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This boat was painted Maroon on one side and Navy Blue on the other. This caused a certain amount of confusion to other competitors.

This boat had the underwater shape of Rage (N454) but a much wider beam. I think the first owners were Desmond Stocks and Annette Wiggins who owned Rage.

The first owner was Cmdr N E Morley at one time Chairman of NTOA 

NTOA note: Norman Morley Chairman 1958-1959.

I believe the design is a Proctor Mk 2. It's first owner was Peter Martin and sailed at Frensham Pond.

See Fran's message from last Sept / Oct

South Gloucestershire finish July 25th 2008

Consider getting two strain gauges - one for low speed - one for high. It may be easier to try two boats at a time on a pivoted beam so that one can measure differential drag. The strain gauges would give drag v speed curve for one hull with say 2% accuracy. With two boats, keeping one as a reference design, you could plot % difference in drag v speed to much higher accuracy than by comparing separate drag v speed curves.

Ideal conditions for testing would be Beaufort force 0 - 1. Ideal conditions for sailing force 2 - ?

Jimbo has the correct interpretation of my views. I am aware that heavier older boats have a larger design displacement than modern boats. If we are looking at differing hull designs we should take out hull weight as a variable and test heavy hulls with lighter crew / ballast in them so they all have the same displacement. This displacement could well be that of a modern boat with crew rather than of an old boat with crew.

We could (but probably don't) have a situation where an older hull design built to the current weight rules has less drag than a modern design; but the extra weight in the older boat increases the drag so that it exceeds that of the modern boat.

I think testing should be at constant all up weight (displacement). Then we would get a better idea of how good older designs are rather that how much less drag a lighter weight boat has.

Illegal only while racing surely?

There are two issues here. How accurate is a GPS of the hand held type, and how often does it give a fix?

For speed measurements you take the distance between two positions and divide by the time interval. For World Sailing Speed Records, the distance has to be at least 500 metres. This is about a minute for a flat out N12. With a GPS, the shorter the time interval, the larger the uncertainty in the speed calculation.

For a given N12 the limiting speed is likely to be due to
a) gear breakage
b) boat capsizing to leeward
c) boat nose diving

a) and b) can be solved by strong enough gear and bearing away as wind speed increases. Thus the limit is likely to be nose diving. Wide beam at the stern and "transom hanging" will help. Other features like a larger jib to generate some lift up front and hull design I will leave to the experts!

Does the inside of the boat have ribs every three or four inches apart to hold the clinker planks together using a copper rivet through two overlapping planks and the rib?

Or are the clinker planks just glued to each other and screwed at the ends into the stem piece and the transom?

This link may help.

http://www.national12.org/downloads/amateur_building-2004v1-foam_sandwich[LowRes].pdf

Put a sandbag on each post to avoid denting the mast. Bounce gently at first then increasing the bend. Check frequently to see when the mast straightens.