In which position must the belayer be for a bottom belay?

For a bottom belay, the belayer must be positioned below the rappeler. This positioning is crucial because it allows the belayer to effectively manage the rope during the rappel, ensuring the safety of the rappeler. By being below, the belayer can immediately apply tension to the rope and arrest a fall if necessary. Additionally, this position helps to maintain a clear line for the rope and allows the belayer to provide feedback or assistance to the rappeler more effectively.

Proper positioning is essential for optimal performance and safety in rescue scenarios, as it provides the needed control to support the rappeler throughout their descent. If the belayer were to be above or at the same level as the rappeler, there would be an increased risk of becoming entangled in the rope or failing to catch a fall effectively, making the bottom belay function less reliable.