water ballast sailboats

Yachting World

• Digital Edition

Pip Hare’s sailing masterclass: How to make the most of a water ballast system

• May 21, 2020

Water ballast is no longer the preserve of ocean racing yachts, it can now be found on performance cruisers and smaller racing boats. Pip Hare shares her top tips for using it

The JPK 1030 features transfer pipe and inspection hatches. Photo: Jean-Marie Lio

No two water ballast systems seem to be the same, but the principles for use and troubleshooting remain the same. Here are some guidelines for success.

Filling ballast

The ballast is filled via a scoop in the bottom of the boat, which is like a ‘reverse snorkel’. The snorkel is pushed down with the hole forward to fill the ballast, when the hole is facing aft the tanks can empty. To seal the system the scoop is retracted into the hull, leaving a flush finish.

A single scoop will be situated on the centreline, while twin scoops are placed outboard, so the leeward scoop must always be used for filling. When the scoop is pushed down, providing water is moving over the hull it will start to fire water into the boat. Filling can be achieved through continued forwards motion although this can take a lot of time so a pump is often used to accelerate the process.

Before pushing down the scoop, ensure all valves are in the correct position – this takes concentration if you’re not familiar with the system. Check:

• Valve to leeward scoop is open.
• Valves to leeward tanks are shut.
• Valves to water pump is open.
• Valves out of water pump are either directing towards windward tanks, or open on windward and closed on the leeward side.
• Correct windward tanks are selected – you can fill multiple tanks at the same time.

Once the valves are in the correct position push the scoop down then turn on the ballast pump. Once water is overflowing from the breathers on deck, first close the tank valves, then shut off the pump and retract the scoop.

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If you’ve been running the ballast pump but the tanks are not filling then look for air in the system. Airlocks are a common problem with a pump and can be tricky to remove. Start by identifying where the lock is; transparent pipes are helpful. Then your objective is to flood that part of the pipe.

Every system will be different but things that can work include turning off the pump, rotating the scoop aft to empty for a few seconds, then face it forward and turn on the pump again. Or try changing the angle of heel to flatten the boat momentarily.

If all else fails, changing tack but leaving whatever ballast you have on the same side might shift the air. Tack, then tack back and try the whole process again.

Transferring ballast

Any manoeuvre involving transferring ballast is going to take time and it’s important to factor this into your planning and make sure you have enough ‘runway’ to complete your manoeuvre. For example, if you know it takes 140 seconds to drop the ballast and you’re sailing upwind at eight knots you’ll need one third of a mile to complete the tack from the moment you open the valves.

Use the time it takes for the ballast to transfer to get set up on deck for tacking and to move the stack to leeward (if allowed). Remember the trim of the boat will change while the ballast drops, so ease the mainsheet or traveller to control excess heel and feather the boat into gusts.

The process for transferring ballast is simple:

• Check scoops are retracted and valves closed.
• Open leeward tank valves, open transfer valves, open windward tank valves.
• Once all water has transferred, close all valves.

The most common mistake is to close the valves and tack before all the water has run down. Sight glasses can help but they often don’t go to the bottom of the tank. Try putting your ear close to the windward transfer pipe, you should be able to hear water running through; if there’s no sound then the tank is empty. Water will rush out of the deck breathers on the leeward side but this may happen before the windward side is empty.

Always check the leeward side after a manoeuvre and empty out any water that’s left. Expect to top up the windward side over time.

Deck-mounted control rods can open or close the ballast transfer valves. Photo: Jean-Marie Liot

Dropping the ballast

There are no tricks to emptying the ballast, other than adding a little extra heel towards the end of the process. The routine is:

• Push the leeward scoop down and turn it to face aft.
• Double check leeward tank valves are closed.
• Select the tank you wish to empty and open all valves between that tank and the scoop.
• When finished close the valves and retract the scoop.

Management and maintenance tips

• Put luminous tape on the scoops so you can easily see which way they’re facing in the dark.
• Check inspection hatches and seals regularly. These hatches are a constant pain and expect them to leak. If going on a longer voyage, then take plenty of spare hatch seals and a couple of spare hatches.
• Try very hard not to step on ballast pipes or valves.
• Check both tank levels regularly. It’s not uncommon to lose water from the windward tank or for the leeward tank to start to fill over time.
• Check all valves, particularly gate valves, are closing fully and also check the leeward deck breathers are not letting water into the tanks – which can happen if sailing with the rail constantly underwater or if the breathers are damaged.

First published in the May 2020 edition of Yachting World.

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• Water Ballast System

Why a Water Ballast System is Worth Thinking About

A water ballast system in a cruising boat? Not a concept the traditionalists are likely to accept unreservedly. But providing the boat isn't dependent on this for stability it can be very beneficial in a seaway.

Such a water ballast system was part of the design philosophy when we built our cruising boat Alacazam , where it just supplements the permanent ballast in the keel bulb providing additional weight to windward when required.

The water is carried in two tanks on each side at the extremity of the waterline beam, each capable of being independently filled and drained by two 12v electric pumps. This is well below the point of maximum beam, but provides substantial benefits.

The Benefits of a Water Ballast System

• the boat's Centre of Gravity is no longer on the centreline, but is transferred outboard;
• as the boat heels, the righting moment increases due to the extended horizontal distance between the centre of buoyancy of the hull, and the centre of gravity of the water ballast;
• the Roll Moment of Inertia is significantly increased in terms of both pitch and roll;
• if caught with the water ballast on the wrong tack, the converse of the above applies such that the heel to leeward is not dramatically affected.

Freshwater or Seawater Water Ballast?

Initially the cruising man in me was reluctant to forego the increased freshwater capacity that the ballast tanks could provide, so they were used to supplement the standard water tanks located close to, and either side of, the centreline.

However, after lugging over 1,000lbs of this additional water all the way across the Atlantic without using any of it, I converted it to a seawater system.

Now I can get rid of it and replace it as required, and think of it as adjustable displacement . Tacking is done by opening a couple of simple valves and switching on the appropriate transfer pump. The boat's then tacked in the normal way, and then when the transfer is complete, the valves are closed and the pump's switched off.

Hard on the wind, with both windward tanks full, Alacazam heels about 6 degrees less for the same sail area and wind strength than she otherwise would, and sails quicker as a consequence. The concentration of outboard weight in the centre section of the boat noticeably improves the fore-and-aft stability, and coupled with less heel, reduces pitch and roll appreciably, the increased displacement making the boat generally more comfortable.

As the wind moves aft, the forward tank is drained and when well off the wind both tanks are drained. Of course in a short-tacking situation, the valve turning and pump switching involved in swapping the water from one side to the other requires a lot more rushing about that I'm accustomed to, so we only use the water ballast system on long offshore tacks.

