Is the ol' Boom Boom overpowered?

[MedwedianPresident]

I came across this mod (https://kerbalstuff.com/mod/1175/Nuclear%20Rockets) a few weeks ago, and I succesfully sent a giant probe (launched using 7.5m parts) onto an interstellar trajectory (using the Oberth effect, previously sending it into a Kerbol trajectory with an extremely low periapsis.

Now, I have started to wonder whether using this mod is considered "cheating".

PRO:

- The Orion drive allows for quick acceleration while a large fuel reserve is accessible; far targets that otherwise take months of planning and designing complex interplanetary missions can easily be reached.

 

CONTRA:

- Extremely high G-Forces that are not constant may cause for crew transportation to be extremely complicated (Pancakes made out of Kerbals...yummy!).

- Actually putting the thing into space is extremely hard. 5m+ stacks are required.

 

What are YOUR opinions to the following questions:

 

- Is using the Orion drive considered "cheating"?

- Is it allowed in the late part of a career game or while playing with a high technology level / recreating Sci-Fi missions in sandbox?

- What constraints or handicaps can lower the cheatiness level of an Orion drive? Is the Orion drive presented in the above mod actually realistic?

- What effects does the usage of an Orion drive have on crew and fragile freight? Does the crew have to be placed in hibernation before using the Orion drive to prevent death?

- What effects on the environment does the Orion drive have? Should usage within the closer proximity of Kerbin be prohibited in order to prevent radioactive fallout?

- How to safely eliminate an expended or defective Orion drive? I think crashing it straight into Kerbin won't be very healthy for the Kerbal Space Program and the insurance agency.

- Should the Orion drive generally be used for longer burns or for course correction?

- Is the throttleability of an Orion drive legitimate and realistic? How would it be reached in real life (adjusting time between bomb detonations, using weaker bombs for fine-tuning, etc...)?

 

 

[Hannu2]

5 minutes ago, MedwedianPresident said:

What are YOUR opinions to the following questions:

- Is using the Orion drive considered "cheating"?

- Is it allowed in the late part of a career game or while playing with a high technology level / recreating Sci-Fi missions in sandbox?

- What constraints or handicaps can lower the cheatiness level of an Orion drive? Is the Orion drive presented in the above mod actually realistic?

- What effects does the usage of an Orion drive have on crew and fragile freight? Does the crew have to be placed in hibernation before using the Orion drive to prevent death?

- What effects on the environment does the Orion drive have? Should usage within the closer proximity of Kerbin be prohibited in order to prevent radioactive fallout?

- How to safely eliminate an expended or defective Orion drive? I think crashing it straight into Kerbin won't be very healthy for the Kerbal Space Program and the insurance agency.

- Should the Orion drive generally be used for longer burns or for course correction?

- Is the throttleability of an Orion drive legitimate and realistic? How would it be reached in real life (adjusting time between bomb detonations, using weaker bombs for fine-tuning, etc...)?

 

 

It is not cheating, if you do not take part to challenge or competition which does not enable it. I do not see any use for it in normal game. I can send whatever I want (or my computer can handle) to wherever I want. I use such roleplay that nuclear stuff is not allowed to hit Kerbin or be used in atmosphere, if it is not necessary for save the crew. I would count Orion as a nuclear stuff if I used it. Environmental effects must be tremendous because USA and USSR banned nuclear tests in atmosphere soon after they get them work reliably. Probably any intelligent creature capable of spaceflights would not allow such devices on their home planets. But there could be Orion spaceport on Minmus or orbit.

Probably Orion is not very accurate for small course corrections. But maybe 20 km/s is a small correction in interstellar traveling. There is not any physical restrictions to make one bomb correction. Orion can be throttled by making time between explosions longer or by using smaller bombs or bombs with less work mass around them. However there is practical limit how small fission bombs can be. But it should be easy to take Skipper and couple of orange tanks fuel for small adjustments.

[cantab]

It's no more or less "cheating" than anything else. By itself against the stock parts I think it will be grossly unbalanced though, at least outside career mode where cost can check it. But that's because nuclear pulse propulsion is exceptionally capable in real life. Nothing else offers the same combination of high thrust, high specific impulse, and high technology readiness.

As far as environmental impact goes, you arguably don't even want to be in your planet's magnetic field when you start using these things, so you need to get on a high trajectory first. On the other hand if you really don't give a flying fig about the environment, an Orion Drive can launch from within the atmosphere. And actually, for a small ship the nuclear fallout wouldn't be all that severe. You're looking at a total yield of maybe 25 kt, mostly detonated high in the air. Compared to the nuclear tests conducted in the Nevada desert, an Orion launch is no big deal.

