Hello all
What do you think about boats with a full buoyancy tank that runs the whole length of the cockpit, along the center line of the boat, and vertically goes from the floor to the underside of the benches?

Sure, the extra buoyancy is great, and it should help support the benches, and help with longitudinal stiffness, but does it help or hinder performance?
Ie. does it give paddlers something else to anchor themselves against, or does it get in the way.

I'd like to hear from anyone, with or without experience of this kind of boat.

What do you think about buoyancy in general?
Most makes of boats have very little buoyancy.
Isn't this just an accident waiting to happen?

Regards
Gareth

If it does not increase the weight of the boat then go ahead. If anything it would provide the boat with more structural rigidity.

Will it make a huge difference? in the rare occasions that the boats do capsize they already have buoyancy tanks on the ends so this doesn't really matter. The bulkheads under the seats have more to do with shipping the boats than buoyancy.

In short, my concern would be that after a huli the boat would want to float upside down and would be tough to re-right ....if it were rerighted but still full of water it may be unstable with the floatation on the bottom and may want to turn-turtle again....these would be undesirable aspects particulalry in cold water where paddlers may need to get back in the boat even if it has water in it.

Hello Anonymous and wet spot

Thanks for your input.
The buoyancy in the bow and stern is not enough to keep the boat afloat enough to keep any of paddlers' bodies out of the water.

How rare is it for dragon boats to sink?
It would be interesting to have some figures for this.
I come from a rowing background, and since 2007, all boats are supposed to be built with a lot of buoyancy, specifically, enough so that the top of the seat is no more than 5cm lower that the external water level. This is easy to do with rowing boats, and is absolutely impossible with dragon boats, but the more of the body that can be kept out of (cold) water, the higher the survival rate.
There have been court cases against clubs and coaches that allowed members to use boats that do not float.
How long before this happens in dragon boating?

I agree that with most makes of boats, the bulkheads under seats have more to do with shipping, than buoyancy, although every little helps.
Extending these buoyancy tanks along the length of the boat, or having tanks under every seat, adds a lot of buoyancy, but do they help or hinder the paddling.

Having a tank running the whole length of the boat, from the floor to the seat shouldn't make it any more difficult to right a boat capsized boat, but it would make the boat very "tippy" in teh first place, causing it to capsize, and also after it has been righted, as most of the water remaining in the boat will be on one side or the other.
To be useful, there needs to be a way to equalize the water on both side of the boats, such as a section where there is no bulkhead/tank.
And this would be best in the middle, where the floor is lowest.

Has anyone ever seen a dragon boat with Anderson type self bailers, as used on sailing dingies?
I haven't, but I wonder why not.
If you aren't familiar with them, they fit flush with the outside of the boat when closed, and can be easily opened from inside the boat. When open, and the boat is moving, they bail a lot of water.
Should be good for training, and might even improve speed in a race, despite the bailer sticking out a bit when open, as less (heavy) water is being carried from start to finish.

Regards
Gareth

The bailors you mention are used in most marathon canoes. They require both a minimum speed and some time to work (opening is pretty small). They must also be placed in the lowest point of the boat. They might be useful occasionally in DB ,perhaps a 2000m. I remember one mens' boat burying its bow in a 2000 at the Toronto club crews , almost sunk , got beat. Might have helped a bit but you are not going to let out much water in 500m.

I have always wondered why Dragon Boats don't use Anderson Bailers. They make a lot of sense and work great in dinghy's. Six would do the job and are controlled while paddling. As far as buoyancy is concerned, many high performance dinghies use an air pocket between the hull and the "deck". International 14 construction is the easiest example with a one or two inch air pocket exists between the two and offers increased buoyancy. The next question is when will another supplier begin building boats that are conpetitive with BUK's. It has been tried before however BUK still rules.

garethg, are you building a boat somewhere in the toronto area? I'd like to witness the progress.

One difference between sailing boats and any racing canoes , including DBs , is that sail boats never exceed hull speed (except cats or while surfing down waves) so some extra resistance at hull speed will not slow the boat down because there is prabably more power than required. Racing canoes are generally exceeding hull speed so extra resistance will make a difference , even a small difference counts when races are won by tenths of a second. Besides , as mentioned above , how much water can be drained in the short race.