The downside is that the tanks and the plumbing take up space that could otherwise be used for stowage, but there's no doubt that a moderate degree of water ballast in a light-ish displacement cruising yacht can improve both her performance and crew comfort.

Water Ballast: A Few FAQs...

What is a water ballast system?

A water ballast system is a device that allows a sailboat to fill or empty tanks with seawater to adjust its stability, trim, and performance. The water ballast can be transferred from one side of the boat to the other, or from the bow to the stern, depending on the sailing conditions.

How does a water ballast system work?

A water ballast system works by using scoops, valves, pumps, and tanks to control the flow of water in and out of the boat. The scoops are openings in the hull that can be lowered or raised to capture or release water. The valves are switches that direct the water to the desired tanks. The pumps are devices that speed up the filling or emptying process. The tanks are containers that store the water ballast.

What are the benefits of a water ballast system?

A water ballast system can provide several benefits for a sailboat, such as:

• Increasing stability by lowering the centre of gravity and reducing the angle of heel;
• Improving performance by optimizing the sail area and reducing the wetted surface;
• Enhancing comfort by smoothing the motion and reducing the rolling;
• Saving space and cost by eliminating the need for fixed ballast.

What are the drawbacks of a water ballast system?

A water ballast system can also have some drawbacks for a sailboat, such as:

• Taking up precious room on board that could be used for storage or accommodation;
• Increasing complexity and maintenance costs due to the additional equipment and plumbing;
• Creating potential environmental issues by spreading invasive species or pollutants through the water exchange;
• Losing effectiveness at low speeds or when sailing upwind due to the reduced water pressure on the scoops.

How much water ballast do I need for my sailboat?

The amount of water ballast needed for a sailboat depends on several factors, such as the size, shape, and design of the hull, the weight and distribution of the fixed ballast, the rig and sail plan, and the sailing conditions. There is no simple formula to calculate the optimal water ballast, but some general guidelines are:

• The water ballast should be between 10% and 30% of the total displacement of the boat;
• The water ballast should be placed as low and as far outboard as possible to maximize its righting moment;
• The water ballast should be adjusted according to the wind strength, wave height, and point of sail to achieve the best balance and trim.

The above answers were drafted by sailboat-cruising.com using GPT-4 (OpenAI’s large-scale language-generation model) as a research assistant to develop source material; to the best of our knowledge,  we believe them to be accurate.

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What Is A Water Ballast Sailboat?

On my own sailboat, I have a water ballast system. I was unsure about the stability and efficacy of this system at first. From my experience, a water ballast sailboat, in place of a lead keel boat, is an incredibly worthwhile and effective option to consider when purchasing a sailboat.

What is a water ballast sailboat? A water ballast sailboat has a water reservoir on board instead of a lead keel. Water is taken on board and fills the bottom 25% of the hull. The water in the ballast tanks acts as a counter weight to prevent the wind from blowing the boat over in strong wind.

A water ballast sailboats does have some impressive upsides, but there are some concessions you need to make if you are considering purchasing or chartering this design of sailboat. Below are some important details of both a water ballast system and how they compare to a standard lead weighted keel.

How a Water Ballast System Works

The source for stability on a water ballasted sailboat is the weight of the water in the tanks. The water ballast keeps the boat from rocking back and forth much in the same way a lead keel boat does. If the energy input is sufficient, the boat will roll one way, then the other in both systems. Water ballast stability does not refer to total stability. All sailboats heel over.

Keep in mind these two key principles. The water in the ballast tank takes on the shape of the hull and the floor of the cabin above it. As a general rule, water will always find true level.

When the boat lists or heels over, the water line lifts up and out of the water on one side. The water line on the other side then dips below the surface. As the boat rolls to one side, the water in the ballast tanks is lifted out of the water for a brief moment. Gravity then kicks in and pulls the ballast tank water back to level.

Water Ballast Tanks In Action During Sailing

In keeping with the principles above, when wind pushes on the sails, the boat will tend to lean over. The water in the ballast tanks will be raised up out of the surrounding water as the boat heels over. The further the boat is pushed over by the wind, the more ballast water is being raised above the water the boat is sailing in.

The weight of the water ballast multiplies as the boat is pushed further and further over, until a balance is achieved between the wind force and the gravity pulling level on the ballast tanks. With practice, you can find this balance and maintain it based almost entirely on the amount of sail you have flying at the time.

With the practical application of water ballast systems explained, let’s get into some of the functions of properly and safely working one of these systems.

What Exactly Are Water Ballast Tanks?

Water ballast tanks are large water compartments designed to take in the water that the boat is floating in. They are located under the floor of the cabin of the sailboat. Water ballast tanks typically run most of the length and width of the sailboat. From outside the sailboat, the hull area from the waterline and down is almost completely filled with water. The ballast tanks are manually filled once the boat is placed in the water.

How Are The Ballast Tanks Filled?

There are two key components to a water ballast system on a sailboat. The plug and the vent . The design and innovation on how they are filled and emptied may differ from one brand of boat to another, but the principles are all the same.

The first component is the plug . This is usually located at the lowest point of the sailboat under the water line. This plug opens and closes and allows water to flood and drain the ballast tanks. This plug is opened and closed from inside the cabin of the sailboat using a long rod.

This rod reaches vertically from the plug to the floor of the cabin. It operates the plug, allowing it to be pushed down and away from the hull to open. When the tanks are full, the rod is pulled up, which seals the plug inside or up against the hull, and closes off further water flow.

There is also a vent located beside the plug rod that must be opened while flooding the tanks. This must be open in order for the displaced air to escape as the water in the ballast rises. Once the tanks are full, the plug needs to be closed (rod pulled up) and the vent sealed off in order for the ballast water to keep from entering in the sailboat cabin.

What If the Ballast Tanks Remain Empty?

Empty ballast tanks can be a real hazard on a water ballast sailboat. This may be a point of contention when considering the purchase of this kind of sailboat. Imagine if you will what would happen to an inflated balloon if you glued a roll of dimes on it and set it afloat. Gravity would obviously take hold of the weight and pull the balloon over.

The same principle is at work on a water ballast sailboat, but not necessarily to the same extreme. I have seen capsize reports on the news where too many people were on the deck of an empty water ballast sailboat, and it turned over.

Now, capsizing is not always the case. In situations like the one above, the capsized vessel was overloaded along with having empty ballast tanks. Other factors could also contribute such as being oversailed and in rough water conditions.

In normal sailing situations capsizing would not normally happen. For example, a small family out for an afternoon could board a water ballast sailboat, and forget to fill the ballast tanks.

What they would immediately notice is the sailboat constantly rolling from side to side at the smallest wave, or the slightest movement of people around the boat. Anyone aboard would know something was not right and take stock of the situation and remedy it. Keeping your balance on an empty-ballast-tank boat is no easy task.

Filling and draining ballast tanks is all a part of owning or operating a water ballast sailboat. Hazardous situations arise due to fairly extreme negligence, but they still can happen.

