NEW ORLEANS — It had been a lucky ship, a charmed vessel among the 130 or so rigs that poke straws into the mud, rock and sand beneath the Gulf of Mexico to suck out its crude.
Its job had been to prowl for oil, and the Deepwater Horizon was a celebrated prowler. Last year, the rig punched into a field estimated at 3 billion barrels, one of the biggest discoveries ever in the high-stakes Gulf oil safari.
But at 9:53 p.m. April 20, the Deepwater Horizon's luck played out. A shrill blast of escaping gas and a geyser of black goo hurled high over the placid Gulf heralded its demise, and in minutes the $560 million giant vanished into a fireball that was visible far over the horizon.
In contrast to its swashbuckling past, the Deepwater Horizon's last day was one of frustration, cascading problems and, ultimately, calamity.
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By 1 a.m. on April 20, workers had finished injecting cement into the 4-mile-deep well they'd drilled to strengthen the sides and protect the pipe. It needed time to set, and then they'd test it.
During the previous weeks, the well had been troublesome. Pressure from the reservoir of oil and natural gas 18,000 feet beneath the Gulf floor was kicking at the pipe, and the Deepwater Horizon had been venting with loud huffs.
Commissioned in 2001, the Deepwater Horizon was in the vanguard of new drilling ships that are able to burrow deeper than ever before.
Its 2009 oil find, in a fist of ancient rock laid down in the epoch of dinosaurs and called the Lower Tertiary Trend, required it to drill 31,000 feet, one of the deepest wells in the world, deeper than Mount Everest is tall.
With such reach, it opened new exploration vistas for BP, which paid $20,312 an hour to lease it from its Swiss owner, Transocean Ltd.
After celebrating and cashing their bonuses from their big find, the Deepwater Horizon's crew learned that the rig was getting a new assignment.
Its prospecting days were over, and the Deepwater Horizon was to become a production platform, squatting semi-permanently over an oil dome 50 miles off the coast of Louisiana. BP hadn't announced the find, but it was thought to be huge.
At 8:20 a.m. on April 20, the workboat Damon B. Bankston arrived at the Deepwater Horizon, which it had been tending for two years. Its mission this day was to take drilling mud from the rig for recycling.
Crewmen attached a hose to the Bankston, and at 1:17 p.m., slurry began flowing between the vessels. At 5:17 p.m., it stopped, and the Bankston was told to stand by for more.
At least three times during the day, the crewmen aboard the Bankston were startled by sudden loud noises as bursts of pressure were released from the rig.
At about 5 p.m., the pressure tests were done on the newly cemented well. Something was wrong.
First, a test signaled that gas might have been leaking into the well. Another test found a "disturbing pressure imbalance."
Gordon Jones, 28, was a mud man on the Deepwater Horizon. A graduate of Louisiana State University, he was one of two specialists from M-I Swaco aboard the rig to advise BP about "mud."
Despite its indecorous name, drilling mud is a complex concoction of clay, minerals and other additives that keeps the drill lubricated and carries shavings back up to the rig. Its recipe depends on what kinds of surfaces the drill bit is chewing; one blend even uses diesel oil.
It's pricey, too. A bore such as the one the Deepwater Horizon had drilled would run up a mud bill of $10 million or more.
Mud is also the main line of defense against blowouts. It plugs the pipe and resists the massive pressure of gas and oil.
Though he wasn't scheduled to start his 12-hour shift until midnight, Jones went to the mud room about 9 p.m., told his M-I Swaco counterpart that he looked tired and offered to take over. His offer was accepted gratefully.
Jones, who'd been working aboard the Deepwater Horizon for two years, was on the third day of a weeklong shift. He'd be off for the next seven weeks.
His wife, Michelle, was eight months pregnant with their second child. He'd arranged time off to be with the baby.
This wasn't going to be a demanding rotation. With the well in its final stages of preparation, there was little need for new mud.
"Gordon said he was going out there to sit on his butt," recalled his father, Keith Jones, a Baton Rouge lawyer, who said he never worried much about the dangers aboard the rig.
"Honestly, what we worried about," he said, "was the ride in the helicopter."
It was a clear, calm night, and the smooth, black Gulf glowed with jellyfish. The visibility was 10 miles, and a first-quarter moon was setting.
Despite the pressure problems in the well, engineers decided at about 8 p.m. to resume extracting mud. At 9 p.m., the Bankston was told to stand by for more.
As the operation got under way, the pressure in part of the well spiked to 3,500 pounds per square inch, seven times what it had been before.
Capt. Alwin Landry of the Bankston heard a prolonged hiss of gas, and then mud erupted from the derrick.
"Sort of a black rain," Landry recalled. He'd been mudded before, but it had always been from a broken hose.
He sounded the general alarm to muster off-duty crew, and then radioed the Deepwater Horizon. Trouble with the well, he was told.
"They said to go 500 meters away and stand by. . . . I heard the concern in the voice of the operator."
Landry, a captain who'd been supplying drilling rigs for 14 years, had never seen anything quite like this. He ordered the mud hose uncoupled and made ready to move.
A mile below on the seabed, a torrent of gas had seeped into the drill pipe, shot through a malfunctioning blowout preventer and bulldozed through the remaining mud, experts now think.
Paul Erickson, the chief mate aboard the Bankston, had noticed seagulls and egrets swarming the rig lately. Now, with a cloud of heavy gas settling over the rig and a geyser spewing from the derrick, he saw birds falling from the sky like feathery hail.
Gas apparently was seeping into the rig's main engines, too; their mechanical tempo surged as they fed on it.
At 9:53 p.m., two or three minutes after the gas began venting, Landry saw a green flash on the rig's deck, followed by two thunderous concussions. First the main engines ignited, followed seconds later by a blast in the mud room.
The explosions staggered a small group of BP executives aboard the rig who'd come to salute it for its outstanding safety record.
Spotlights blinked off, and emergency lights snapped on.
"Mayday! Mayday! Mayday!" Landry heard on the radio. "Bridge on fire. Abandon ship."
The Bankston's crew launched a boat to meet life rafts and pick up crewmen, some wearing only their skivvies. A few leaped from the rig's deck into the now-fiery waters of the Gulf.
A ravenous blaze feasted on the rig's many combustibles. Within minutes, the inferno engulfed the tall derrick and clawed into the sky.
Crewmen aboard the rig Helix Q4000, stationed 35 miles southwest of the Deepwater Horizon, gathered at the rail. They could see the firestorm — not just its glow, but the actual fireball — sparkling over the horizon.
By 11 p.m., 115 crewmen from the Deepwater Horizon were huddled aboard the Bankston.
On its wide, flat deck, Bankston engineer Anthony Gervasio overheard survivors speculating about what the gas had done.
"I was sitting around some gentlemen who said that the air blowing off it, because it was so calm out, it accumulated in the engine room, that the engine room had caught fire, blown up," he said.
A defiant fire raged for days aboard the Deepwater Horizon until finally the rig collapsed into the Gulf, where it had made its fortune — and those of its owners and operators — for nine years.
The Coast Guard searched for the next 80 hours by ship and air, but found no trace of the 11 missing crewmen.
Among those lost was mud man Gordon Jones, who'd started his shift early. His colleague, who'd gone back to his quarters early, survived.
(Washburn is a writer for The Charlotte Observer.)
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