NOVA Online | Into the Abyss

menu (see bottom of page for text links)

ROPOS under repair.

The ROPOS Guys
by Peter Tyson
June 25, 1998

"A polite euphemism would be it was 'extensively damaged.'" Kim Wallace, a lithe, mustachioed ROPOS pilot-in-training and electrical technician, is telling me about an accident with the remotely operated vehicle—actually, with the cage from which it is deployed on the seafloor. The accident occurred during the robot's recent trip to the Indian Ocean.

"Torn to shreds is what it was," he says, smiling without much humor. We're standing in the Thompson's laboratory, a few steps from the stern deck, where the ROPOS and its cage lie as if in state. Members of the eight-person ROPOS team keep sweeping through the lab, wielding unidentifiable parts and concentrated looks. They're busily reassembling the robot and its damaged cage for tomorrow's departure.

It seems that while ROPOS was "flying" up a slope 2,300 feet down on the Southwest Indian Ridge, a spreading center near Madagascar, its sonar suddenly "crapped out," as Wallace puts it. The vehicle stopped but the cage to which it is tethered (and which in turn is tethered to the ship), kept going, blind as a bat without echolocation. It slammed into a wall of rock, mutilating its superstructure. I can see it out on the ship's fantail right now, half of it spanking new, the other half still showing nasty scars from the crash.

Loading the Thompson.

As if the crippled cage isn't enough to keep them busy, the ROPOS guys are having tether problems. (The "tether" is the cable between the robot and the cage, the "umbilical" the cable from the cage to the ship.) "It gets abused," Wallace says of the tether. "It gets yanked, pulled, and wound around features on the bottom." Conductors inside the cable nearest the robot begin to part, causing the cable to heat up. ROPOS' handlers then have to cut off the damaged portion. In the Indian Ocean, Wallace says, "it just got shorter and shorter and shorter." By the end of the cruise, a tether that was 1,000 feet long when new had shrunk to about 100 feet.

So from the middle of the Indian Ocean, Keith Shepherd phoned the company that makes the tethers and ordered a new one. For which we're now waiting. Not much time left; we're supposed to shove off tomorrow.

"You're expecting it today?" I ask Wallace.

"No, a week ago," he says, again with that mirthless smile. Turns out the tether company is in England, and they're having trouble making a new one. So it's decided—as if there is any choice—that the ROPOS crew will have to rely on two old spares before the new tether arrives in Seattle and can be shipped out on the Tully, the other ship on this expedition. Even as I write, one of those old spares is being wound onto a drum on the cage.

If these ROPOS guys are like so many worker ants, slaving away in the nest, there are plenty of soldier ants streaming to and fro along the gangway, bringing computers and boxes and luggage on board. All day long, through the light rain we had earlier and in the pupil-pinching sun now in mid-afternoon, scientists, students, filmmakers and crewmembers have been passing one another on the narrow steel walkway, keeping one eye peeled for the business end of a crane being used now and then by the ROPOS guys.

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)

The Mission | Life in the Abyss | The Last Frontier | Dispatches
E-mail | Resources | Table of Contents | Abyss Home