Sailboats do exceed hull speed in certain conditions beyond surfing down a wave. International 14's are the best example. It is common to plane upwind in a 14 therefore exceeding hull speed. Any planing hull, upwind or downwind is exceeding hull speed. In a short DB race, some water will drain which is better than no water draining and the potential increase of water due to splashing. Bailers are worth a try. If they do not work, take them out and fill the holes. The notion of at least experimenting is fantastic.

You people are obviously not familiar enough with these bailers to propose them for use in a dragon boat race.

When the boat is not moving or not moving fast enough for the suction to take place, the water actually comes INTO the boat through the bailer openings.
Can you imagine sitting at the starting line waiting for the gun with water gushing into the boat or the alternate scenario where a paddler has to reach down after the gun goes to open the bailer. It is not practical.

Yes and no. You are right to say at the start you do not want them open. Agreed for sure. However, once moving they could be very effective. The real challenge is to ensure the person sitting in the seat that has the bailer can operate it with the his or her foot and knows what they are doing. Some will say this is not possible while in stroke however it is. They make a lot of sense and are definalty worth trying. The key is the hull must be moving through the water for them to create suction and not in turn fill the boat. Give it a go. Let's see how they work. I think they would be an excllent additio to the boats. Another great develoepemtn would be a pure carbon hull. It is time to get these boats down to few hundred pounds and see what they can really do.

Thanks to everyone for their comments, and please keep them coming, especially regards buoyancy, and a central longitudinal tank (see original post), and whether this would be a help or a hindrance to paddlers.

Yes, I for one, am not fully familiar with bailers, hence my questions.
I find it hard to believe that water comes into the boat when the boat is still.
Is this really true?

Regardless of this, it seems there is no good reason not to at least offer these as an option.
For me, the main purpose is to make dragon boating safer.
Most of the time spent in the boat will be for training, so even if they are not used in races, they can make a big difference to the overall safety of the sport. Especially considering that it is during training when there is likely to be no safety boats around.

I am not building boats in Canada, but together with my partners, in China.
Sorry for not making this clear from the beginning, but I didn't want to use this forum to promote our boats.

For sure, the boats could be built with carbon, and save weight, but I think the increase in speed would be minimal, and the increase in cost would be huge.
If someone still wanted this, we could look into it, at least.

Regards
Gareth

"Yes, I for one, am not fully familiar with bailers, hence my questions.
I find it hard to believe that water comes into the boat when the boat is still.
Is this really true?"

Yes for nearly all boats - except very light extreamly boyant ones (for example sea kayaks at resorts have holes for the waves to escape when they wash in).

Personally I can't imagine how putting boyancy in a Dragon Boat would make it any safer. Accidents are more likely the result of people who can't swim well not wearing life jackets than any other real safety issue.

Despite assurances from importers China boats continue to have a bad rep for quality and durability. The problem seems inherant with anything coming out of China these days. What makes this boat any different?

Sorry to chime in late, this may have been covered by I'm too lazy to read all the other messages.

I have seem many more dragon boats tip over than sink. But if they do sink, it's usually to just below the surface of the water, not down to the bottom.

I think increased buoyancy could cause a problem by making the boat "tippier". The BUK's are a good example of this. Higher riding, much more buoyant that the soggy old teak boats of the past. But buy being more buoyant and riding higher in the water they tip more, which is dangerous.

The old boats could occasionally "submarine", where a leak up front (or loading the boat bow-heavy) could cause the boat to gracefully submerge itself, all the while filled with chuckling paddlers as they go waist deap into the water.

On the other hand, the BUK's tend to rock, then tip, spilling paddlers into the water in a much more violent fashion.

Okay, end of essay. Take it for what it's worth.

That is a really good point.

The old teak boats where very difficult to tip and thus "safe" (though tipping isn't the real safety issue). As boats have gotten narrower and more boyant (i.e. faster), they have become tippier.

Hard to get around this unless you want to design it after the Dragon Huki!