RabidMonkey

That's why the formula for calculating Isp from an Orion drive is different - it takes the wasted energy into account. The detonation doesn't have to be as far away as you might think - with no atmosphere, there's no overpressure wave or compression heating. The Project Orion designs called for sub-kiloton yield pulse units, detonating only 25m from the plate. The short duration of the thermal pulse at that range could be handled with a couple millimeters of copper backed with carbon. Plasma doesn't work that way. Unless there is a force causing collisions (like gravity or magnetism), it doesn't collide with itself. For the equation calculating Isp of a pulsed drive, the important value is the initial wavefront velocity of the plasma. My mistake. I was thinking rapatronic camera, but for some reason bhangmeter came off of my keyboard. Like I said, that was an idiot-level design. But think about that - this horrible design can accelerate 123,464 TONS at .01m/s^2. Want to add crew and life support? Fine, add another 500 tons. Acceleration is still .01m/s^2. Want to carry 1000 cows along just for the hell of it? Let's add in another 10,000 tons so we can keep them alive for a while. Plus 10,000 tons of soda because we're thirsty. Acceleration is STILL .01m/s^2.The solid steel pusher plate 2m thick is way overengineered for this. All that's really needed for the actual blast surface is a sheet of copper about 5mm thick that's coated in oil. With that, no plate ablation. The plate is still either flat or slightly concave. I was talking about the shape of the fireball itself when I said "spherical". The best possible fraction with a spherical fireball is .5, and that's if the plate is the same diameter as the fireball itself will be at the detonation distance. Using the copper pusher plate as specified above, we get an acceleration of about 1.4m/s^2. With shaped charges, the plasma can be concentrated into a cigar shape, dumping more energy into the plate as opposed to empty space, giving us fractions greater than .5. Now we're looking at accelerations of over 1g.The beauty of nuclear pulse propulsion is that there really is no practical limit to vessel size. Freeman Dyson was looking at multi-megaton vessels - basically flying cities. There was no technical reason why they would not have worked.

The entire body of the bomb is the reaction mass. For a 1MT detonation, the actual mass that has been directly converted to energy is less than 47 grams. If we take the W53 (America's highest-yield nuclear weapon ever in service - 9MT), then 418.6g of mass are converted to energy in the detonation. That warhead weighed in at 2800kg. That leaves ~2799.6kg which is now plasma moving at ridiculous speeds, because there is no atmosphere to impede it. In a vacuum, the speed of the plasma is proportional to the square root of the change in temperature of the debris. Since this is tens of millions of degrees in only a few milliseconds, the velocity is HUGE. The diameter of the pusher plate then becomes the determining factor for the specific impulse, expressed as what fraction of the plasma will hit the plate, which also depends on the distance from the fireball. So, let's try this with a bog-standard W53 and a pusher plate 100m in diameter, with the explosion happening 1km behind the craft. I can't find any exact figures for temperature other than "tens of millions of degrees", so we'll go with a 15 million degree change as a nice lowball figure. The fireball radius is ~1.2km, giving a surface area of ~1.8e7m^2. Our pusher plate is 100m in diameter, so our fraction is .0004. I also can't find anything noting exactly what is the proportional factor for the temperature to plasma velocity calculation, so I'll lowball that at .01, giving us a plasma velocity of about 1.5e6 m/s, or about .005c. Looking at bhangometer photos of nuclear tests, this feels about right. This (Isp = (C * Ve)/g where C is the fraction and Ve is the plasma velocity) gives us a specific impulse of about 61s. Fairly inefficient in this particular design, but I'm worst-casing everything here, including design (plate much smaller than fireball, distance from fireball, etc). Plugging that into our handy-dandy thrust equation of F=Isp*Mf*g (specific impulse times mass flow rate times g), we get a thrust from a single W53 hitting a 100m plate 1km away of about 1.7MN. That's only 1 bomb per second on a design produced by idiots. Optimize the plate/fireball diameter ratio with a spherical explosion, and the fraction goes to .5. That gives us an Isp of about 76452.6s. Using the same bomb (W53) at the same distance (1km), we now get 2GN of thrust. From one bomb per second. Atmosphere vs. vacuum has nothing to do with it. Atmosphere is actually worse, because you encounter air resistance and compression heating. Look up the Pascal-B test from Operation Plumbbob: A 900kg steel plate was accelerated to at least 66km/s by the blast. It's figured that it didn't actually leave the atmosphere because of compression heating. Strip away the atmosphere, and it would have been single-stage-to-interstellar-space - the Sun's escape velocity at Earth is only 42.1 km/s. Nuclear Pulse Propulsion: Where bigger really is better.

The potential for even more awesome screenshots is about the only benefit I see to this idea.

In an attempt to bring "real life" nuclear engines to the game, I made some configs for the Timberwind Project from the 1990s. Using the stats from the project, they were totally game-breaking. We're talking single-stage-to-Eeloo levels of overpowered.

