KerbalX

Description

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.

Built in the VAB in KSP version 1.0.4.

Details

• Type: VAB
• Class: lifter
• Part Count: 217

• Stock: yes

• Crew: 1 engineer

• Cost: √663,131

• Reusable: yes

• Docking: 4x Sr., Klaw

• Delta-V: 4500

Procedures

Launch:

The launch stages are combined - this thing is heavy, and needs to arrive into orbit with a lot of fuel left, plus the shape is rather unwieldy. Luckily, once in orbit, it should serve you for a long time.

• Start the turbojets and allow them time to spin up.
• Enable SAS and RCS, leave at Stability Assist.
• Launch.
• Wait until speed climbs to at least 50m/s, then begin gravity turn by tilting by 10 degrees right (heading 90). Yes, it’s late, it’s steep and inefficient, but this is not your average rocket. Flatter trajectories end with a disaster or at least in damaged gigantors.
• When the prograde marker catches up with heading, set SAS to Prograde. (it has a tendency to drift and flip if allowed to wander too far from prograde).
• Stage the SRBs, first pair of Mammoths and the turbojets when each burns out.
• Once the second pair of Mammoths sputters out, your apoapsis should be already above the atmosphere. Cut the engines, stage the mammoths, then burn very gently for a second or two to begin clearing them.
• Go to map and prepare a circularization node at the apoapsis. It will be about 1100m/s of delta-V.
• Set Node in SAS, then decouple all four hats on the docking ports on top of the ISRUs. (rightclick, decouple node).
• As the craft finishes turning into the maneuver, the hats should be cleared and the time to burn should be about right.
• Perform the circularization burn
• Press 0 to unfold the gigantors

Docking to asteroid for capture:

• After rendezvous, switch HUD to Target.
• Set Klaw to Control from Here.
• Set SAS to prograde. (note Klaw is facing back, so you’re in fact heading retrograde)
• Rightclick Asteroid and pick Target center of mass
• Using RCS Translate move relative to the asteroid until the target is in the middle of navball (keep Target marker between center marker and Prograde marker to get it right).
• When Target, Prograde and navball center are lined up, translate forward towards the asteroid, and arm the Klaw.
• Slow down to below 0.2m/s before contact.
• Due to the nature of the tug, the aim doesn’t need to be perfect, but it can help reduce wobble problems.

Braking cycle

• Switch the ISRUs off! - without that you’ll be getting some pathetic thrust of order of 80kN; it’s a KSP bug.
• Switch Stability Assist on. Not any others. If you need to correct your course, you’ll do it separately. During a full thrust burn in any other mode SAS loves to start turning the tug around until something snaps. (you can leave SAS off, but you’ll drift worse than in Stability Assist).
• Press and hold Shift. Don’t start with Z, the jerk of these engines can really break something if you don’t ease into full power.
• Don’t enable Phys-warp, or at least not above 2x. Wait for the burn to complete. You may gently adjust the course, though if it goes awry, just cut the engine and bring it back gently, don’t fight. Best not to touch the direction during the full burn.
• As you’re about to run out of fuel, ease the throttle to 1/3 before letting it sputter out.
• Enable the ISRUs and the drills. You may choose to enable only one drill, it should still overtake the ISRUs, and it’s longer until it fills up the ore containers. Set time warp of about 1000x.
• When ore is full, stop the drills. (this is to avoid KSP bug that makes drills deplete the asteroid at full speed regardless of actual ore production). Re-enable them when ore is depleted.
• Repeat until refueled. You may rotate the asteroid in the meantime.

Turning with the asteroid

• Don’t try the RCS alone. It’s far too weak.
• Either set throttle to some 10%, or just enable the ISRUs and set throttle to full.
• Begin turning in the desired direction (you may use SAS).
• Once the heading is right, stop the rotation by setting warp 5x.

If you have wobble problems after exiting warp

• they can escalate badly and break everything. It’s a bug that is closely related to the Kraken, resulting from the Klaw use.
• Switch to KSC or a different craft
• If the game forbids you (ship is under acceleration) keep trying, there’s a short window every few seconds when it’s possible.
• After you switch back, the wobble should be either gone or much weaker. Repeat if necessary.
• If the problems don’t want to go, save, quit KSP and restart it.

Remember: Like every asteroid tug, Claymore uses the Klaw, which is a Kraken bait. Save often, backup your saves and restart KSP if you see weird things going on. Don’t give the Kraken a chance to strike.

Untested: If you want to recover/land the Claymore, you can try docking extra pieces with a bunch of parachutes to it. Do it asymmetrically, leaving most of parachutes on one side, and it should land okay, not losing the parachutes when standing on the blade.

Action groups

6 - Stop drills

7 -Start drills

8 - Stop ISRUs

9 - Start ISRUs

0 - Toggle gigantors

Hey, 100 downloads and still only one upvote… c'mon, if I managed to help you get that Class E into orbit, come back and give me a thumb up. please?