Benefits of a Water Ballast System

Water ballast boats have some unique advantages. If hitting bottom or shallow water sailing is in your future, you would certainly benefit from a water ballast boat.

Fixed keel boats with a lead keel usually have a fairly deep draft in comparison to water ballast boats. Water ballasted boats can get away with a center board, a dagger board or a swing keel since the stability is governed by the water weight and not the keel weight.

This means you have an abundance of anchoring options not available to the majority of sailboats. On top of that, having easy access to shore means I can have a campfire, set up tents and chairs on shore, let the kids run wild until bedtime, and the boat is just a few steps away.

On my own Macgregor 26D, I only need 15 inches of water once the centerboard and rudder are pulled up. This means I can be in very close proximity to shore while at anchor. I have had several tenders from other boats approach me to help while at anchor, because I appear to have run aground. When I explain the water ballast system to them, they smack their head and have a laugh and head on back. It’s really quite amusing.

Drawbacks to a Water Ballast Sailboat

In all honesty, the worst part of a water ballast sailboat is the amount of space the ballast tanks take up overall. In a keel boat, the weight is condensed by the weight of the lead. The floor of the boat can be lower, making for a great deal more headroom than a water ballast sailboat.

Water needs more space for the same weight as lead, and therefore the floor is much “higher” in the cabin of my boat than on a lead keel boat. I can not stand up in the cabin of my boat. I’m 6’2″. There are not a lot of boats under 30ft that I can stand all the way up in, so that’s how I rationalize the discomfort of my boat. First world problems, I know.

Related Questions

Where can/should i dump my water ballast tanks.

There are actually laws that prohibit the dumping of balast tanks in some areas. These laws pertain to vessels that come from remote or foreign parts of the world where ecosystems are very different. Sometimes ballast tanks draw in organisms and planlife that can turn into invasive and unwanted species in a foreign port.

Dumping ballast tanks should always be done at least 10 miles offshore before approaching a foreign port. If you can only dump your ballast tanks once the boat is out of the water, please ensure to do it when you are well inland to prevent the spread of invasive species.

Will the sailboat sink if I forget to close the plug and vent?

This actually happened to me, so I thought I’d share. My 1989 Macgregor 26D did not sink when I forgot to close the ballast plug and vent. I can only attribute it to a safety feature built right into the design of the boat. I don’t really know. All I know is I was distracted by a busy boatlaunch, a motor that didn’t want to start, and a mess of kids bounding around all over the boat. By the time I remembered I nearly had a heart attack. I jumped down the stairs and looked at the ballast vent, and it had stopped filling on its own. I closed everything up and had a great day!

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The Physics of Water Ballast

Nick Newland recently wrote an informative article on water ballast for Water Craft magazine (Newland 2015).  Following a discussion on the Swallow Yachts Association Forum, this article aims to explain the physics behind the use of water ballast.

Water ballast is… ballast!

So water ballast works like any other ballast – end of story!   But there are differences.  The lead could have been put in a smaller box so it would take up less space in the boat and be positioned lower.  With water, the box will take up more space in the hull and probably will be higher in the boat.

On the other hand, if the wind drops and you don’t need ballast,  with lead you are stuck with it.  With water you can get rid of it and,  if you then change your mind you can refill the box from the river or sea.  And, you don’t have to take all that weight of water home on the trailer!

This ability to sail a water ballasted boat with tanks either empty or full, depending on the conditions,  means it’s worth considering in greater detail the effect ballast has both on boat stability and handling characteristics.

Mass, weight, and buoyancy

A boat like any other object is made up of various bits of material – wood, GRP, etc. which all added together make up the mass of the boat.  The mass of the boat is a physical characteristic which only changes if you add a new gadget, or more ballast, or you break a bit off!

Before putting your boat in the water, if you hang it from a spring balance you would measure its weight .  Weight is the force of gravity pulling the boat down.  It is proportional to the boat’s mass, and it acts through the centre of that mass,  which is called the centre of gravity ( CoG ).  Here on earth, spring balances are calibrated so that the weight is numerically equal to the mass.  On the moon your boat would have the same mass as on earth but would weigh less, because gravity is less.

As you lower your boat into the water it starts to be supported by the force of buoyancy.  The size of this buoyancy force depends on the amount of water displaced by the boat’s hull.  It acts through the centre of buoyancy ( CoB ) which is the centre of volume of the bit of the boat below the water surface. The boat will settle in the water until it is floating at a level where the buoyancy force exactly balances the weight of the boat.  So your spring balance now shows the apparent weight as zero even though the real weight of the boat has not changed, and of course, the boat still has the same mass.

How people think stability works – Deep keeled yachts

Many racing yachts have a very long fin keel with a big bulb of lead at the bottom.  For yachts like that the centre of gravity can be below the centre of buoyancy (figure 1).  Thus when the yacht heels, the force of gravity and the force of buoyancy act to rotate the boat back towards an upright position.

A longer the keel will give a bigger offset between the CoG and the CoB when the yacht heels, and hence a larger the rotational force bringing the yacht upright.  Also a heavier keel will increase both the weight of the yacht and the  balancing buoyancy force, again resulting in a larger righting moment.

This “yotties “ view of the world,  is NOT how most boats and ships work!  However it is how many people tend to think of stability.  When they look at a large cruise ship with many decks above the waterline and wonder how it stays upright, they are unconsciously assuming that the CoG must be below the CoB to create stability.

How stability usually works – Most Boats and ships

Most boats and ships don’t have a deep keel and the ballast or cargo is carried within the main part of the hull.  In this case, the centre of gravity, CoG, is higher than the centre of buoyancy, CoB.

Figure 4a illustrates what happens when the ship or boat heels. Lets assume the view is from astern so the boat heels to starboard.  The effect is to move the CoG to starboard and slightly downwards.  However the CoB is moved further still in a starboard direction.  As a result the weight and the buoyancy form a force couple which tends to rotate the boat back into an upright position.

Figure 4b illustrates the effect of adding a full ballast tank.  When the boat is upright it is lower in the water and the CoG is closer to the waterline. As a result, when the boat heels the CoG does not move as far to starboard as when the boat is empty whereas the CoB moves slightly further.  This increases the stability compared to the unballasted boat.

However the main effect of filling the ballast tank is to increase the boat’s weight.  As discussed above, the boats sinks downwards until the opposing buoyancy force is also increased by the same amount.  The two forces tending to rotate the boat upright  are therefore, not only spaced further apart, but also much larger.  Thus the boat is more stable with a full ballast tank.

That the effect of increased boat weight is important is easy to imagine if you think of trying to tilt a box placed on the ground.  If the box is empty it is relatively easy.  If the box is full of water it will be much harder to tilt.

