Claymore - Class E Asteroid Wrangler

[Sharpy]

[h=3]Description[/h] Claymore - High thrust Class-E asteroid wrangler. Stock craft of 100 parts (after dropping launch stages provided).

4000kN of two Rhino engines on an extended arm allow it to haul the largest asteroids with over 1m/s of acceleration without burning the asteroid and without causing instabilities of pusher crafts. Five ISRU units and an array of gigantors provide rapid production of fuel right off the asteroid pulled, with about 200m/s of delta-V applied to the asteroid per burn-refuel cycle every game hour (and less than five minutes real time).

It arrives into orbit with over 3000m/s of delta-V, ready to tackle any incoming asteroids. Fully fueled, it carries 4500m/s of delta-V to tackle the next target (or almost 5000 with ore tanks full). Swivels of the engines allow rotation of the asteroid without need to undock and redock in case of direction change.

KerbalX page

Download link

See the KerbalX page for operating instructions.

[pTrevTrevs]

It does look very much like a Claymore:

How the hell does it even reach orbit? I'd like to see a full mission album for this monster!

[panzer1b]

if it isnt fully fueled, i can see this EASILY getting to orbit, its like a super heavy capital ship that doesnt even have the annoyance of wings on it to screw up aerodynamics and make the lifter flippy. You might even be able to get most of this inside a fairing even.

[Sharpy]

if it isnt fully fueled, i can see this EASILY getting to orbit, its like a super heavy capital ship that doesnt even have the annoyance of wings on it to screw up aerodynamics and make the lifter flippy. You might even be able to get most of this inside a fairing even.

It starts fully fueled but arrives above the atmosphere some 1100m/s short of orbit, which it must produce out of own tanks.

The launch stage's core is four Mammoth-based boosters set up in Asparagus configuration, with Claymore's two Rhinos being the central stage. (there's also a cluster of SRBs to give the initial kick since the TWR with the mammoths is quite poor, and two extra boosters based on turbojets, simply exploiting the fact everything else is capped with shock cones.)

The ascent path is steep; a late, shallow gravity turn. It really seems like it can't fly in the atmosphere 20 degrees above the horizon. It's either 40 or -30. Start the gravity turn at 40m/s instead of 50 and you're ending up burning downwards. Anyway, the four booster stages (SRBs, first Mammoth pair, turbojets, second Mammoth pair) are just enough to set the apoapsis to some 80km at about 1200m/s of horizontal speed. The remainder is for the Rhinos.

Sure it would be much, much easier if I brought only enough fuel to make it to the orbit, and then refuel there. Except this is a chicken-and-egg problem: this is a craft for people who don't have an orbital refueling station, and its purpose is to let them build one! So, for that purpose, it arrives into orbit with quite enough fuel to bootstrap the operation by intercepting the first asteroid.

[Rune]

Cool an all, but just the opposite way of how I'm going about it:

The parts can fit into a SSTO bay, and it can run the single nuke constantly a 2/3rds thrust while producing a bit excess ore. I'd guess I'll be pushing the suckers ion-style. It's what I built when I realized this one was grossly overdone:

Rune. Since it's so light in parts and pushes so gently, I'll be able to run the clock fast instead.

Edited August 16, 2015 by Rune

[Sharpy]

A single nuke? Man, you've got a lot of time on your hands. BTW, that excess ore - depending on how much excess, that may be a problem if you capture asteroids for fuel. The drills keep draining the asteroid at full speed even if ore is used at 1% the speed it's produced. (still, this looks unkerbed, so without an engineer they may actually remain slow enough not to cause problems.)

Anyway, let me know how it goes when you get that Class E into LKO!

[Rune]

A single nuke? Man, you've got a lot of time on your hands. BTW, that excess ore - depending on how much excess, that may be a problem if you capture asteroids for fuel. The drills keep draining the asteroid at full speed even if ore is used at 1% the speed it's produced. (still, this looks unkerbed, so without an engineer they may actually remain slow enough not to cause problems.)

Anyway, let me know how it goes when you get that Class E into LKO!

Tiny bit, right now it goes into the small tank, but I could always turn one drill on and off to save some propellant mass. Then again, the nuke implies I am already more than twice as mass-efficient as your design just on account of isp (never mind empty weight!), so I could just chuck it as inefficiencies. Regarding the engineer, tough... I was seeing 1ore/s on the drills without one, and assumed the engineer multiplier only applied when mining on the ground.

Assuming a 1000mT E-class, I'm looking at 40kN/1000mT=0.04m/s^2. Meaning a 100m/s orbit correction/circularization after aerobraking is on the order of 2500s, or 41 minutes and some change. At x4 timewarp, that's ten minutes of gameplay, and I can be web browsing at that. Obviously, solar orbit rendezvous and a rather firm aerobrake is required if you don't want to grow old doing a brute-force capture on your way out of the kerbin system.

Rune. You know? You made me run numbers, and now it doesn't even look as bad as I feared. Thanks!

[Sharpy]

Maybe you won't grow old but you'll surely get white hair trying to aerobrake the asteroid. They overheat nowadays rather easily and are considered rather aerodynamic by the game physics. I ran aerobraking at 49km periapsis, entry at some 3000m/s, the asteroid heat bar got into dirty green/almost orange, and it lost a whooping 1.3m/s. After deploying 60 airbrakes that number went up to 2m/s.

The one I landed had 120 airbrakes on it and still just tore them off when drag became too high (but they managed to slow it down enough that it survived the reentry).

Of course you could go with Class C or smaller, and then the numbers will be much nicer.