Vertical Launch of a Grappling Hook

Abstract

Problems involving chains, cables, or ropes that are dropped, folded, or pass around pulleys attract ongoing interest, in part because they can become variable-mass situations if the chain is partitioned into sections for analysis. Less attention has been paid to trying to intentionally project the end of a string as far as possible. Here we consider the launch of a grappling hook connected to a long flexible rope, such as the cartoon character Batman might do. As a real-life example of their use, rocket-propelled ropes with grapnels were employed to ascend French cliffs on D-Day, although the wetness of the lines made the task more difficult than expected. Line launchers have also been used to access the roofs of burning buildings.