A drill pipe got trapped and buckled in the device [blowout preventer or BOP] that was supposed to stop BP's Macondo well from blowing out last year, preventing key mechanisms from closing as they were designed to, according to a report...Determining the BOP's role…could be a major factor in how blame is split among BP and its contractors...The problem at Macondo appears to be that the pressure of the blowout knocked the pipe off kilter before the BOP ever had a chance to work...Transocean said the report exonerates the company and shows that the blowout preventer would have worked if it had been designed to keep the drill pipe in the right place during an explosion...The BOP was designed and constructed by Cameron International...[which] said...that the Deepwater Horizon BOP "was designed and tested to industry standards and customer specifications..." The report doesn't actually exonerate or place blame...Transocean employed many of the key crew members...[none of whom] tried to activate the BOP…until after natural gas and oil began spewing onto the rig deck... Transocean…[has stated that] readings masked what was happening in the underground well, which kept the workers from fully understanding how imminent a blowout was...[I]nvestigators found that…cables that would have transmitted the disconnect sequence to the BOP were most likely destroyed in the first explosion. The obliteration of those cables also may have prevented an automatic "deadman" function from [operating properly]…