Yacht Design Drawings

I originally contacted the designer, Ron Holland - from New Zealand, now in Ireland, who after searching his files couldn't find any designs for the Holland or Eygthene.

I found hull design scans on the Eygthene Forum, which was the 24 foot for-runner of the Holland 25. I took those 8 x A4 scans and pasted them (as well as possible) together in Photoshop, then traced them in AutoCAD.

In AutoCAD, I was then able to stretch, extend, tweak and largely guestimate the hull lines that you can see to the right. If you click on that graphic, it will load an A4 PDF that is much clearer. This shows how beamy the Holland 25 is but with a very 'fish bowl' style beam cross section. Although this gives a wide deck, the beam at the waterline is no where near as wide.

I could not find any original sailplan drawings so I had to work from mainsail P and a rough measure of the three pieces of old broken mast. I then decided to lower both the mast and sail-plan to gain stability. Originally, the rig was a fractional with a tapering mast over 11.2 m from keel step. I decided to change that to a 10 m from keel step masthead and I had 2.5m² cut off the foot of the main sail to allow the mast to be built lower and closer to the previous top of the fractional fore-triangle (over 1 metre lower). Theory gives this less heeling due to lower centre of side force on the sails but how it affects the balance of the rig I won't know till extensive sailing. If my theory calculations are right, we should be able to regain ballance by mast rake of about 300 mm at the top, moving the centre of effort back about 100 mm - time will tell?

You can see the resultant mast and sail plan in the graphic to the right. Click graphic for an A4 PDF verison. Note: the boom has a higher leech as I took more off the leech than luff to keep the centre of force low but gain some headroom. OK,so I won't have the Quarter Tonner racer it once was, but I also don't intend racing with five crew on the rail either, let alone when out for a cruise with Moira. It should be a tamer, safer and less prone to knock down yacht, which is good and if we can sail it flatter, it may even be faster!

This could give a cheap method of detuning a 3/4 fractional rig by cutting the mast down to close to fore-triangle so perhaps a 9/10th rig, for cruising or safer sailing. Here's hoping we'll find it works. We have a number of other Holland 25 yachts nearby to hopefully compare against (mainly masthead from original). Theory and practice hopefully will be close.