charles_reed
Active member
Hmmm. And I thought boats were designed to stand on their keels, while the pads were merely to stabilise the vessel laterally. Of course, drying out alongside there aren't many pads around, so a line ashore is in order.
Lifting by pads puts stress where it's not designed to be borne, in a small area of contact, however big the pads are. Hence the strong preference for slings, which mould to fit a large area of pressure.
If you think about keels usually hang FROM the boat rather than supporting the boat, just as sailplane wings are designed for loading from below but won't stand much of a weight from above.
One might decry the quality of boat construction that allows the keel to "punch through" a boat bottom, but a tour of many Greek yards, where the boat weight is taken on the keel, shows a definite deflection in the keel area of the hull.
Unfortunately it's unlikely that the provision of a Travelift will obviate the problems at Messolonghi as, to obtain the greatest space-efficiency of boat-storage, a trailer will continue to be used.
If you care to work out the footprint needed for depositing boats using a trailer cf a Travelift the former gives about 140% space-utilisation of the latter.
I have been assured that the trailer at Messolonghi is a copy (however inefficient) of one widely used in the Netherlands. If that is so the critical factor that has been overlooked is that mediterranean boats tend to being larger than those in N European waters.
AWBs, with an egg-box bottom construction, will probably not be adversely affected by the trailer - however those of an old-fashioned floor/stringer bottom will, especially where the pads cannot be situated under a floor.
Composites can undergo considerable deflection without immediate delamination but, appreciable continued deflection will usually result in progressive deterioration.
A possible risk, for beamy boats, especially with "biscuit-lid" hull-deck joins, with unspaced slings is damage to and leaks at the join - probably most at risk are the very AWBs already referred to. Fortunately, when Christos is driving the Messolonghi crane, they are usually used - with a Travelift this problem does not occur.
Regarding insurance stipulations that the boats are on concreted hard standings, there will be a very limited number of Greek yards that can offer that. Maybe a ploy to evade obligations, rather than a cogent requirement?