Its a fairly involved process, which includes loading all their gear (and there is alot of it with winter gear and Katie's supply of liquid refreshments!) in to dry bags, then on to the boats. Then it is simple case of deliver people and stuff to the destination by performing a beach landing at the other end.
All of our potential holiday destinations involve landing on to the beach. The beach landings are done with the ribs, and it actually very straight forward, in a little tricky at times. The boat is driven bow first to the beach by the helmsman while the crewman trims the engines up. Trimming the outboards in this way reduces the vessels draft, and allows the boat to get further in to the beach without grounding the skegs or damaging the propellers. The negative effect is that the helmsman has markedly less control over the boat, particularly in applying astern power. This is because the prop is now at an awkward attitude and it's efficiency is greatly reduced. The helm (steering) also becomes heavier in this trim. It is for this reason that a slow and controlled approach is taken so as to minimise the need to use astern to slow the boat.
Cross winds present the most difficult approach. If the wind is blowing along the coast then keeping 90 degrees to the shore becomes a tricky task. If the boat should end up side on to the beach there is a serious risk of the vessel grounding and becoming prone to capsize in significant swell. The swell is the other serious factor. The to get personnel safely ashore (or in to sufficiently shallow water) and to keep the drives in the deeper water at the same time negates a stern-too approach. This leaves your transom vulnerable to being "pooped" (a genuine nautical term!) by the incoming swell. This can flood a boat or drive it too far ashore. The alternative would be to come in stern too riding to a kedge anchor laid offshore and trim the engines right out of the water. This isnt done because it has big downsides (like having no power available should the anchor fail at an inopportune moment, and frankly, its a bit of a faf) in reality, if the conditions on a particular shore are so severe as to raise concerns over a bow-to approach then the landing can wait!
I digress. Once the campers were ashore, Ashley (at the helm of the accompanying jet launch) took the opportunity to "map" the face of the Nordenskjold Glacier. The glacier face is only a mile or so to the south of Sorling (see my sorling camping trip blog for pics etc) So we proceeded South in to the ice. The rib is of no use in this exercise. The method used to give an indication of glacial retreat is to range the jet launch 1/4nm off the face by radar range, then navigate a course at this range taking GPS fixes at certain points en route. Plotting the positions, and the range will give an indication on the current location of the face. The accuracy is limited with this method because of GPS inaccuracy (which according to the Royal Navy who have spent alot of time charting SG can be often upto 500m!) and one or two other inaccuracies. However, Ashley does an admirable job in making the readings as accurate as possible, and it does give reasonable results. The Neumayer glacier, mapped in this way a few months back, is known from other surveys, known to receeding at up to 360m per year, and Ashleys survey did confirm this ball park figure.
As you may have gathered, the radarless rib is redundant during this kind of work, so time to practice some spirited manoeuvring......
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| Nordenskjold Glacier from the jet boat - Photo Sam Crimmin |
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| Somebody let the plug out? |
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