Live and learn... I had a full base set up on Minmus built around the Hooligan launch pad. Key word here is "had". I put together a ship which was never intended to land, so it needed launch clamps to keep it from falling over. Turns out that the stabilizing clamps spawn inside the collision mesh of the launch pad, making for some pretty pretty fireworks. I probably should have used an orbital launch station instead.

Start by reading the post immediately above yours.

Paste the text into a new file using your text editor of choice, then save it as [whatever].cfg somewhere under GameData. The [whatever] can be any name you like - the important parts are the .cfg extension and the fact that it is somewhere under GameData.

Excellent! Now I just need to worry about having Billy-Bobgas - my resident dangerous idiot - in charge of making antimatter. It's funny... I use MechJeb, so all launches of identical craft should be identical, right? Not if Billy is the pilot. Then I get 400-ton rockets trying to do a barrel roll right off the launchpad.

Does the output rate of antimatter/electrolysis depend at all on the stupidity of the Kerbals in the lab, or is it intended to be a "Push butan -> get fuel" process from their point of view?

With Majir's blessing, my attempt at a balanced Tech Tree integration via ModuleManager: @PART[kethane_1m_converter] { TechRequired=fuelSystems entryCost=0 } @PART[kethane_2m_converter] { TechRequired=heavierRocketry entryCost=0 } @PART[kethane_generator] { TechRequired=largeElectrics entryCost=0 } @PART[kethane_heavyDrill] { TechRequired=advScienceTech entryCost=0 } @PART[kethane_highGain] { TechRequired=scienceTech entryCost=0 } @PART[kethane_kerbalBlender] { TechRequired=advElectrics entryCost=0 } @PART[kethane_radialDrill] { TechRequired=spaceExploration entryCost=0 } @PART[kethane_sensor_1m] { TechRequired=advScienceTech entryCost=0 } @PART[kethane_smallDrill] { TechRequired=scienceTech entryCost=0 } @PART[kethane_tank1mLarge] { TechRequired=fuelSystems entryCost=0 } @PART[kethane_tank1mStandard] { TechRequired=fuelSystems entryCost=0 } @PART[kethane_tank2mSmall] { TechRequired=heavierRocketry entryCost=0 } @PART[kethane_tank2mMedium] { TechRequired=heavierRocketry entryCost=0 } @PART[kethane_tank2mLarge] { TechRequired=heavierRocketry entryCost=0 } @PART[kethane_tank2mExtralarge] { TechRequired=veryHeavyRocketry entryCost=0 } @PART[kethane_tankExternal] { TechRequired=fieldScience entryCost=0 } @PART[kethane_turbine] { TechRequired=hypersonicFlight entryCost=0 } Just copy/paste this into a .cfg file under GameData (I use GameData/Kethane/Kethane_techtree.cfg), and you should be good to go for career mode.

Is there any objection to one of us posting a ModuleManager config that integrates the Kethane parts into the tech tree? I figure that it would be useful for those who aren't inclined to write the config themselves.

As long as all of the parts between the collector and tank are all fuel-flow enabled, you're fine. Learned this when I attached a massive collector array to my tank with I-beams and spent hours trying to get the damn thing into orbit only to find that it did nothing.

You read back 5 posts.

I always treated the roll as the autopilot trying to buzz the tower. It is Mechanical Jeb, after all.

Indubitably. (This 10-char minimum can be a fun challenge when trying to come up with one-word replies )

Turn off your AV.

I'm running both with no problem. Make sure your versions of KSPI, B9, and TreeLoader are all current.Also, please stop using your elbows to type. it's hard to read.

Explosions give extra SCIENCE!

I ran into this same thing. Get the latest TreeLoader off of Spaceport, and it will work just fine.

No, but that's not to say that it lived up to the original purpose for the design: An orbital "truck" where each individual shuttle would be capable of up to 50 launches per year with minimal time between missions.

Seconded. I didn't realize how much I used the parts from this mod.

Updated my TreeLoader to 1.1.2, and all is well. Thanks, and AWESOME mod!

Crosspost from the TreeLoader thread, posted here because it involves the KSPI tree: I'm trying to get MechJeb installed, but it fails to appear as a part. I've tried different settings for "TechRequired" - both Advanced Unmanned (advUnmanned - stock) and Automation (automation - KSPI tree), and I've got nothing. I've also tried adding the parts to the appropriate nodes in the tree.cfg attached to my save file, and still no-go. I'm seeing the same issue with other mods that add parts to the tree, such as B9. Help?

I've got this installed via KSP Interstellar, and I'm unable to add parts from anything else. I'm trying to get MechJeb installed, but it fails to appear as a part. I've tried different settings for "TechRequired" - both Advanced Unmanned (advUnmanned - stock) and Automation (automation - KSPI tree), and I've got nothing. I've also tried adding the parts to the appropriate nodes in the tree.cfg attached to my save file, and still no-go. I'm seeing the same issue with other mods that add parts to the tree, such as B9. Help?

Dynamic Expansion Reactionless Propulsion. The DERP Drive. Upgraded - the Heuristically Enhanced Reengineered Processor - Dynamic Expansion Reactionless Propulsion. The HERP-DERP Drive.