RoverDude wants an Orion Drive?!

[pincushionman]

Whaaa....

Saw it on the KSP facebook - sorry, I'm not sure how to link that here yet - and thought "Is this what we really need?"

Any thoughts oh how it might work? Normal throttle control doesn't sound right. More like a RMB action to instantly apply an impulse?

[Whirligig Girl]

It's being made. It will use pulses of bombs, so the thrust controls how often the bomb pulses. At least, that's how the old Orion mod worked.

[ToyotaTim]

RoverDude isn't the first one to do this IIRC. Someone has made such a mod before. And Scott Manley has made a video about this propulsion method/mod on his youtube channel. probably 1-2 years ago..

EDIT: GregoxMun ninja'd me

[Red Iron Crown]

It's a mod part he promised if he reached a certain threshold of Patreon support. Doubt it will be in the stock game.

[Scotius]

Really? What is so enticing is Orion Drive that people obsessively keep dreaming about it? Slamming your own ship with dozens of nuclear explosions - what a brilliant idea. Really, what can go wrong with it?

[Red Iron Crown]

What is so enticing is Orion Drive that people obsessively keep dreaming about it?

It is tremendously efficient, propellant mass-wise. Isp starting at around 3400s and upwards from there, read more here.

[Red Dwarf]

I believe the way throttling works on an Orion drive relates to detonations-per-second. Really, each explosion provides the same amount of force on the craft, but it's only applied for a fraction of a second. You accelerate faster the more explosions you have in sequence.

Also, I doubt this is going to be a stock feature. Roverdude does still make mods, after all

Edit:

Also, here's the picture, for people who are curious:

[Kerbart]

The one propulsion that would even have Jeb scream in agony!

[Lord Aurelius]

The one propulsion that would even have Jeb scream in agony!

Agony?!? More like pure ecstasy. What's better than an extremely efficient propulsion system that uses large explosions to launch your rocket?

[sal_vager]

Looks like 'Ol Boom Boom', and RD has a thread on his Orion drive here.

[lordlundar]

It is tremendously efficient, propellant mass-wise. Isp starting at around 3400s and upwards from there, read more here.

Problem is that's the only thing it's efficient in. Most of the energy from the blast is wasted, you need materials that can withstand kinetic force in the range of several thousand PSI as well as superheating just to get any decent velocity, then there's the whole "irradiating half of a planet" issue.

Really when you think about it, all an Orion drive is is a supercharged pulse engine. Those aren't used wide scale for largely the same efficiency issues as well.

[Red Iron Crown]

It certainly faces some challenges, and I'd agree that using it on Earth is unlikely to be feasible. Among the futuristic high efficiency engines about the only benefit it has is that relatively little new technology needs to be developed to make it work.

It also has the virtue of fitting in well with the "kerbal" aesthetic.

[Tourist]

Moar boosters? No! Are we making toys for children now? MOAR NUKES!!! MWHAHAHAHAHAHHAHAHAHAHA!!!!!

[panzer1b]

If this is implemented i hope we can get shockwaves added from explosions in general. Right now you drop a 14400 tank beside a massive exposed rocket, and it doesnt do anything to it but desintegrates on contact with the ground.

As for the nuke engine, while i can see it being useful, im wondering how effective itll be as a weapon, mount 2 of them, one front one rear (to counter the thrust), and fly up to something then nuke it.

[sewerbird]

It'd be amusing if the mod was done such that, if used on the launchpad, it'd blow up just about all the KSC buildings.

[Nathair]

Really when you think about it, all an Orion drive is is a supercharged pulse engine. Those aren't used wide scale for largely the same efficiency issues as well.

I wouldn't say so. While it is true that Orion (or, better yet, Medusa) does have a "pulsed" thrust system there the resemblance ends. Pulse detonation problems as I understand it primarily concern cycle time design issues (which have no parallel in Orion) and vibration problems which Orion addresses directly (and Medusa does even better.)

[LitaAlto]

FWIW, TiktaalikDreaming adapted Nyrath's original Orion mod, so those who want to go BOOM today, can.

[regex]

The thing that makes the Orion drive so good is the high thrust power combined with a fairly decent isp. Unfortunately the place where this is the most useful is also the place where the Orion drive does the most damage. As far as in-space drives go, the Orion is fairly typical if you're not talking about military craft since the big concern is isp. It is outclassed by other, more advanced drives (plasma inertial confinement is a good one to look forward to.)

