“Alright, what we’re building here is a 4:1 mechanical advantage system—simple, clean, and efficient. We’re using two double pulleys and a prusik to get the job done.

We’ll start with our anchor. This could be a bombproof point—say, a rigging plate attached to an artificial high directional or a tree if we’re in the field. At this anchor, we attach our first double pulley. This will be the fixed pulley in the system. Lock it in place with a carabiner. Make sure everything’s clean and in-line because any twist will increase friction and reduce efficiency.

Now, grab your haul line. Feed one end of that rope through the first sheave of the upper pulley—that’s the one at the anchor. From there, run the rope down to the load.

At the load, you’re going to clip in your second double pulley. That pulley is going to ride with the load—it’s mobile. Now feed the rope through both sheaves on this pulley. So it goes into one side, wraps around, then through the second sheave. Make sure your rope runs smooth and without twist as it exits.

Once you’ve passed through the lower pulley, route that rope back up to the anchor and pass it through the second sheave of the upper pulley. This is the last directional change before your haul tail exits the system.

At this point, you’ve routed the rope through four sheaves—two at the anchor and two at the load—which gives us a 4:1 mechanical advantage, theoretically speaking.

Now, before we haul, we need a progress capture. We’re going to install a prusik hitch on the rope right after it exits the system—so that’s on the haul tail, just past that upper pulley. Tie a clean 3-wrap prusik using 6 or 7 mm cord, and clip it back to your anchor or a secondary backup. This way, as you haul, that prusik locks the system if you let go of the rope. You’re not going to lose any ground.

And that’s your system.

This setup gives you the power of a 4:1 haul—enough to raise a load smoothly with a two- or three-person team—and the prusik gives you control. It’s fast to build, easy to reset, and provides a reliable baseline for more advanced mirrored or twin-tensioned systems if needed.”

Objective:

Create a 4:1 haul system that multiplies your input force by four, using a pair of double pulleys and a progress capture (prusik) for controlled lifting.

Gear Needed:

• 2 double pulleys (ideally with swivel side plates)

• 1 length of haul rope

• 1 load carabiner

• 1 anchor (e.g., bombproof anchor or tripod)

• 1 prusik cord (6 mm or 7 mm)

• Carabiners (locking preferred)

Step-by-Step Setup:

1. Anchor the Upper Pulley (Fixed Pulley)

• Attach one double pulley to your main anchor point using a locking carabiner.

• This pulley is stationary and will redirect the rope back down into the system.

2. Rig the Haul Rope

• Take the haul rope and feed it through one sheave of the anchored double pulley. This will be the starting point of your system.

• Run the rope down toward the load.

3. Attach the Lower Pulley to the Load

• Secure the second double pulley to the load (or a load carabiner/litter bridle).

• Feed the rope through both sheaves of the lower double pulley.

  • The rope enters the first sheave, loops around, exits, and then goes into the second sheave.

4. Return Rope to the Upper Pulley

• After passing through both sheaves on the lower pulley, route the rope back up to the second sheave of the upper (anchored) double pulley.

• Pass it through that second sheave and exit the system—this is your haul tail.

✅ At this point, the rope has passed through four sheaves total—two on the lower, two on the upper—creating a 4:1 mechanical advantage.

5. Install a Prusik for Progress Capture

• On the rope section coming out of the second sheave of the upper pulley (the haul tail), install a prusik hitch.

• Attach the prusik to the anchor or a separate backup line using a carabiner.

• This acts as a progress capture device (PCD), preventing the system from slipping back when tension is released from the haul line.

Alternative: Use a mechanical progress capture device (like a Petzl ID or TAZ LOV2) if friction hitches are not preferred.

6. Haul and Monitor

• Begin hauling by pulling on the haul tail.

• The system will provide a theoretical 4:1 MA (minus friction losses).

• The prusik locks the progress, allowing you to reset without losing ground.

• Monitor all pulleys and anchor points for load distribution and rope alignment.

Peace on your Days

Lance