Are heavier kayaks more efficient cruisers

Advice
#1

The argument would be that once up to speed, they maintain that speed easier due to greater momentum…in the same way that it is often pointed out that large commercial ships laden with cargo may take several miles to come to a complete stop.

I can think of counterarguments. For example, (a) a heavier boat would sit lower in the water and therefore have more wetted surface area (drag). (B) Although the loss of speed between strokes might be smaller, getting back up to that speed would require more effort. (C) Plastic boats are heavier than glass boats and are said to flex more as they accelerate through the water which is a diversion of energy away from forward propulsion. These all seem like very small effects, maybe not noticeable. I don’t know. Is it a wash? Is there a clear winner?

#2

I do not know the answer to this, but I would think that hull geometry (hydro-dynamics) is probably more important. My reasoning is that a battle ship and a tanker ship can weigh the same, but the Battle Ship is faster, Some may simply be because of more powerful engines and larger screws, but the hulls of the 2 ship are designated for different purposes. In parallel, a stronger and more efficient paddler is going to be faster then a weaker one, even if the stronger paddler’s kayak is not as sleek. Bigger engine driving a bigger “propeller” so to speak.

My wife is faster then I am when paddling 2 kayaks that are identical, because she is good at handling the paddle and also because she is lighter then I am, making the total weight going through the water less, sinking the hull a bit less deeply so she needs to move less water. BUT over a 5-10 hour trip she can’t keep up with me so I have to slow down for her because I have more power and longer endurance. So “fast” is a term that needs to be defined. Anna is a faster paddler then I am in the short run and I am faster then she is over longer distances.

When 2 kayaks are of the same hull design I wonder how much effect a few pounds less can make. Some to be sure, if ALL other factors are the same, but that is a scenario that is very unlikely to happen.

What is being moved over the water is the weight of the kayak, the paddler, the paddle, the clothing, water for drinking, food, emergency gear, PFD, and a few other small items. I weigh 186 pounds. My kayak empty weight 63. I wear about 8 pounds of clothing. Add to that my PFD and knife. I carry a minimum of 1/2 gallon of drinking water and sometimes up to 3 gallons. I carry a bit of food. I carry a few carabiners and some rope, a spare paddle, a paddle float and bilge pump. On trips I carry a small tent and a sleeping bag as well as a thin ground mat. So if I add it all up I am moving a load of around 300-320 pounds. If I were to get a carbon fiber Kayak of the same size as my poly kayak. I would drop about 12 pounds. Or to put it exactly a move to a carbon fiber kayak will drop about 4% of the load.

I can’t say because I don’t own such a kayak and I can’t afford one, so I am not likely to ever know for sure, but a 4% drop at the very best could make me what…4% faster? At the max?

I paddle at an average speed when cruising of around 3.4 MPH That comes out to 239 yards farther every hour. Over a 10 hour paddle that’s 2390 yards. 1760 yards is a mile, so it may be that if all other factors were equal the lighter kayak would be noticeably faster. Noticeably but not dramatically. However if I were bucking choppy water it may be the 4% heavier craft may get through them better?

I don’t know.

It’s an interesting study, but the main factor is and will always be the engine (man or woman) who is doing the paddling and the hydro-dynamics of the hull. Hulls can be matched------- but people not as much.

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#3

Its pretty simple to test it, right? Test 1: day trip, light kayak. Test 2: camping trip, 40+ lbs heavier.

In practice I’ve never noticed a difference in speed. What I did notice: acceleration is slower, boat is more stable in waves.

#4

Length equals speed.
Weight puts you lower in the water and creates more drag and friction.

#5

If heavier meant more efficient, why are racing boats as light as possible? Increasing efficiency would allow more power to be applied to going faster.

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#6

I don’t take it as a given that top speed and cruising efficiency (energy required to maintain a given speed) are well correlated. A fighter aircraft has a much greater top speed than a glider, for example, but the latter uses infinitely less fuel to fly at a lower speed.

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#7

If the kayak is heavy enough, it sinks.

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#8

I can definitively state from paddling my boat empty of gear and paddling it fully loaded with a weeks worth of camping gear that the loaded boat is slower as measured by GPS and using the same amount of effort. Often by 0.5 mph or more. The loaded boat displaces more water and sits lower. That additional water must be pushed aside to make forward progress.

Additional mass may help you to glide further if all other things were equal, but more is lost in the increased resistance provided by the additional water that must be moved aside and the energy required to do it.

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#9

Well, maybe… if I’m going through the water plants camping in the Okefenokee swamp I take the canoe and load it up heavy and try my best to blast through.

Kayaking not so much. The heavier boats seem to coast straight…when you want them to turn. Do they resist wind round up? …no, mine don’t. Load it up a lot sure it resists rounding up, but it also resists turning and avoiding things like trees, stumps, etc. Acceleration is hampered.

I think lighter is better. Especially at the time you load the boat. But paddler’s strength and abilities over shadow a lot of things once in the water.

#10

My subjective experience in the solo canoe world is that there MIGHT be cases where a loaded boat cruises faster. I’ve done a lot of paddling with and without a 60-70 pound dog. The efficient range for many solos is around 160-180 on the low end to 260-320. So the dog’s weight takes me from around the bottom to the top of the design range of most solo canoes. Many solos have more acceleration that they need (zero effort, like a leaf on the water) so I actually like the increased effort to accelerate and I love the extra momentum (dog’s weight adds 20-25% to momentum). The higher effort (at lower cadence) with better glide seems to match my body better. Plus empty solo canoes are designed bow light for safety so a dog’s weight often makes the trim ideal for speed (slightly bow down). And WL length will increase with a little weight, not sure about L/W ratios, and it seems like the skin friction penalty could be relatively small since shape effects may dominate at (higher) cruising speeds.

#11

You think those are a good analogy for kayaks?

Feels like comparing a cigarette boat to a canoe, to me

#12

So does that mean heavier kayaks are less efficient or heavier kayakers?

#13

Not sure, but I think some of the efficiency may be impacted by conditions. I know in rowing too light can be a negative in chop where a heavier boat will carry its momentum through that chop.

#14

or a racing boat to a kayak

#15

In any racing I can think of weight is your enemy. Nobody is seriously racing plastic or heavy hulls.

Raced offshore boats for years tons of water conditions weight never helped anyone going through waves.

If by effiecent you mean speed I’d say no.

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#16

I wasn’t thinking speed as much as energy expended per distance covered.

#17

More weight takes more energy or power.

Think of two balls one heavy and one lighter release them at the same speed heavier will go further. More power to release it at the same speed. Load you kayak with gear it’s slower and takes more power to move. You may feel a smoother ride because of weight like a power boat.

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#18

In a tandem my wife and I are considerably faster. Thats two times the paddlers but also twice the weight so that should be roughly a push between 2 and 1 person craft as far as that trade off goes. The difference is length I think. We are one long boat (13.5) so despite being a heavy (80ish lbs) hull plus two somewhat heavy people in it our actual cruising speed is quite fast.

#19

13.4 feet is short for a tandem. You’re just gaining a paddler.

#20

The answer is simple. No.

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