( CNN ) -- On June 11 , 1962 , three Alcatraz inmates -- John Anglin , Clarence Anglin and Frank Morris -- attempted to leave the infamous San Francisco Bay island prison in a bold escape attempt involving dummy heads , chipped-through walls and a raft made of raincoats . They were never seen again . For years , Alcatraz aficionados -- not to mention the authorities -- have wondered whether the trio could have survived the attempt and made it to freedom . Now a Dutch study has shown that , if their timing was right , the inmates just might have done so . Based on models of tidal currents in the bay -- and inspired by an episode of the Discovery Channel 's `` MythBusters '' -- the team of researchers showed that if the Anglin brothers and Morris left Alcatraz at midnight and headed north , they could have reached land . `` If they hit it exactly at midnight , the beautiful thing is that we see that they would have been sucked out towards the Golden Gate Bridge , '' Rolf Hut , one of the researchers , told the BBC , which first reported on the study . `` But the moment they were close to the Golden Gate would have been the moment the tide reverses . And that would give them a moment of slack tide , in which they could have reached marine headlands in the northern site of the Golden Gate Bridge , '' he said . The researchers put together a graphic for the best-case scenario : . The window , however , was narrow , Hut observed . If the three left before midnight , the tides would have pushed them toward the ocean , where they would have died of hypothermia , Hut said . And if they left after 1 a.m. , the tides would have pushed them toward the East Bay , and they also would have probably died of hypothermia in the cold waters . Hut allows that they could have survived the latter departure , though they were likely to have been picked up by police since they would have made landfall after sunrise . That 's the worst-case scenario : . Only one person , John Paul Scott , is known to have survived an Alcatraz escape attempt , and he was captured the next day . However , Scott 's successful swim across the channel to San Francisco -- six months after the attempt by the Anglins and Morris -- made it feasible that others could have done so as well . It 's unlikely , though possible , that the Anglin brothers and Morris are alive today if they survived . Clarence and John Anglin , who were bank robbers , would be 83 and 84 , respectively . Morris , who had an extensive record , would be 88 . Still , the case has remained open . At the time of a 2009 NPR report , the U.S . Marshals Service was still investigating the case , and though the FBI ended its investigation in 1979 , a note on an archived FBI web page devoted to the case says that any leads can still be called in . Alcatraz Federal Penitentiary was closed on March 21 , 1963 . It 's now a National Historic Landmark and is open to visitors .
Trio of Alcatraz escapees may have survived their journey , study says . Two brothers and colleague left in June 1962 and were never seen again . It 's likely they perished , but if their timing was right they could have made it , study says . One person is known to have escaped from Alcatraz while it was a federal pen .