosphere while a contained tube-cannon works better in space. However it would be a one-off ground launch, purely utilizing the heavy payload capacity of the Orion concept to carry into space the originally required "one-piece" 500 tonne cannon. Whether it could do so and not advance as far into orbit so as to EMP kill all the satellites is another question altogether.

Until Orion moves into this ground of ACCTOPE and presents the project as of limited danger to existing satellite systems investment, I cannot see it being taken seriously. This makes economic and political sense in a way that a ground launch never could.