Ed Crooks BP oil spill report: Eight distinct failures led to the accident

Bly goes on to give the 30-second version of the report’s conclusions, which is that there were eight distinct failures that led to the accident, and it was only because all eight of those factors went wrong that the explosion and subsequent leak occurred.

“At the end of the day, all eight of these things had to occur to get from the initiation of this to the end of the accident,” he says.

One member of the accident investigation team worked on the inquiries into the Challenger and Columbia space shuttle disasters, which is highly relevant experience for understanding the failures of complex engineering procedures in the difficult and dangerous conditions in a mile of water and a further 2 ½ miles of rock below the sea bed.

Bly explains a few problems the investigation has faced, working to deliver its report in the 4 ½ months since the disaster. His team has not been able to interview all of the potentially important witnesses, and the blow-out preventer, the stack of valves on the sea-bed that was intended to stop oil and gas escaping but failed in the accident, has only just been raised to the surface, and has not yet been fully examined.

One of the problems he does not mention, which is explained in the report, is that the team was not able to analyse samples of the cement used to seal the well, because Halliburton, the cementing contractor, has refused to supply BP with samples, and taken legal action to enforce that refusal.