Note the increased stability does not require the water ballast to be raised above the water surface, as sometimes believed.  As long as the CoB moves out more than the CoG the boat will remain stable, and the heavier the full ballast tank, the more the stability.

The “gz curve” – righting lever values

To indicate the stability of a boat, yachting magazines publish a “gz curve”.  “gz” is  simply the horizontal separation of the forces of gravity and buoyancy – what we have just been discussing.  It should really be called the righting arm or lever.  Figure 6  illustrates how the term “gz” seems to have arisen and shows as an example of a curve (the BC20 with full ballast tanks).  For this example the gz value remains positive until about 132° of heel which indicates that the boat would self-right from a knock down condition.

For most boats there is one, characteristic gz curve.  But for a water ballasted boat that can be sailed with or without ballast,  the large changes in the overall weight and it’s distribution within the boat result in two distinct gz curves.  These are shown in figure 7 for four Swallow Boats using data published in Practical Boat Owner (Harding, 2009, 2010, 2011, 2013).

Figure 7 Righting Lever or “gz” curves for various Swallow Boats as published in Practical Boat Owner reviews.

Unfortunately,  curves for gz for the ballasted and un-ballasted cases (as in Figure 7) don’t fully represent the effect of ballast on stability because they neglect the change in boat weight.  In his article on water ballast,  Nick Newland (2015) states that for a Bay Raider, the water ballast increases gz by about 30% but more than doubles the righting moment. ( In fact, for the BR20 Figure 7 suggests that the difference is much more than that.  However it is possible that the unballasted curve published in PBO is wrong.  It implies that the BR20 is less stable than the BRe which, being more or less a BR20 with a cabin, should be the less stable.)

Comparing the change in stability – the “Righting Moment”

The actual righting force (the “ righting moment ” ) is given by:

(righting moment, rm) = (righting lever, gz) x (weight of boat)

Unfortunately,  righting moment values for different boats are difficult to compare because the boat weights are different.  Therefore Figure 8 demonstrates the increase in stability caused by the weight of the water ballast by plotting an “adjusted righting lever” defined by:

(adjusted gz) = ((righting lever gz) x (weight of boat +ballast + equipment)) (weight of bare boat)

Thus, if the boat has no ballast or equipment, the “adjusted gz” is the same as the gz value plotted in Figure 7.  The equipment weight (“ load ” =  weight of outboard, cooking gear, battery, etc.) has been added so as not to exaggerate the fractional effect of the water ballast weight by comparing to an empty hull.  The nominal values used for each boat are shown in the figure.  One should also add in the weight of crew but, since people move around and may even hike out, the crews effect on stability is hard to define and has not been included.

Figure 8 “Adjusted righting lever” values (see text) showing the relative difference in stability between having empty ballast tanks (red) and full tanks (blue). The grey lines are the unadjusted “gz” values as shown in Figure 7.

For the unballasted case the small increased magnitude of the adjusted value (red line) compared to the original gz value (grey) is due to the nominal “load” value assumed.  When the ballast tanks are filled with water, there is a small increase in stability due to the change in the righting lever length (upper grey line) but the actual change in stability is much larger (blue line) because of the weight of the ballast.

Stability near capsize

Figures 7 and 8 show that for each of the boats the maximum stability occurs at around 40° of heel. With greater heel the stability decreases with the unballasted curves showing zero or even negative stability when the boat is on its side at 90°.  If the position of added equipment such as the outboard were taken into account,  the curves suggest that, unballasted, each of these boats would tend to turn turtle. However beyond 90° the curves become positive and for the BR20, BRe, and BC20, the PBO reviews suggest that this is because of immersion of the hollow masts.  For the BC23, immersion of the coachroof is suggested. Whatever the cause , this positive stability peak might be enough to keep the boat floating on it’s side rather than turning to 180°.

The situation is much better if the boat is sailed with the water ballast tanks full. In that case all the boats show self-righting ability from a 90° knock down, although the Bay Cruisers, with their smaller cockpits have a greater margin of safety.

Figure 9 The yellow shading indicates the amount of the aft section of a Bay Cruiser 20 hull occupied by the buoyancy tanks needed for self-righting.

Nick Newland (2015) notes that with water ballast this self-righting ability comes at the cost of sacrificing part of the hull space near the gunwale to provide the correct buoyancy distribution.  For example the BC20 has large full depth buoyancy tanks at each quarter and across the stern.  The hull space lost to tanks for ballast and for buoyancy would seem to be the main disadvantage of using water as ballast.

Dynamic stability

So far the discussion of stability factors has not taken into account the effects of motion.

An oft quoted stability parameter, the “ metacentric height ” is related to the positions of the centre of gravity and centre of buoyancy, as discussed above. It is of relevance to ships and motor boats since it is related to the period of roll – the time taken to roll one way and back the other, in other words how fast the boats rocking motion is.  It is much less relevant for sailing boats because of the aerodynamic forces of the sails and the inertial effect of the mast.  More important are factors such as momentum and moment of inertia .

Both the momentum (mass  x velocity), and the force needed to accelerate the boat, are proportional to the boat’s mass.  Adding water ballast increases the boats mass by exactly the same amount as a similar weight of any other type of ballast.  If the ballast tank is full, that extra mass is exists whether the boat is on its trailer or in the water.

“ Moment of inertia ” is a measure of how difficult it is to rotate an object around a given axis (Figure 10).  Where the water ballast is contained in tanks fore and aft, as in the Bay Cruiser, filling the tanks makes the boat more similar to the dumbbell shaped object.  The axes for which moment of inertia is increased are those for yaw and pitch.  The roll axis is not significantly affected.

Is the boat faster with ballast tanks full or empty?

Obviously there is no one answer; whether you decide to sail with ballast tanks full of empty will depends on circumstances.  If you are out for a day’s sail in your Bay Raider you might have the tanks empty and enjoy planing past another boat which is carrying the equipment needed for a few days cruising.  But the cruising owner the security of having a self righting boat might well be the decisive factor in keeping the tanks full.

At least with a water ballasted boat you have the choice and, hopefully the above discussion will help in weighing up the factors.  For example, consider beating into a choppy wind sea.  Having full tanks will do more than increase stability and allow the boat to sail more upright.  The extra momentum (from the increased mass) will mean that the boat is slowed down less by oncoming waves.  The increased moment of inertia will make the boat less “twitchy” so it is less deflected from the desired course.  You can use the Tiller Tamer and make a cup of coffee!

If you empty the ballast tanks, the boat will be significantly less stable, heeling more and forcing you to spill wind or feather windward.  With less mass the boat will be slowed more by slamming into waves.  On the other hand, if slowed up by a wave it will then accelerate faster.  The lower moment of inertia along the yaw axis will allow the boat to be quicker in responding to the helm.  Rather than cut through the waves, you may be able to thread a course between them or (with less inertia to pitching) ride over them.  Actively helming the boat dinghy fashion, you might be able to work  up higher to windward.  However you probably won’t have time to make coffee!