Edited December 17, 2015 by cantab

[More Boosters]

28 minutes ago, Hannu2 said:

But maybe 20 km/s is a small correction in interstellar traveling.

Just a small nitpick, I think you meant m/s because 20 km/s is like, your orbital velocity in Moho's orbit. How is doubling that a small correction?

And 20 m/s can make or break an intercept.

[Waxing_Kibbous]

I have Roverdude's warp drive in my tech tree, and since it is integrated into the tree it takes something like 10,000 science to unlock so I don't consider it cheating If you are having fun and like a certain part that's your business!

[Kerbol Macrosystems]

...Scott Manley did make an Orion drive plane...

[Whizzkid]

9 minutes ago, Kerbol Macrosystems said:

...Scott Manley did make an Orion drive plane...

...Whackjob made an Orion drive sepatron...

[nosirrbro]

I would say its not quite cheating, but in order for it to make sense, it must be in an interstellar situation, and also should be accompanied with alot of other parts to make it balanced. Basically, its not cheating, but doesn't make sense without a heavily modded save.

[Hannu2]

7 hours ago, More Boosters said:

Just a small nitpick, I think you meant m/s because 20 km/s is like, your orbital velocity in Moho's orbit. How is doubling that a small correction?

And 20 m/s can make or break an intercept.

I do not know performance of that mod, but as far as I know real Orion have dv of hundreds of km/s. It has suggested to real interstellar traveling. It does not need small correction maneuvers on accurate Hohmann orbits. You just turn nose to the target and open full throttle. If it seems that you do not hit, you burn radially until you are on course. 20 km/s does not destroy your dv budget. Trajectories are slightly bending hyperbola around Sun. Gravity is just a small perturbation and not dominant factor.

Why you and so many other are so worried about cheating? This is single player's game and everybody makes their own rules, for example rolegame things. Someone ban nuclear devices totally, somebody think that kerbals can be years without food and are immune to cosmic radiation because their metabolism is based on nuclear reactions and somebody destroy KSC and kill kerbals by exploding modded nuclear bombs. Everybody are right, they all have fun. It is main objective of gaming. Everyone should try mods and rolegame rules and decide if they are too overpowered or restrictive in own gaming style. Many people like Orion and if you feel it may be interesting why you have to ask permissions from us. Mod is free to download and simply to install. Make a copy of your save and you can return back to this point if you do not like Orion mod.

[PanzerAce]

11 hours ago, MedwedianPresident said:

- Is using the Orion drive considered "cheating"?

- Is the throttleability of an Orion drive legitimate and realistic? How would it be reached in real life (adjusting time between bomb detonations, using weaker bombs for fine-tuning, etc...)?

 

 

These are the only two Q's you had that I really care about. And in order:

 - Yes, it is cheating. But only because It's cheating IN REAL LIFE. It's the closest humanity has to a torch ship (being defined as something with simply ludicrous amounts of delta v). You get both high thrust and (relative to what we have now) high Isp. We had the technical knowledge in the 50s and 60s to put essentially as much mass as we wanted into orbit around the earth (or slightly less unreasonable amounts of payload around mars, or saturn, or, you know, anywhere). For an excellent read on Orion (and, well, everything space), this is where to start: http://www.projectrho.com/public_html/rocket/

- Sort of. The easiest way to throttle an Orion plate would be with variable yield bombs. The problem though (as I understand it) is that to throttle, you essentially have to pick what acceleration you want, figure out what yield you'll need for that, let the plate come to a stop at the mid point, then launch a half-charge, then go to the full charges for your give acceleration.

[KerikBalm]

I don't think you would do much throttling with an orion drive.

Its not quite a "torch ship" under normal definitions... it would not constanty thrust... it would not fly brachistichrone trajectories.

It would fly very high impulse trajectories. It would operate at essentially full throttle (at essentially as many G's as the ship/crew/payload can handle) until its on the desired trajectory... then it would coast, and go full throttle to break at its destination again.

It wouldn't fly hohmans, but it wouldn't be under constant thrust like a "normal torchship".

It could be something like "detonate 561 bombs to put us on a trajectory to reach mars in X days". To go slower or faster, you just increase or decrease the number of bombs... essentially the "burn time". It would be more like a SRB that you could shut off (or many real life liquid fuel engines that don't really have much throttle control, just the ability to be shut off).

