Recovery of hydrofoils sinking to seabed of 200m in depth using simple holding device with chain net

A holding device with a chain net without a power unit was developed for automation and labor reduction in lifting heavy objects. The device has been successfully applied to the removal of wave-dissipating blocks. For the other use, it was applied to the recovery of hydrofoils from the seabed. This paper presents the outline of the device, model experiment for deep waters, and two cases of recovery of hydrofoils which sank to seabed of 200m in depth. From these results, it was proved that the device was effective also in recovery of the falling object in deep sea.