In addition to the Brit upswept bow vs plumb bow in the 18X vs Brit thread, I noticed a striking difference in the top views of these and similar boats. Both the 18X and Q700 are much fuller it the top view at both bow and stern than a number of the Brit boats; Nordkapp, Aquanaut, Explorer, etc. The Brit boats have exceedingly fine ends; the NDK boats only slightly fuller than the Valley boats. This includes even the ‘Greenland’ style boats, Greenlander series and NDK Q-boat. (Each web site gives top and side views.)
I don’t have data but do believe the 18X and Q700 are faster at top speed, and more efficient at a fast touring speed, say, 4 to 5 kts. I wonder what the effect of the fuller ends is on handling characteristics.
The 18 and QCC
Have a more rocking horse moment in a chop where the Brit boats ride smoother… JMHO
They are not just fuller
– Last Updated: Mar-16-09 4:51 PM EST –
They are also more vertical as opposed to the shape most other hulls have as you look from the ends towards the middle. The bottom characteristics also affect the handling greatly. I have not seen a head to head photo of the hulls of the *current* 18x and QCC700 but having briefly test-paddled both I think they have somewhat different handling and hull shapes, especially near the cockpit.
How does it affect handling compared to brits? The video shows it pretty well, I think (although I agree than the Epic is traveling a a little easier path than the brit boat so differences are exagerated IMO in the video)... Now does this type of handling help or hinder totally depends on the situation and intended use...
"compared to brits"
Which Brit boats?
My Romany handles very differently than my Aquanaut and both handle very differently than my Nordkapp LV.
My Aquanaut has about the same amount of rocker as a Q700 and has much fuller ends than my Nordlow. Sit my Romany or 'kapp LV on flat pavement and very little of the keel is on the ground. Compare them to either my wife’s Explorer LV or Vela and one would note more differences. And we are only talking about the 5 Brit boat models in our small fleet.
Different Brit boat designs/models have somewhat different performance personalities.
too me
To me the boats that have the ends smooshed laterally with fat middles paddle like 12-13’ boats with long bits attached to the ends.
Of boats with upswept ends I prefer boats like the NF Silhouette/Legend and Hawk type “greenland” boats. These boats carry some volume into the ends which makes them faster and smoother.
I’m not going to define
what a “brit” boat is beyond just saying it typically has upswept bow, some rocker, is typically thin and of low volume towards the last foot or so in the front and rear. When looked from the front it looks like a curved/concave V similar to an aircraft carrier before it gets really plumb towards the cockpit.
The Epics in question have parallel sides or gently slopin V in the same area. If anything, they are convex there.
Looked from above, the “brits” look like they are pinched (e.g. concave) from both ends where the Epics look like they are extruded from the middle all the way to the ends and even convex a little.
Rocker is a separate issue and either design can have it.
Of course, there are variations, which only epmhasize one or another characteristic.
Note I did not say one is better, so let’s not get defensive or offensive one way or another -
They are different and each has its advantages and specialty.
I tend to agree scombird
Very fine thin ends equate to a lower Cp and less Frictional Resistance, BUT, they behave like a shorter LWL beacause in effect they “are”. Fuller ends have a higher Cp and more Frictional Resistance, BUT present a longer LWL to the water and thus can be pushed to a higher Potential Speed.
Less powerful paddlers can benefit from low Cp hulls as they are more efficient for them at cruising speeds below 4 knots or so…but they are limited at higher speeds. Stonger paddlers benefit from a longer LWL in sprinting and fast touring.
Elfin…
– Last Updated: Mar-17-09 7:24 AM EST –
Many, myself included, tend to use the term 'Brit boat' to refer to the kayaks derived from West Greenland hunting boats and the Anas Acuta - boats whose appearance is rather elfin.
Of course not all British sea kayaks are elfin:
yeah yeah, epic qcc blah blah blah
…but can you get footwear to match your kayak if you buy one of those?
http://www.mooncostumes.com/image/4837
As salty said…
“3) Prismatic Coefficient (Cp) is the volume (V) divided by Lwl x Ax. It displays the ratio of the underwater volume of the hull to a rectangular block of the same overall length as the underbody and with cross-sectional area equal to the largest underwater section of the hull. This is used to evaluate the distribution of the volume of the underbody. A low Cp indicates a full mid-section and fine ends, a high Cp indicates a boat with fuller ends. Planing hulls and other highspeed hulls tend towards a higher Cp. Efficient displacement hulls travelling at a low Froude number will tend to have a low Cp.”
Shoes to match your Epic or QCC kayak
not bad!
Some things should be left in the closet