For times when 1 more bomb would be too much (a course correction.... but again, an orion ship could go so fast that this wouldn't be a problem... but of course, you could choose to go on slow hohmans to conserve bombs), you could use reduced yield bombs.

If that isn't enough, you could also alter the bomb timer to detonate farther away from the ship, so that more of the blast misses the ship - its a shaped charge, so the blast is focused in a cone, for maximum efficiency you would want the diameter of that cone to be the diameter of your pusher plate - but if you want precision, you can let the bomb explode father away so the cone expands more.

[ment18]

Orion mods are all OP compared to stock KSP parts.  The main issue in KSP is structural integrity of payloads.  Its easier to launch heavier payloads because they have worse t/w.

I don't think it would be very dangerous in real life, especially compared to other things (like driving).  Nuclear bombs won't detonate on their own.  Couldn't we build a large barge, sail to the middle of some ocean and then launch with much weakened bombs because the atmosphere increases the thrust of the rocket?

 

[wumpus]

What could make an Orion OP/cheating?

Blasting off Kerbin would wreck environmental havok.  The initial calculations of minimal loss of life failed to include the existence of the (later discovered) magnetosphere.  You need to be out around Mun to start it up.  Newton also strongly implies that if you have multiple duds on your liftoff and the thing comes crashing down (see Antares), it will come down with the force of N atomic bombs where N is the number of non-duds that lifted it up.

If you somehow drag/build the thing into Mun orbit, Bob's your uncle.  The whole thing can be basically built with 1950/60's technology (except the whole "be in munar orbit bit).  I'd certainly assume the whole pusher plate/ballast bit (the bombs explode off a plate that needs a mass similar to that of the rest of the ship) needs to be built out of an asteroid, and you will likely need a lot more shielding elsewhere that will come from asteroids or munar /[minmus] surfaces.

One "limit" that might be missing a KSP mod is that the thing wasn't expected to go much past .1C.  I don't know if this was a limitation of the rocket equation and the ISP of H-bombs or the issue of shielding while the ship is bombarded by .1C interstellar particles.  Just understand that it likely takes tech not discovered between 1960-2015 to go faster than .1C.

[Red Iron Crown]

4 minutes ago, wumpus said:

Blasting off Kerbin would wreck environmental havok.  The initial calculations of minimal loss of life failed to include the existence of the (later discovered) magnetosphere.  You need to be out around Mun to start it up.  Newton also strongly implies that if you have multiple duds on your liftoff and the thing comes crashing down (see Antares), it will come down with the force of N atomic bombs where N is the number of non-duds that lifted it up.

Over 2000 nuclear warheads have been detonated on Earth without too much environmental effect. The undetonated bombs are extremely unlikely to go off in the event of a crash, they're just not that easy to set off.

[Wallygator]

Players sculpt their craft using parts in many ways, and we sculpt our individual ksp implementations using mods. Unless squad implements a "cheat catcher" protocol and announces what actually is cheating, then the use of the word "cheating" is an empty concept. 

Its a sandbox game!

[peteletroll]

You can probably "throttle down" the Orion engine by increasing the distance the nuclear bombs explode at.

[wumpus]

4 hours ago, Red Iron Crown said:

Over 2000 nuclear warheads have been detonated on Earth without too much environmental effect. The undetonated bombs are extremely unlikely to go off in the event of a crash, they're just not that easy to set off.

The problem isn't the undentonated bombs going off (although anything that scatters plutonium* is nuclear proliferation issue).   It is more the entire energy invested in the Orion coming up crashing right down.  Ordinary rockets do have the threat of all the fuel exploding at once (oddly enough, while SRBs are feared due to their tendency to "explode", this isn't really a danger for them).  The difference is that an Orion will likely weigh as much as a battleship: the shear mass and velocity of all that coming down is the danger.  If it took n atomic bombs to get it up, it is coming down with the force of n atomic bombs.

Note the [fallout] analysis is from George Dyson's book "Project Orion: The True Story of the Atomic Spaceship".  I'd assume that it was being more than fair to his father's space ship.

* as far as I know, the Pu needed for a bomb and the Pu needed for a nuclear thermoelectric generator are two different isotopes.  The Orion obviously needs the scary ones.

[Red Iron Crown]

4 hours ago, wumpus said:

If it took n atomic bombs to get it up, it is coming down with the force of n atomic bombs.

Only a tiny fraction of the energy of each bomb is added to a nuclear pulse-driven ship. It would be less than 50% if the bomb was detonated adjacent to the pusher plate, and the fraction goes down with the inverse square of distance from the bomb if further away.

