The authors of the report from the Norwegian company Det Norske Veritas are to appear before the Marine Board of Investigation Monday in Metairie, La., along with representatives of rig owner Transocean and Cameron International, maker of the blowout preventer, The (New Orleans) Times-Picayune reported Sunday.
Investigations of last year's BP disaster found a weak battery, a hydraulic leak, mismatched plumbing and faulty wiring in the preventer -- a four-story stack of valves, seals and slicing blades that was supposed to shut the well in an emergency.
Failure to maintain the equipment and to respond fast enough to the undersea leak was blamed.
But the Norwegian report indicates that the preventer might not have been up to the job in any case.
Within days of the April 20 explosion that killed 11, remote-controlled submarines were able to reactivate some of the preventer's functions, but the disaster only worsened.
Transocean concluded that conditions "exceeded the ... design parameters."
Engineer Bob Bea, a risk management expert, said preventers on most deep-water rigs are a decade old.