Engineer who developed a deep water submersible and used it to study the deepest part of the ocean, the Mariana Trench.
He studied economics, but the lure of explorations conducted by his father proved too great, and he quit school.
On the Challenger Deep mission, Piccard and a Navy lieutenant descended to a depth of more than 35,000 feet before finding the ocean floor.
He came from a family of noted engineers and explorers.
His father, Auguste Piccard, also built vehicles to go up high into the atmosphere and deep into the oceans.