Water ballast gives you the choice and can vary that choice during the course of a day’s sailing.

Water ballast and safety

Finally, it is worth considering the safety factors inherent in a water ballasted boats. First, the ballast tanks create a double skinned hull over much of the boats underwater area. Puncturing a ballast tank will not sink the boat!  Second, consider those two crates illustrated in figure 1.  If placed in water the wooden crate full of water would float with it’s lid more or less awash.  Since the crate containing lead is the same size and weight, it would float in a similar fashion.

Figure 11 – The crate containing water doesn’t sink when holed.

Now imagine what will happen if you make a hole in the two crates (figure 11).  It won’t make much difference to the crate contain water; it will continue to float more or less at the surface.  On the other hand, the crate using lead for ballast will fill with water and sink!

Of course, people like me put heavy things like lead-acid batteries in their boats so even a wooden, water ballasted boat could sink if holed.  However it only needs some relatively small sealed buoyancy chambers (as built into Swallow Yachts) to ensure that a water ballasted boat will float even if holed.

(Peter Taylor, February 2015, revised October 2015)

Harding, David (2009) A different sort of dayboat (review of BR20) , Practical Boat Owner 506, February 2009, 44 – 47.

Harding, David  (2010) High-tech tradition (review of BC20) , Practical Boat Owner 526, September 2010, 39 – 42.

Harding, David  (2011) Technology meets tradition: Baycruiser 23 (review of BC23), Practical Boat Owner 539, September 2011, 40 – 43.

Harding, David  (2013) The super-simple trailer-sailer (review of BRe) , Practical Boat Owner 556, January 2013, 76 – 79.

Newland, Nick (2015) What’s the Point of Water Ballast? , Water Craft no. 109, Jan/Feb 2015, 30 – 33

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MODERN SAILBOAT DESIGN: Ballast Stability

At the end of our last discussion on stability we mentioned the old mono v. multihull worst-case-scenario debate re sinking to the bottom (monohull) versus capsizing on the surface (multihull). This time we’ll focus on that which drags the poor monohull to the bottom, which is, of course, its ballast. Ballast, ironically, is added to a boat to help it stay upright. As with form stability, the principle is obvious: an object is harder to up-end if a heavy weight is placed at the bottom of it. Witness the iconic inflatable punching clown. With the majority of its weight concentrated at floor level, the clown pops back upright every time you knock it down. This, of course, is exactly what you want your sailboat to do.

 Besides helping boats sink, ballast is counterproductive in another way: it makes a boat heavier and increases displacement , thus increasing resistance and decreasing speed. But this sad fact can be mitigated. The amount of ballast needed to counteract the capsizing forces of wind and wave decreases dramatically the lower it is placed in the boat. Unlike the clown, which must always have its feet on the ground, the bottom of a sailboat can reach as far down as there is water for it to float in. This is one reason why racing sailors always prefer very deep keels and why gunkholing cruisers must agonize over the question of draft. On a stock 40-foot boat, for example, the weight differential between a shoal-draft cruising keel and a deep racing keel installed on otherwise identical hulls can amount to 20% or more of the boat’s total displacement. For many, this will seem a heavy price to pay (pun intended) for shoal-draft capability.

Just as weight down low increases stability, weight up high–generally speaking, just about any weight added at or above deck level–decreases it. It is important, therefore, not to think of ballast as a discrete feature. Think instead of a boat’s total weight and how it is distributed. For example, adding one pound of weight at the masthead of a 35- to 40-foot cruising boat effectively subtracts 7 to 10 pounds of ballast from its keel. Conversely, subtracting that pound adds 7 to 10 pounds of ballast. The effects are less dramatic but are still significant when weight is redistributed closer to the boat’s center of gravity.

Aboard most cruising boats, the center of gravity is more or less about 6 inches above the waterline. Any weight subtracted above or added below this point increases the boat’s effective ballast and lowers its center of gravity. Such increases are multiplied according to the weight’s vertical distance from the center of gravity. For example, subtracting 1 pound of weight 35 feet above the center of gravity is equivalent to subtracting 35 pounds 1 foot above it. Adding 1 pound 7 feet below the center gravity is equivalent to adding 7 pounds 1 foot below it.

The bottom line (another intended pun) is that you should always strive to keep weight as low as possible, whether or not it is officially designated “ballast.” This is why racing sailors always embrace technology that dramatically reduces weight aloft, such as carbon-fiber spars and fiber rigging. It is also why cruising sailors should be more circumspect when adding weight to their rigs. Roller-furling headsails, in-mast furling mainsails, extra-heavy wire rigging, mast-mounted radomes, mast steps, and other such gear may improve a boat’s “cruise-ability,” but their cumulative weight also significantly decreases its stability.

Cruisers often store too much gear on deck, which raises a boat’s center of gravity and can make it considerably less stable

Boats that rely primarily on ballast for stability tend to be narrow and deep. In the past they also often had a great deal of deadrise in their hulls, though this is less true now. Narrow, heavily ballasted boats, particularly those with lots of deadrise, usually are tender and quickly heel to significant angles when pressed by even a moderate breeze. But this does not make them “unstable.” When pressed to extremes, they are usually more stable than stiffer boats that rely more on form stability to stay upright. Unlike form stability, which increases a boat’s initial stability, ballast stability increases what is known as ultimate or reserve stability, which is what helps a boat recover and roll upright again–just like the punching clown–after it has been knocked flat or even capsized.

Tender boats, like stiff boats, can be both comfortable and uncomfortable. Their tendency to heel easily often makes inexperienced crew feel nervous and uncomfortable, and even for experienced sailors, working at severe angles for extended periods of time can be taxing. But when the sea gets rough a tender boat normally has a smoother motion than a stiff one. It rolls to greater angles, but does so more slowly, without the vicious snapping and jerking that characterizes the motion of a stiff boat. Sailing to weather in a strong breeze a tender boat’s lee rail will be buried much of the time, and the crew on deck will get wet, but the boat will not pound as violently as a stiff boat.

For cruising sailors, the question of which sort of stability to favor when selecting a boat is a serious one. Many designs available today, of course, are relatively moderate and compromise between extremes. As a general rule, however, popular modern designs tend to be relatively light and wide with shallow bilges, and thus are more stiff than tender. Older designs from the CCA era are usually heavier, narrower, and more tender. As a general rule, coastal cruisers who expect to sail primarily in moderate conditions can, if they like, favor faster, more modern, stiffer designs. Bluewater cruisers who are more likely to encounter extreme conditions should consider whether they’d be better off in slower, more tender design with more ultimate stability.

Shifting Ballast

The most effective way to increase initial stability aboard a boat that may or may not have good form stability is to shift significant amounts of ballast to windward while sailing. This creates a lever arm that operates at a right angle to the sail plan, which increases the ballast’s effectiveness and allows a boat to carry significantly more sail.

