Plastic bubbles help refloat capsized ship

Freighter comes right-side-up along its Persian Gulf dock, as was planned. Mud marks on superstructure indicate stages of bubble pumping. Refloating job required 150 tons of foam
When a freighter carrying 5,000 sheep capsized at the docks in Kuwait harbor in the Persian Gulf and threatened to contaminate a water-purification plant, an idea from a Walt Disney Donald Duck cartoon helped to raise it. Karl Kroeyer, a Danish engineer called in, remembered the cartoon in a Copenhagen newspaper.
Plastic-foam bubbles are shown at connection where one hose was uncoupled for inspection.
In it Donald pumped tennis-balls into the hold of a sunken ship to displace the water and give the ship enough buoyancy to float. Instead of tennis-balls, Kroeyer used polystyrene foam. The plastic is in crystals that heating expands to air-filled bubbles occupying 40 times the volume.
The freighter’s keel was weighted and the bubbles pumped first between the two highest decks, then into lower holds. It took 150 tons of foam and three months to raise the ship and tow it savely away.
Capsized freighter lies on her side at dock in Kuwait. Sacks of polystyrene are at upper left.
Sandbags are placed on wire fencing attached at keel to counterbalance weight of superstructure.

Text source: Popular Science, aprile 1965, via A guidebook the the Carl Barks Universe
Image source: extracted from the Popular Science archive