CBS 60 Minutes - Blowout: The Deepwater Horizon Disaster

Deepwater Horizon's Blowout, Part 1: 60 Minutes' Scott Pelley speaks to BP's Chief Electronics Technician Mike Williams, one of the survivors of the deadly Deepwater Horizon oil rig blast who was in a position to know what caused the disaster. Williams was in charge of the rig's computers and electrical systems.

[Williams] says the destruction of the Deepwater Horizon had been building for weeks in a series of mishaps. The night of the disaster, he was in his workshop when he heard the rig's engines suddenly run wild. That was the moment that explosive gas was shooting across the decks, being sucked into the engines that powered the rig's generators.

"I hear the engines revving. The lights are glowing. I'm hearing the alarms. I mean, they're at a constant state now. It's just, 'Beep, beep, beep, beep, beep.' It doesn't stop. But even that's starting to get drowned out by the sound of the engine increasing in speed. And my lights get so incredibly bright that they physically explode. I'm pushing my way back from the desk when my computer monitor exploded," Williams told Pelley.

Part1
Part 2 follows...

Deepwater Horizon's Blowout, Part 2: Scott Pelley investigates the Deepwater Horizon oil rig explosion that killed 11, causing the ongoing oil leak in the waters off of Louisiana. Chief Electronics Technician Mike Williams talks about his harrowing escape and what happened after he got off the burning rig.

Pelley also talked with Dr. Bob Bea, professor of engineering at the University of California, Berkeley.

Williams' survival may be critical to the investigation. We took his story to Dr. Bob Bea, a professor of engineering at the University of California, Berkeley.

Last week, the White House asked Bea to help analyze the Deepwater Horizon accident. Bea investigated the Columbia Space Shuttle disaster for NASA and the Hurricane Katrina disaster for the National Science Foundation. Bea's voice never completely recovered from the weeks he spent in the flood in New Orleans. But as the White House found, he's among the nation's best, having investigated more than 20 offshore rig disasters.

"Mr. Williams comes forward with these very detailed elements from his viewpoint on a rig. That's a brave and intelligent man," Bea told Pelley.

"What he's saying is very important to this investigation, you believe?" Pelley asked.

"It is," the professor replied.

What strikes Bea is Williams' description of the blowout preventer. Williams says in a drilling accident four weeks before the explosion, the critical rubber gasket, called an "annular," was damaged and pieces of it started coming out of the well.

"According to Williams, when parts of the annular start coming up on the deck someone from Transocean says, ‘Look, don't worry about it.' What does that tell you?" Pelley asked.

"Houston we have a problem," Bea replied.

Here's why that's so important: the annular is used to seal the well for pressure tests. And those tests determine whether dangerous gas is seeping in.

"So if the annular is damaged, if I understand you correctly, you can't do the pressure tests in a reliable way?" Pelley asked.

"That's correct. You may get pressure test recordings, but because you're leaking pressure, they are not reliable," Bea explained.

Part 2
CBS 60 Minutes full transcript is here.