How many persons are required to pull for a 2:1 system when tensioning highlines?

In a 2:1 mechanical advantage system for tensioning highlines, the number of personnel required to effectively pull the system often depends on the total load that needs to be moved, as well as safety and operational effectiveness.

In a 2:1 system, for every unit of force applied by the pulling team, the system effectively doubles that force at the load end. However, it’s essential to account for factors such as friction in the system and the actual load being lifted or tensioned. For instance, if the total load being managed requires more effort—due to friction or the weight of the load itself—more personnel may be needed to safely and efficiently operate the system.

The choice of nine persons allows for adequate strength to manage the forces involved while also factoring in potential fatigue or issues that may arise during the exercise. This extra safety margin is essential in technical rescue operations to ensure that the team can operate effectively and manage any unforeseen challenges, such as mechanical failures or the need to quickly adjust the system.

Thus, requiring nine persons for a 2:1 system provides a balance of power, safety, and operational effectiveness, which is crucial in rescue scenarios.