Steel or Grp

[Lucas13]

Many steel boats seem to be built with a high stern, for strength, but have a sunken central cockpit, which makes them less safe if swamped by waves. Modern GRP boats have a lower stern with an open drain beneath the seat. Are there any steel boats designed the same way?

 

[AndrewB]

I think this is primarily a difference between long-distance crusing boats, and cruiser-racers, rather than between steel and GRP.

Conventional thinking is that in a short-handed long-distance cruising boat, you want the cockpit really well-protected, and small so that if it does fill it will not encumber the yacht. The risk is against being 'pooped', where a breaking wave from behind swamps the yacht.

The modern long-distance racing yachts challenge the traditional view. Broaching, rather than pooping, is the greater risk. But I think the old rule probably still applies to smaller, slower yachts. Of course, a very small cockpit can be inconvenient when in port. And making big enough cockpit drains has always been an issue.

 

[Strathglass]

Lucas
Steel tends to be better on larger yachts because of it's weight. Many steel boats are used by cruising people and because of that they are more concerned with internal space than ultimate speed and sailing performance. Often it is the mother of the family who goes for a large aft cabin. Hence, steel cruising boats are often built with a centre cockpit.
Sometimes this cockpit is quite low with poor freeboard but quite often the centre cockpit is very high up and miles above the water. Some people like to be far away from the water when they are sailing.
There are also many GRP cruising yachts also built with centre cockpits. You can still have self draining centre cockpits yachts.

Grp yachts can be built lighter and they are often built for racing. When a racing yacht is designed other things become more important. Too much weight at the ends makes the boat less dynamic and it does not react so quickly, especially if the sea is rough weight at the ends slows it down. Thus tiny aft and forward cabins and no heavy superstructure with all the weight low down in the middle. The topsides of the boat are kept as low as possible to reduce windage. Sometimes this makes for a very wet boat like the Contessa 32. A rear cockpit is often used because it is easier to see and adjust the sails and a big cockpit makes more room for the crew. Fully open transoms are fine in a racing boat but in a following sea can be quite frightning. Yacht shapes have chanced dramatically over the last few years. But remember that a light flat boat may be much faster in normal conditions but it may demand continous attention to the helm compared to a heavier cruising boat especially when the wind comes up.

There are plenty of steel boats built with an aft cockpit but until they are above about 12 metres Loa they are much heavier and thus slower than GRP yachts.

Many materials can be used to build yachts (even wood) but it is the shape of a yacht which determines it use not what the hull is made from.

Does that answer your question Lucas?

Iain

<P ID="edit"><FONT SIZE=-1>Edited by iainsimpson on 19/01/2003 18:39 (server time).</FONT></P>