Changing 25M to 100M tether back and forth


I have pre-ordered the Trident with the 100M tether option since I am planning some expeditions down to 80M next summer. The question is how easy is it to change the tether on the fly? (or does one need to change it in a controlled environment?)

Egill Ibsen


I believe thhe plan is that the tether will be swappable in the field in just a couple minutes.


That is great news. Looking forward to receive the Trident.

Thank you for the reply.


Would you change the tether depending on which depth you were operating? I was thinking of keeping one of each as well to reduce weight and make management easier but then again you might just spool it in and out as needed.

Also: interested to hear what you’re thinking about that’s at 80m, anything cool?


Yes. The 100m tether would only be used occationally. I might even buy another and cut it in various extension lenths for different types of expetitions.

Our 80m expetition is actually an educated guess. The max depth in that area is 120m but we will be searching for an 16th century ship in that particular expedition. If the Trident arrives in time for next summer and all goes as planned I will write about the project in Open Explorer. I can not reveal more at this time.


Using one tether of 100m, but mostly using it for 20-30m deployments may have wear implications.
I see a lot of crane work. hundreds of metres of cable are spooled onto the crane drum, but most of the wear is on the other end of the cable, so every few hundred lifts (actually tonnes-lifted integrated against km of cable movement), the loose end of the cable is chopped, re-terminated into the travelling blocks, and more spooled off the storage drum as the measurement system is re-zeroed. If you were doing a lot of short deployments, you’d probably want to keep track of this level of usage to keep your preventative maintenance up to scratch.



The other day I was looking at one of these spools and thought to myself that this would be the best thing for the 100m. You could play it out and back in easily. I never stopped to think that it might wear it out quickly…good thing the new NBT isn’t as expensive as some of the cabling out there.


I am planning to use the WiFi buoy as much as possible and therefore the “need” to use the 100m tether only occasionally. I will wait for the Trident before I plan any further.