[NovaSilisko]

Problem is that's the only thing it's efficient in. Most of the energy from the blast is wasted, you need materials that can withstand kinetic force in the range of several thousand PSI as well as superheating just to get any decent velocity, then there's the whole "irradiating half of a planet" issue..

I suggest you read more about it before disparaging it. The pulse units were effectively nuclear shaped charge devices, and in fact redirected the majority of the explosive energy back at the pusher plate. "Irradiating half the planet" is more of a concern when we're talking about a small planet like Kerbin. The bombs were designed to be very "clean" - and, due to them detonating high in the atmosphere (most of them anyway), they don't really pick up any fallout, so radiation release is minimized (for, you know, a nuclear bomb). The exception being the first bombs detonated near ground level, though that could be helped by the addition of booster rockets to give it an initial kick.

Really, all the issues you mention were actually worked out in surprising detail. Just on paper, though. They did build small scale tests using conventional explosives, which actually worked, apart from sort of veering off course due to having no guidance (and a few missed charges).

That's all just engineering; solvable problems. On Earth, though, I don't think project orion will ever fly. The general aspect of a giant nuclear powered spaceship the size of an aircraft carrier loaded with hundreds of nukes flying over your backyard/country is not an encouraging one to most people.

Now, if we could refine fissionable material from asteroids and build the ship at a near-earth asteroid, though...

Edited September 28, 2015 by NovaSilisko

[magnemoe]

The thing that makes the Orion drive so good is the high thrust power combined with a fairly decent isp. Unfortunately the place where this is the most useful is also the place where the Orion drive does the most damage. As far as in-space drives go, the Orion is fairly typical if you're not talking about military craft since the big concern is isp. It is outclassed by other, more advanced drives (plasma inertial confinement is a good one to look forward to.)

Orion is designed to move ship sized cargoes interplanetary distances, if you are not moving hundreds of tons you don't need it.

no it has to low ISP to work as main drive on a starship but magnitudes closer than anything else we can make today.

It would be nice to move asteroids around.

Have used it in KSP, fun but kind of overkill, would be perfect in 1.1 as with 64 bit you could scale up things a lot without memory problems, more planets longer distances, larger payloads.

Bringing 500 ton to Jool is no issue at all.

[mikegarrison]

What is so enticing is Orion Drive that people obsessively keep dreaming about it?

Basically, it's impossible to have manned space travel to anywhere farther than Mars using chemical rockets. And even Mars is a real challenge. You need nuclear power.

But every nuclear power propulsion system known is very low thrust, so trips will take a long, long time. Too long to be practical. Except, that is, for nuclear pulse detonation. It is both very high efficiency and very high thrust. You can go a long ways, and you can get there very quickly. You don't have to take Hohmann-type transfer orbits. Instead you just point and shoot, thrusting hard and then braking hard. It's much quicker.

What's more, it actually works better the more massive your ship is. So it rewards huge ships with the capability to take a lot of people and equipment and stay for a long time. Every other known propulsion system squeezes payload mass as hard as possible, but Orion encourages bigger masses. It's actually easier to build an Orion drive if your payload is the size of an ocean liner than it is if your payload is the size of a bus.

[RoverDude]

FWIW, TiktaalikDreaming adapted Nyrath's original Orion mod, so those who want to go BOOM today, can.

Actually... it's available today (the link was posted earlier). And for clarity - this is a mod, not stock

(And new screenshots....)

Edited September 28, 2015 by RoverDude

[magnemoe]

Nice and as OP as I remember

yes, this is an pretty standard Orion burn, it used around 900 charges, yes payload was just 20 ton or something, I was also running at 30% trust as maximum.

Wonder how well the medusa would work as an asteroid tug?

[Boris_T_Roach]

I'm getting strange

I read the thread title as RoverDude wants an onion drive

Boris

still alive...just about

[eddiew]

yes, this is an pretty standard Orion burn, it used around 900 charges, yes payload was just 20 ton or something, I was also running at 30% trust as maximum.

Oh my stars... I need this in my life. Along with 64 bit and a ton of planet packs. How long did it take to accelerate to that speed? Feels like you'd be booming all the way to the edge of Kerbin's SoI

- - - Updated - - -

I read the thread title as RoverDude wants an onion drive

You aren't alone in that...