ملف:A Chinook helicopter and a Royal Marine rigid-inflatable boat (RIB), off Studland Bay, Dorset, UK. MOD 45155975.jpg

A Royal Marine rigid inflatable boat dangles from a Chinook helicopter during a hazardous 'Underslinging', a method of quick extraction and insertion of waterborne personnel.

The daring procedure involves the helicopter lowering strops and coming down to just above sea level at which point the boat and crew will push through the down draft under the helicopter and attach the lines to the boat. The helicopter will then lift the boat with crew still in it clear of the water once clear and the boat is airborne, the crew will be individually winched up into the helicopter. On returning the boats crew fast-rope down into the boat ready once set the helicopter will deploy the boat and crew back into water.