In rope rescue scenarios, particularly those involving raising systems, managing a mid-line knot can be a critical challenge. Whether the knot results from extending rope length or bypassing damaged sections, failure to address it safely can bring operations to a halt. Fortunately, integrating a Prusik hitch into the system offers an efficient and controlled method for passing knots during a raise, keeping load tension intact and minimizing disruptions.
The Prusik hitch, when properly deployed, acts as a mid-line capture and holding mechanism, allowing rescuers to isolate and manage specific sections of the rope. When paired with mechanical advantage systems such as a 3:1 haul system and devices like the CMC Clutch, this technique enables a seamless transition while preserving both redundancy and load integrity—two essential elements under NFPA 1006 guidelines.
This blog explores not just the technical “how” of this knot pass method, but the “why” behind each component of the sequence, emphasizing real-world context, risk management, and rigging logic.
Initial System Setup: Establishing Control Before the Pass
The operation begins with a deliberate setup: raising the load until the knot and Prusik hitch sit roughly 1.5 meters below the primary descent device. This distance is not arbitrary—it ensures adequate working space for technicians to manipulate devices, tie or untie components, and apply tension without congesting the rigging area.
A Prusik hitch is reset on the alternate rope (assuming a twin-tension configuration or dual mainline scenario). This backup rope now becomes the designated load path during the knot transition. It is essential that this Prusik is pre-tensioned and fully functional before proceeding. Redundancy and fail-safe structure are paramount.
Load Isolation with a Temporary Anchor
With the primary rope scheduled for adjustment, the team must first isolate the load safely. The hauling Prusik and pulley are disconnected to prevent interference. In their place, a new Prusik hitch is placed below the knot on the working rope.
This hitch is anchored using a load release strap—a tool that provides both adjustability and controlled tension transfer. The temporary anchor functions as a load catch, holding the system steady while the primary line is manipulated.
The introduction of this anchor marks a strategic pivot: the system now has two points of load control—the standby Prusik on the alternate rope and the anchored Prusik on the primary rope.
Slack Management and System Rerigging
At this point, the hauling team applies force to the alternate rope. The goal is simple: introduce just enough slack into the rope containing the knot to permit safe rerigging.
Once this slack is confirmed, the rope is removed from the Clutch, rerouted, and rethreaded so that the knot now sits above the device. This detail is critical: positioning the knot below the device could obstruct the next stage of haul operations.
This rerig must be done cleanly—free of twists, misalignments, or cross-loading. Each component is checked for readiness before releasing the temporary anchor.
Transition to a Refined Raising System
Now that the knot has been cleared and the rope repositioned, it’s time to restore system flow. The temporary Prusik hitch and load release system are removed.
A 3:1 mechanical advantage system is re-established below the Clutch, connecting directly into the newly rerigged rope. This ensures that the lift can continue with the same directional logic and force distribution as before.
This new setup must be rebalanced. Technicians monitor pulley alignment, rope glide, and the rigging triangle. Only after full confirmation of load control does the team resume the raise.
Why This Technique Matters in Rescue Contexts
The Prusik-based knot pass is not just a workaround—it is a blueprint for critical thinking under pressure. By allowing rescuers to isolate, reposition, and reload rope segments while maintaining full control of the load, this method represents applied system intelligence.
- Safety First: The system never lacks a backup, even during transitions.
- Operational Fluidity: There is no need to lower, detach, or overcomplicate the system to bypass a knot.
- Gear Compatibility: This technique works across devices like the Clutch, MPD, or Petzl Maestro, offering universal value.
For teams working in vertical terrain, confined environments, or extended-haul scenarios, mastering this method transforms a potential failure point into a seamless continuation of movement.
Ultimately, passing a knot in a raising system with a Prusik hitch is more than a technique—it is a discipline of preparation, timing, and confidence. And when deployed with rigor, it becomes one of the most reliable tools in the modern rescuer’s playbook.
Peace on your Days
Lance
