I haven't paddled them together, but my all day speed in  the WD12 is 3.5 mph and my record for a short sprint was 6.5, both measured with GPS. A good fast speed for short distances (2 miles or less) is just over 4 mph. Maybe a Mill Creeker can give the matching numbers for their boat?

When I go with my wife (who paddles a 16LT) she routinely leaves me behind, even though she's sort of kid-sized (less than 5 ft. tall). She tried my WD12 and hated it, said it was like paddling a tank.

Laszlo

in boats there are two rules of thumb when comparing speed.

1) longer waterline = faster

2) narrower = faster (although I think that is more about the ratio of length to width)

In kayaks, a 2 person boat is also usually faster then a similar 1 person boat (twice the engine).  I have not measured the speeds of my Duck, but yes, my 17' 24" beam sea kayak easily out paces the duck.  does not mean that you cannot share an enjoyable paddle together, the person in the duck will just get a greater work out :)

 Hope that helps

Don't forget factor 3 - the hull shape (related to but not the same as narrowness). A shorter boat with less wetted area will go through the water faster than the longer boat with more wetted area when driven by the same power

Laszlo

Took my Wood Duck 10 out today with a GPS.  I am 180 lbs. and 6'1".

Paddled about 5 miles and felt really comfortable at 3.8 to 4 mph.  Staying over five mph was really good exercise(tough work for a 62 year old).

I am assuming a lighter person could go faster with less effort in calm conditions.

Rich

Rich, interesting you mentioned calm conditions.  I was on a trip in Lake Superior and it was uncharistically calm.  When I mentioned that we would make better time in the calm conditions, our guide (also a Dave) said that you actually make better time in rougher water as the boat has less wetted surface bouncing in and more importanly out of waves.  Dave studied nautical engineering and is now a professional guide with years and years of experience so I respect his opinion, it would be interesting to test to the two scenarios... perhaps we should call the Mythbusters!

I will definitely tune in if the Mythbusters settle that question.  Even if they don't find a scientific excuse to blow up the kayak at the end with 2 kilos of C4, though that is always my favorite part of the show.

The common wisdom is that seas slow a boat.  And certainly that is true for, for example, a sailing keelboat. and most other familiar cases.  But it would be fascinating to learn that kayaks don't follow the rule, though the explanation sounds a bit implausible to me for several reasons.

I'm reminded of the "common knowledge" that us old-timers grew up with, that a boat can't exceed its hull speed without planing.  True for most boats, but kayak racers turn in average speeds of up to 170% of hull speed without planing!  So kayaks don't always follow the "rules".

"Hull speed" is just a measure of how fast a wave can move. Longer waves move faster than shorter ones.

A pure displacement boat pushes water away from in front of it. The boat can't go any faster than the water it's pushing. It has to wait for its wave to get out of its way before it can move forward, so its speed limit is the speed of the wave.

A planing boat slides across the top of the water and is not affected by the speed of water getting out of its way.

A kayak also pushes a wave like a pure displacement boat, but because of its narrow hull it doesn't have to wait for the wave to get out of the way. Instead, it can slice through the wave and leave it behind, busting through the speed limit.

Laszlo

This has become a very interesting discussion!  When I mentioned "calm conditions", I was thinking of how tough it is for me to paddle against a strong wind and how much fun it is when the wind is helping.

Since I am not a kid anymore and do most of my kayaking on a tidal river with strong currents, I plan my longer trips carefully.  I usually go out about an hour before the end of the tide.  I go with the tide, and I come back after it has changed.  This sure beats bucking a tide that could theoretically exceed the Wood Duck's hull speed.

Rich