This morning, while changing shifts, the ship’s general alarm sounded.  Trying to remember if continuous sounding meant ‘fire’ or ‘abandon ship’, I met Jeffrey Lee (one of the ship’s engineers) in the hallway.  He seemed quite calm for either the ‘fire’ or ‘abandon ship’ scenario.  I asked him what was going on, and he replied there was a hatch on the rear deck, that when closed with too much force, somehow interferes with the ships phone system, causing the alarm to go off. 

Relived, but not sure if I was feeling any better, I returned to the computer lab where we were still surveying possible dredge sites.  The rough weather made deploying the dredge impossible, so we continued to map the area and scout out other possible dredge locations.

Picking a good dredge site is not as simple as pointing to a location on a map.  There are many factors that must be considered before we deploy the dredge.  For one thing, if there is any wind of substantial velocity, it is preferred that we dredge heading into it. The reason behind this is we have to back up (ie: the dredge gets stuck) the ship is the most maneuverable working against a headwind (this helps avoid wrapping the dredge cable around the propellers).

The other factors to consider when picking a dredge site are depth, ground composition, and slope.  The depth and ground composition are obvious, we can’t dredge past the length of cable we have, and we don’t want to dredge over a slope covered with coral which will snag the dredge, or at least prevent it from getting a good rock sample.

The other factor is slope.  The angle of the ground is very important when considering a potential dredge location.  Ideally, the dredge should be towed perpendicular to a ridge or incline, from low to high.  This is important because in addition to the relative angle between the dredge and ground being less severe, it makes it much easier to un-stick a stuck dredge.  When stuck on a slope you can back up and simply ‘pull’ it off horizontally.  On flat ground, reversing course usually just serves to tangle the dredge further, or wrap it around itself.

We continued to survey the rest of the day.  The weather became better, and the heavy weather procedures that kept had us inside were lifted, much to everyone’s delight. We were able to resume dredging operations and the lull that the storm provided allowed everyone an opportunity to catch up on reports, logs, programs, theses, and much needed sleep.

Blake English onboard the R/V Kilo Moana.