60 years before Titan implosion, loss of 129 aboard US Navy sub changed safety standards

The implosion of OceanGate’s Titan submersible last week, which killed the five people on board, has put the safety of ocean exploration in the spotlight — as did another Northern Atlantic underwater tragedy 60 years ago. In April 1963, the U.S. Navy nuclear submarine USS Thresher imploded off the c...