Crews on modern planing skiffs like this 49er have to stay well outboard to keep their boats upright

This principle is seen at work on any unballasted sailing dinghy that depends primarily on crew weight to stay upright. To prevent the boat from toppling over to leeward, the crew hikes out on the windward rail. The further to windward they can get, the more sail the boat can carry, as the crew’s effective weight is increased by the longer lever arm. On modern dinghies you often see devices such as trapezes and/or hiking rails that allow crew to get as far outboard as possible. On traditional boats like Bahamian sloops and Chesapeake log canoes the crew sits out over the water on long planks that protrude from the windward rail. When the boat is tacked, the planks are moved from one side to the other, and there is a mad scramble as the crew repositions itself.

A traditional Chesapeake log canoe in action

These days ballast on larger boats can be shifted in more sophisticated ways. In one method known as water ballasting, large quantities of seawater are moved from one side of the boat to the other as it tacks. The water is shifted between dedicated tanks on the outboard edges of the hull’s interior either with a pump or by letting the water run downhill from the windward tank to the leeward tank before tacking. Water ballast augments a conventional ballast keel and is released overboard when it is not needed.

Another way to shift ballast is with a canting keel. These are struts with heavy ballast bulbs that can swing from a vertical position under a boat’s hull out to angles of up to 55 degrees. Large canting-keel monohulls 70 feet and longer have hit top speeds in excess of 30 knots, which is comparable to speeds routinely achieved by large racing catamarans. Several canting-keel boats have sailed 600 miles or more in open water in a single 24-hour period, maintaining average speeds of over 20 knots. What makes canting keels so powerful is that they shift all of a boat’s ballast to windward while keeping it well below the hull, thus greatly increasing its effectiveness. A keel capable of canting 55 degrees requires 25 to more than 60 percent less ballast than a fixed keel to support the same hull and sail plan. The result is a much lighter boat with a much higher SA/D ratio and a much lower D/L ratio.

A modern raceboat with its ballast keel canted to windward. The daggerboards rather than the keel create hydrodynamic lift

Canting keels do have their complications. When canted well to windward a keel ceases to function as a hydrodynamic foil and other foils must therefore take its place. These can be significantly smaller than the keel itself, due to the high speeds at which the boat travels. Often these auxiliary foils are daggerboards in the boat’s midsection, one on each side, with only the leeward board deployed at any given time. Or there may be a second rudder forward of the keel, often called a canard, that works in conjunction with the primary rudder to both resist leeway and steer the boat. This configuration, referred to as the Canting Ballast Twin Foil (CBTF) system , is a patented technology seen on large maxi yachts such as Roy Disney’s last Pyewacket . Centerboards and centerline daggerboards have also been used.

Another major complication is the mechanism that swings the keel back and forth. This mechanism is somewhat simpler on smaller boats, as the top of the keel, which protrudes several feet into the boat’s interior, can be pulled to either side with nothing more than a hefty tackle. On larger boats, however, the weight that must be shifted can be enormous and mechanical assistance is required. This is normally provided by large hydraulic rams and pumps powered by the boat’s main engine or a donkey engine, which must be running when the keel is moving. In all cases the pivoting keel joint in the bottom of the hull must be properly sealed and protected against flooding. Not surprisingly, dramatic failures are fairly routine.

Canting keels have also been installed on a few high-end custom performance cruisers. Examples include the Baltic 78, certain luxury performance cruisers built by Wally Yachts, and a sleek 65-foot one-off boat, Spirit of Adventure , designed by Owen Clarke Design of New Zealand for a private client. The canting keel on Spirit is also a lifting keel, as is the canting keel on the 100-foot super-maxi Maximus , a no-holds-barred racer launched back in 2005. It is unlikely however that canting keels, lifting or otherwise, will trickle down any further into the cruising-boat market. The systems are just too complex, too expensive, and potentially unreliable.

The keel on this custom cruiser, Spirit of Adventure , designed by Owen Clarke Design, both cants side-to-side and shifts up and down (Photo by Paul Todd)

Water-ballast systems, on the other hand, have proven more popular. Indeed, several small trailerable cruising boats use static water ballast as their primary ballast. On these boats the ballast tanks are low in the bilge on the boat’s centerline and are filled after the boat is launched to increase its displacement and stability. When the boat is hauled from the water, the ballast tank is emptied to reduce trailering weight. Since the ballast is never shifted, these are more appropriately termed static variable-ballast systems. Dynamic shifting-ballast systems are less common but have appeared on several performance cruising designs. These include at least one production boat, Hunter Marine’s old HC-50, which was designed to be sailed by a couple. On some other production performance cruisers it is also possible to shift water stored in the freshwater tanks from one side of the boat to the other.

Like canting keels, water-ballast systems make a boat much more complex. The ballast tanks take up interior space that could otherwise be devoted to accommodations, and they require a great deal of extra plumbing for picking up and discharging raw water and for moving it from tank to tank. Because water is not particularly dense, because ballast tanks must be located inside rather than below the main hull, and because the water ballast represents only a portion of the boat’s total ballast, water-ballast systems also do not have nearly as dramatic an effect upon performance as do canting keels.

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These are useful advice. Thanks! For quality and affordable boat ballast check out http://www.waterskiersworld.com/category-list/accessories/boat-ballast-fat-sacs-pumps.html

Found this looking for research on a short high-school presentation on how boats work. Made my head hurt with funky words. 10/10

Very helpful in analyzing where to put 500 pounds of batteries for a conversion from diesel to electronic propulsion.

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  All About Water Ballast Systems Advantages of Existing Internal Water Ballast Systems How Water Ballast Increases Boat Speed and Comfort Advantages of New External Water Ballast System Stability and What Hangs In The Balance

Advantages of Existing Internal Water Ballast Systems

M any new high performance racing and cruising sailboats are being manufactured with built-in rigid internal water ballast tanks to improve their upwind performance, without sacrificing downwind performance.  This is accomplished by filling the windward ballast tank with water while going upwind to stabilize the sailboat, and emptying the ballast when going downwind for less weight.  Reducing the angle of heel not only increases performance but also increases comfort and safety similar to sailing down wind.  The cockpit is much more comfortable and you have a safer working platform, especially on the fore deck.  Below deck tasks such as cooking, using the head or sleeping (in improper sea berths) are made safer and easier in heavy seas.  Even when just day sailing with friends and family it becomes more comfortable -- everyone likes a nearly level boat!  Reefing is also minimized by stabilizing the boat in moderate conditions and not having to depower the sails.

