20,000 Pounds of Tension
Le Olson (in yellow hat) brings the Roane chimney aboard.
by Peter Tyson
July 8, 1998
The tension in the air was arguably as great as that on the line. And considering the tension on the line had just reached 8,000 pounds, you can imagine the kind of tension in the air I'm talking about.
It was 10:45 this morning, and we were back on the fantail of the Tully. As it turned out, we were on the brink of recovering a second black smoker chimney, although it didn't look quite so positive at the moment. The yellow line was taut as a high wire; clearly it was fixed fast to Roane, as John Delaney had dubbed this chimney. But even at 8,000 pounds of tension, it hadn't succeeding in breaking the chimney free from its moorings. Would Delaney's gamble to attempt removal without using the chainsaw pay off? Or would Roane refuse to let go, effectively anchoring us to the seafloor?
Wearing a look of concentrated concern, Le Olson, the engineer from the University of Washington's Applied Physics Lab who's in charge of recovery operations, kept his eye fixed on the tension gauge on the FADOSS. Vaguely resembling a Dr. Seuss contraption, the Fly Away Deep Ocean Salvage System was a pea-green machine with large flywheels that routed the incoming yellow line this way and that until it spilled out the back, where the Tully crew fed it into a basket. At the center of the machine lay what looked like an oversized bike pump. This was the compensator, which was now coping with the tension the winch was using to try to break Roane free.
The gauge climbed to 10,000 pounds. Vern Miller, Olson's associate, raised two hands with his fingers splayed to convey that figure across the fantail. He was smiling, which I took to be a good sign. Perhaps, despite Olson's pensive expression, this was par for the course. I couldn't ask anyone, because the winch engine was once again roaring to beat the band, and everyone either had foam plugs jammed into his ears or wore those big headphone-like mufflers. All I could do was smile stupidly at people in the know and try to read their lips as they yelled to other people in the know.
I did know that there were two key differences between Roane and Phang, the chimney we pulled up three days ago. For one thing, unlike Phang, Roane was alive. It was no smokestack, with the kind of billowing black smoke that gives these chimneys their name. But it was decidedly active, with diffuse plumes of superheated water shimmering up its flanks. We measured those plumes last night using ROPOS. They reached 176°F, and that's amidst 35°F sea water. So you can imagine how hot Roane must have been on the inside. Roane's activity affected our attempt in two ways. First, active chimneys are structurally weaker than inactive ones, and thus Roane might break apart like a wet sandcastle. Second, if the superheated water inside flashed to steam on the way up, the force of the water's expansion, which can be as much as 100 to one, could also threaten to shatter the structure.
John Delaney inspects Roane aboard the CCGS John P Tully.
The second difference was that Roane was bigger than Phang. Much bigger. Size does matter when you're lifting heavy objects off the seafloor. Phang weighed about 1,200 pounds out of water. Estimates for Roane out of water, if we succeeding in retrieving the whole shebang, were on the order of 7,000 pounds.
At ten of eleven, Vern Miller raised two hands, then one hand: 15,000 pounds. He had stopped smiling. Everyone else looked either anxious or affectedly not. Even if it hadn't been for the clamor of the winch, I think silence would have reigned. My eyes flashed between my watch and the tension gauge.
10:54 a.m. 17,000 pounds.
A small crowd of people stood high above the fantail. They, too, wore earplugs or mufflers, and looked anxious or affectedly not. I risked disturbing Miller by yelling into his ear, "What's going on?"
He yelled back, "It's just not breaking. Right now, we're attached to the whole thing." He meant the wide base of the chimney, not just the spire we were after. But he might as well have meant the ocean floor.
10:58 a.m. 18,000 pounds.
The gauge went to 65,000 pounds, so this was probably small potatoes for it. But the winch was rated at 30,000 pounds and the A-frame at 28,000 pounds. We were starting to push the envelope.
At 11:00 precisely, the gauge tipped past 20,000 pounds. Olson waved Delaney into the relative quiet of the lab. I followed, along with four or five others. Olson began to suggest the alternatives: slack off and reload; hold tension for awhile longer; or cut the line. I was just beginning to wonder if Delaney was regretting his decision to forgo the chainsaw when Miller burst into the room.
"Le, I think it just broke!"
Expedition co-leaders Ed Mathez (left) and John Delaney head to the Tully for the attempt on Roane.
Everyone dashed outside. The gauge read 15,000 pounds and was going down fast.
The mood on deck did a back flip. Frowns became grins, tentative touches on shoulders became thunderous pats on the back. With the winch still precluding speech, Olson grabbed the arm of Ed Mathez, mouthed the words "Got something," and flashed his trademark grin. I could see waves of relief washing over both Delaney and Deb Kelley. Olson later told me simply, "Spirits soared."
We didn't know what we had; we only knew the chimney had given way. The FADOSS compensator had locked up, so it was impossible to know how much it weighed. How big was it? Did we get all of it, or some of it, or none of it? The complete loss of Roane was possible, but the general mood seemed to sweep such concerns aside.
In Scottish Highland folklore, Roane are seals that are actually fairies who dress in sealskins so they can pass through water. They are the kindest off all fairy people, because they never avenge themselves of the people who hunt them. (I know this from the book Abbey Lubbers, Banshees, and Boggarts: An Illustrated Encyclopedia of Fairies, by Katharine Briggs, which somehow got onto this ship and has provided names for one or two chimneys.)
Well, Roane the chimney did not avenge itself of its captors by shattering or vanishing altogether in the depths. Instead, 45 minutes after the winch wrenched it free, Roane rose out of the ocean at the stern of the Tully. As we had expected, the unsupported cone was missing, and what came up was in two pieces. But a good 4,050 pounds of chimney, solid as a redwood and still smoking, was lowered onto the deck.
Delaney and Kelley rushed forward and plunged a temperature probe into the smoking orifice. It registered 194°F, and that was after an hour in near-freezing water and another half hour in cool air. I stuck my hand in the fist-sized opening; it felt like a sauna in there. Such heat helped give life to the forest of straw-like tubeworms clinging to the chimney's sides. A black mineral, which the geologist Mathez told me was probably wurtzite with a little sphalerite thrown in for good measure, glittered inside the opening, the last metal this smoker would ever precipitate.
Instead, this unassuming rock from the abyss will precipitate something finer: scientific understanding and public education. As we watched ROPOS survey Roane's cleanly sheared stump on the seafloor tonight, Mathez, with his expedition co-leader Delaney nodding in agreement, told me that "we have accomplished one of the major scientific goals of the expedition, recovering a live sample." A sample that, in addition to serving as a premier scientific specimen, has supplanted Phang as the chimney-of-choice for display in the American Museum.
Unless we find something even better, that is.
Peter Tyson is Online Producer of NOVA.
The Tug of the Thompson (June 23)
The ROPOS Guys (June 25)
In the Juan de Fuca Strait (June 27)
Special Report: A Visit To Atlantis (June 29)
Dive 440 (July 1)
Rescue at Sea (July 2)
What's Your Position? (July 4)
Phang! (July 5)
20,000 Pounds of Tension (July 8)
Four for Four (July 11)
Thrown Overboard (July 13)
Was Grandma a Hyperthermophile? (July 15)
Swing of the Yo-Yo (July 18)
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