[PanzerAce]

2 hours ago, Red Iron Crown said:

Only a tiny fraction of the energy of each bomb is added to a nuclear pulse-driven ship. It would be less than 50% if the bomb was detonated adjacent to the pusher plate, and the fraction goes down with the inverse square of distance from the bomb if further away.

Not exactly. As mentioned previously, a requirement for a usable orion drive is a nuclear shaped charge, delivering far better than 50% of the yield as energy to the pusher plate, and fairly insensitive to distance in terms of energy delivered until it's past the optimum distance, where the cone from the shaped charge is larger than the plate itself.

[Red Iron Crown]

10 minutes ago, PanzerAce said:

Not exactly. As mentioned previously, a requirement for a usable orion drive is a nuclear shaped charge, delivering far better than 50% of the yield as energy to the pusher plate, and fairly insensitive to distance in terms of energy delivered until it's past the optimum distance, where the cone from the shaped charge is larger than the plate itself.

Newton would seem to imply that no more than 50% of the bomb's energy can be directed in that manner, it's an upper bound.

[MarvinKitFox]

3 hours ago, Red Iron Crown said:

Newton would seem to imply that no more than 50% of the bomb's energy can be directed in that manner, it's an upper bound.

Fortunately, these would be designed by someone that has a clue what he is doing, not you or Newton.

 

Newton's law does dictate that the *momentum* resulting from an explosion would have to be symmetrical , but there is no such limitation to the *energy* distribution.

[KerikBalm]

KE=1/2MV^2

If you want to have a high exhaust velocity (ie, Isp), then neccessarily, most of the energy is going into the exhaust.

Much like if you were to use a photon drive... you accelerate your craft at far less than 1 µm/second, which raises your KE very slowly... yet that laser/phon drive will be putting out gigagjoules of energy.

Most of the energy goes into the exhaust, because it leaves at a much higher relative speed than the main craft.

Furthermore, the rocket equation comes into play when you have a significant fraction of your craft being propellant.

If 90% of your craft's mass is bombs, then obviously, only 10% of the first bombs energy could actually go towars accelerating the ship, while the rest goes to accelerating the other bombs. When its out of bombs, it has only a tiny fraction of energy from the first bombs.

[Red Iron Crown]

3 hours ago, MarvinKitFox said:

Newton's law does dictate that the *momentum* resulting from an explosion would have to be symmetrical , but there is no such limitation to the *energy* distribution.

Gah, always mix up those two. Thanks for the correction.

[Hannu2]

19 hours ago, Red Iron Crown said:

Over 2000 nuclear warheads have been detonated on Earth without too much environmental effect. The undetonated bombs are extremely unlikely to go off in the event of a crash, they're just not that easy to set off.

Yes, it is extremely difficult to get nuclear bomb to explode. It needs nanosecond level timings and very special detonators and control electronics. However, there may be lot of other problems if thousands of nuclear bombs are spread out on large area. If Orion does not fall on deep ocean it is practically impossible to prevent that wrong people get bombs. That would give very neat possibilities to terrorists, criminal organizations, rogue governments and even insane individuals to find loads of more or less damaged nuclear bombs. Also some normal people could not resist their curiosity and they would make experiments or keep nuclear material stored.

[More Boosters]

On 18.12.2015 at 8:00 AM, Hannu2 said:

I do not know performance of that mod, but as far as I know real Orion have dv of hundreds of km/s. It has suggested to real interstellar traveling. It does not need small correction maneuvers on accurate Hohmann orbits. You just turn nose to the target and open full throttle. If it seems that you do not hit, you burn radially until you are on course. 20 km/s does not destroy your dv budget. Trajectories are slightly bending hyperbola around Sun. Gravity is just a small perturbation and not dominant factor.

Why you and so many other are so worried about cheating? This is single player's game and everybody makes their own rules, for example rolegame things. Someone ban nuclear devices totally, somebody think that kerbals can be years without food and are immune to cosmic radiation because their metabolism is based on nuclear reactions and somebody destroy KSC and kill kerbals by exploding modded nuclear bombs. Everybody are right, they all have fun. It is main objective of gaming. Everyone should try mods and rolegame rules and decide if they are too overpowered or restrictive in own gaming style. Many people like Orion and if you feel it may be interesting why you have to ask permissions from us. Mod is free to download and simply to install. Make a copy of your save and you can return back to this point if you do not like Orion mod.

WTF where did I mention cheating or anything?