Examples of  internal water ballast manufactured into high performance cruising sailboats can be found in Roger Martin's 40 foot Gray Wolf, with the following advantages:

" with winds westerly at 15 to 18 knots.  Our initial angle of heel, close reaching with full main and 120 percent jib, was near 10 degrees.  This all but disappeared after Rodger scurried below and switched on a Rule 3600 pump to fill the windward ballast tank.  Our speed subsequently increased by a knot, to say nothing of our comfort level."  "Each port and starboard tank holds 262 gallons (2,240 pounds). "       CRUISING WORLD magazine June 1997, page 91.

and also, in Steve Dashew's 80 foot Beowulf:

"Beowulf's 7,500 pounds of saltwater ballast, stored in side tanks, reduces heeling by 8 degrees and adds several knots to boat speed".     CRUISING WORLD magazine August 1998, page 36.

How Water Ballast Increases Boat Speed and Comfort Water ballast works by reducing the angle of heel on a sailboat.  This makes the keel, rudder and sails increase their projected profile and lift in the horizontal direction (less downward sail pressure), generating greater driving and tracking forces that make the sailboat go faster.  It also reduces leeway (side slipping) and the resulting (hull form) drag.  Although there is additional drag from the hull with the added ballast weight, it is minimal when compared to the gain (also in water line length).

Modern sailboats that are light and have flat under bodies gain the most performance from water ballast since they are capable of going beyond their normal hull speed when planing.  Speeds beyond hull speed are generally achieved going down wind in brisk conditions having a good driving force, when the sailboat's bottom sections are kept flat on the water for planing.  The driving forces on a reach or upwind are not as direct, making the sailboat heel, no longer presenting the flat bottom sections of the vessel.  Adding water ballast on the windward beam while on a reach reduces the heeling angle, which again presents a flatter bottom for planing and increases the driving forces which make the sailboat go faster.  Heavy displacement sailboats have a substantial gain in performance with water ballasting, although they are limited by their hull speed. Light modern cruising sailboats also tend to have a harsh motion in heavy seas.  This can make it uncomfortable and difficult to perform normal tasks on ocean passages, with excessive heeling only aggravating the situation.  By adding additional water ballast weight on the windward beam, rolling and tossing are dampened and more velocity is sustained through oncoming waves.  With slower and less internal movement, as well as angle of heel, one has a more comfortable and safer sea kindly ride in heavy seas, with less time spent at sea with the added speed.  Also, water ballast can be placed on both sides of the sailboat to reduce rolling at anchorage or on one side to remove the vessel from a grounding. Advantages of New External Water Ballast System The new external water ballast system attaches to most sailboats in seconds without alterations, and can be moved from one rail to another or from one similar size boat to another.  This system provides all the advantages of internal water ballast for any existing sailboat.  Attempting to add  internal water ballast tanks to an existing boat would require major reconstruction and take up valuable internal space, even when not in use.  External water ballast also provides better performance with the ballast held further outward which has a greater stabilizing force for the same quantity of water.  External water ballast requires no active pumping for the emergency release of water on the leeward side of the boat and is also compliant with the 10 degree (heel) static rule for offshore safety (both sides 2x10°=20°). Disney's water ballast bags. Disney's water ballast bags, Sailing World. Home page for Maxi Marine external water ballast system.

As mentioned earlier, reaching speed is directly related to the heeling angle of a sailboat.  Some expensive high-tech solutions involve lightening the sail rig by the use of  Kevlar ® sails and carbon fiber masts, or use of bulbed keels to lower the center of gravity.  To measure the effect of  weight loss from the rig, project the center of the weight loss straight down from it's location as shown on the diagram to the right.  On the other side of the center of flotation (CF), measure the stabilizing force of the keel or movable ballast, i.e., water ballast, crew, etc..  Removing 200 lbs. from the rig with the boat heeling 15 degrees would have the similar effect of adding 200 lbs. to the keel, or only 100 lbs. on the beam rail.  Adding water ballast or crew on the boat's rail is the least expensive and most dramatic stabilizing force, especially within the optimal heeling/performance range for the modern sailboat.

   © 2013  Maxi Marine, All Rights Reserved.   home

How Does Sailing Ballast Work and Why Do Boats Need It?

What is a sailboat ballast.

Sailboat ballast is a weight carried either in the sailboat keel or hull, typically made of lead, iron, or cement, which acts as a counterweight to the wind's force on the sails' force, providing righting moment by lowering the center of gravity.

Where is the ballast in a sailboat?

Ballast can be carried either in the sailboat keel (keel ballast) or hull (internal ballast). Generally, the majority of the ballast will be located in the keel, since the lower the ballast, the more righting moment it provides.

Where do you put ballast on a boat?

You want to put your ballast in the lowest point of the boat. Typically, ballast is stored in the bilge, where it will have the most effect.

Why do boats need ballast?

Boats use ballast to offset their hull's inherent buoyancy, which creates a tendency to roll. Ballast increases the displacement by lowering the center of gravity, increasing the amount of wetted surface. This improves stability and reduces roll or heel.

How does a boat ballast work?

Boat ballast is a weight that is typically added to the bilge or the keel of a ship in order to increase the weight while simultaneously lowering the center of gravity of the boat. This increases the displacement and the wetted surface, which in turn increases stability and reduces roll.

Sailboat ballast material

Sailboat ballast is usually made from lead or iron , but sometimes cement or water is used as well. Lead is the most expensive ballast material but also has the highest specific weight, reducing the volume.

How much ballast does a boat need?

The amount of ballast needed for a boat depends on several factors, such as displacement, hull design, and boat type. The desired amount is generally expressed as a percentage, also called the ballast displacement ratio . In sailboats, the average ballast ratio is 35-40%, with weights ranging anywhere from 200 to 12,000 pounds .

What did sailing ships use for ballast?

Wooden ships typically used ballast stones, but sometimes extra anchors and cannons were used. Depending on the weight of the cargo weight and crew, ballast stones were added or removed to change the ship's weight accordingly. Ballast was kept in the bilge to lower the center of gravity.

Does sailboat displacement include ballast?

Displacement is always measured including ballast, since adding ballast increases the total displacement.

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You may also like, sailboat keel types: illustrated guide (bilge, fin, full).

The keel type is one of the most important features of your boat. But the different designs can be confusing, so I've set out to create a very clear guide that will …

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Water Ballast Boats ?

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Hello All; Are there some readers who have experience with Water Ballast boats? If so, what kind of boat(s)? Please tell us about it - pros and cons. The MacGregor 26 is the only one that I know of. I have heard that it is not a great sailboat. It is, perhaps, a better power boat. What other boats in the 20' - 30' range use Water Ballast? How well do they sail? Thanks, Richard  

I learned to sail on a Hunter 240. Nice trailer sailor with decent room down below for a boat that size. Nice to sail on a nice day. Not something I would want to be out on if, as it does in New England, conditions changed quickly. Nor is it something I would want to use for coastal cruising. Water ballast is a trade off I'm not willing to make. However, IF I had to start towing a sailboat on a trailer I might have to rethink my options. At this point I do have options, I could trailer, use a slip, dry store or stay on a mooring. A keel boat on a mooring, for me, is by far the best option. (One thing you don't mention is why you are interested in water ballast) JMHO YMMV  

RobGallagher said: . . . . A keel boat on a mooring, for me, is by far the best option. (One thing you don't mention is why you are interested in water ballast) JMHO YMMV Click to expand...

