Bathyscaphe Trieste
On 23 January 1960, she reached the ocean floor in the Challenger Deep (the deepest southern part of the Mariana Trench), carrying Jacques Piccard and Don Walsh. This was the first time a vessel, manned or unmanned, had reached the deepest known point of the Earth's oceans. The onboard systems indicated a depth of , although this was revised later to ; fairly recently, more accurate measurements have found Challenger Deep to be between and deep.
David Apperley
David Apperley is an Australian technical diver and cave explorer. Apperley holds instructor levels in cave diving, Deep Mixed Gas Diving and Deep Closed Circuit Rebreather Diving and was the expedition co-ordinator for the Pearse Resurgence Project 1996-2003. 
He was the project leader on the Royal Mail Ship Niagara 2003 Survey Project, which involved the organization and planning of putting some of the worlds most experienced divers onto the 130 metre deep Niagara wreck site, off the North Island of New Zealand.