Bungees and tennis balls
An alternative on a local level would be to have all regular racers do a 500 meter or ~ 2 minute distance sprint in their boats. Then, add bungees and tennis balls to the hull until about even in speed. Not much fun to paddle with no glide, but for a local fun event, it puts the competition back into a pack of paddlers.
Speed/Length Ratio
Hull speed is not a limit. Most of us can sprint past hull speed pretty easily. Only the faster paddlers hold speeds above it.
The usual formula given for hull speed puts it at a speed to length (S/L) ration of 1.34. That number is a function of wave propagation.
Olympic K1s regularly hit S/L of 2.2 - well over hull speed (as in 164% of hull speed).
Other related tidbit: Stern squat generally begins around S/L 1.0 (sq rt of LWL).
Displacement increases form here to somewhere around S/L 2.2 then begins to decrease. I think the number for the point displacement returns to normal - and then begins to decrease (the semi-planing zone - not to be confused with true planing)- may be lower for narrow kayaks (nothing to base that on)- and within the speed ranges the top paddlers hit. Drag still increases with speed in that zone - but at a reduced rate (the curve flattens a bit). Not really useful info for us mere mortals - but I suspect the better paddlers using higher end boats spend some time in this zone.
seconded
I want to further emphasize the motor. Barton is a great example but many view him as just about supernatural in a boat. The rule applies to mere mortals like us as well. I made massive gains in my Q600 before started paddling surfski.
Over a Bogey length race, my surfski is only about 10-12minutes faster than my Q600. The differences within the touring class are smaller.
Getting a faster boat within a class is only going to get a paddler a minute or two. If someone paddling a fast touring kayak is 45-50 minutes back of the overall leaders then that paddler stands to gain a LOT more time through diligent training than through buying a faster boat.
Probably the message
to this little subthread is that it’s all too easy to overstate the effects of the hull-speed formula as is contributes to total drag.
Searching back through the archives I know you had your own formula to rank kayaks that mostly was based on lwl/bwl ratio.
Mike
Kayak classification
Hasn’t anyone else stumbled onto this site but me? It hasn’t been updated in a while, but has a lot of boats on it.
http://www.soundrowers.org/yakclass.htm