If you you're not planing on take your bot out of the water after each sail, or if you won't be trailering the boat much, I wouldn't choose a water ballast sailboat. But to answer your question: MacGregor 26 Hunter 240 Hunter 260 Catalina 250 mkll I have only sailed on the MacGregor 26 and didn't really enjoy it, I can't say anything about the other sailboats listed above but I am thinking that they are probably better boats then the MacGregor. Pros: -If bad weather is on the way your can lower your sails, dump the ballast and plan back to your marina/mooring -easy to transport -If you manage to poke a hole ( in the water ballast tank) through the hull it shouldn't sink Cons -Ballast isn't down low where it should be -Water density 62lbs per cubic foot, lead density 709 lbs per cubic foot= tender sailboat -less head room -Hard to access and inspect the ballast tank (I don't recall seing a inspection port in the MacGregor but I could be wrong please correct me if I am. I don't know about the other boat listed above) And this is probably just me but I'm always scared to loose all my ballast while I'm sailing on one of these boats =D Cheers Pierre  

And this is probably just me but I'm always scared to loose all my ballast while I'm sailing on one of these boats =D Click to expand...

In looking through the archives, I found several threads from years ago. One problem I had not thought of is Marine Growth in the water ballast tanks - when the boat is sailed in salt water. Can anyone comment on that? As for stability and sailing performance, the old posts tended to recommend weighted lifting or swing keels rather than water ballast. What do you think? Richard  

rlltrash said: In looking through the archives, I found several threads from years ago. One problem I had not thought of is Marine Growth in the water ballast tanks - when the boat is sailed in salt water. Can anyone comment on that? Click to expand...

rlltrash said: ...As for stability and sailing performance, the old posts tended to recommend weighted lifting or swing keels rather than water ballast. What do you think? Click to expand...

In looking through the archives, I found several threads from years ago. One problem I had not thought of is Marine Growth in the water ballast tanks - when the boat is sailed in salt water. Can anyone comment on that? Click to expand...

As for stability and sailing performance, the old posts tended to recommend weighted lifting or swing keels rather than water ballast. What do you think? Click to expand...

With the high coamings even if the boat is knocked down for a second no water enters the cockpit. Click to expand...

In addition to the valid points made above, two items occur to me about water ballast: 1) To have anyting near enough righting moment with water ballast being carried so near the surface of the water, MUCH more weight has to be pumped inside the hull. At best, your sails create just a few horsepower to propell your boat. Remember that you have to accellerate the total mass of your boat (including water used for ballast) with that limited power every time you tack. 2) Being able to tow a water ballasted boat with a smaller vechicle dosen't seem valid. Unless there is a pump to evacuate the water used for ballast while the boat is still in the water, the weight must be pulled up the ramp to drain by gravity. While you might not need a Power Wagon to tow down the road, you will need it for that first few feet up the ramp. A smaller, more economical tow just isn't likely to do it. The main advantage of water ballasted boats has always looked to me like it is mainly for the builder. They are selling you empty space inside the hull and a couple of valves instead of lead. Are these boats any less expensive?  

Richard, The water ballast on the M26 S is accessed just underneath the companionway steps. The single ballast tank has a removable plug in the cabin that would allow you to put some bleach in there if you felt it necessary. There is a long bolt that you loosen to let water into the ballast tank once you launch and tighten once full. Loosen the same bolt once the boat is back on the trailer and all the ballast water drains out, eventually. I've sailed a M26 S for about 50 miles on the Atlantic from Fire Island Inlet to NYC. It was a very benign day for the most part. Because of the relatively light weight of the boat (~3000#'s with ballast full) it tends to ride over the waves rather then through them as a heavier boat might. On a choppy day this tendency might make the boats motion a bit uncomfortable but if the waves are far apart it should not be a problem. We had lazy 3' swells that the M26 S seemed not to notice. On this trip we did get some wind as we neared NYC and my GPS indicated a ground speed of around 6.5 knots, if I recall correctly. 6.5 knots is faster then my heavy Tartan 27' can do on a good day. The same could be said for most 27' keel sailboats made by Catalina, Hunter, O'Day or whomever. There is a trailer sailor forum as well as MacGregor owner forum at SailboatOwners.com - Latest forum activity if you want to trade notes with other Mac owners. Most people who have never sailed a Mac 26 S or D tend to lump all the models together and deride them for no good reason. They are not overbuilt like my 1967 Tartan 27' but they are good at what they do. The cabin interior of the M 26 S is bigger then my T27 if you don't mind not being able to stand up. All boats are compromises and the M 26 S design did not sacrifice much in the way of sailing ability.  

Thank you all very much. Are there any more Hunter or Catalina sailors who can comment on their boats? Also, unless it is noted above and I missed it, how many gallons of water do these water ballast boats carry as ballast? Are they all about the same, or do some carry significantly more water ballast than others? Thanks, Richard  

rlltrash said: ...Also, unless it is noted above and I missed it, how many gallons of water do these water ballast boats carry as ballast? . Click to expand...

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What Is a Ballast on a Boat? (For Stable Floatation & Easy Boating)

Written by J. Harvey / Fact checked by S. Numbers

You may wonder “what is a ballast on a boat” and how does it work for easy and safe boating? Boarding a stable vessel that strides over tides without the risk of capsizing is possible because of a boat’s ballast.

The “ballast” of a boat provides stability while lowering gravitational balance and reducing the roll. This can be a “ballast tank or bag” containing water or other counterweights to increase boat displacement.

Read on to learn more about various effective marine ballasts and how seasoned boating experts enjoy using them.

Table of Contents

1. Simple Description Of An Effective Boat Ballast

2. the basics of adding a boat ballast, 3. marine ballast variants, 4. the power of boat ballasts, 5. water ballast technology systems, 1. what are ballasting and deballasting, 2. how does a ballast system work on a boat, basic guide about a boat ballast and how it works.

The boat ballast meaning varies based on where it is used: a sailboat, angler, airboat, or air balloon. Usually, a ballast comprises water but also uses other counterweight methods for a specific boat or boating need.

Like a small boat ballast, it needs the traditional use of ballast stone, water, lead, steel, cement, or sand materials. The water ballast sailboat effectively increases displacement against strong water or wind pressures by having a ballast keel.

The concept of older boat ballasts like the year 1700 ship ballast types and those in sailboats are still relevant today. Before, larger boats even used stones or sand as a ballast keel for floatation stability.

Years passed and ballasts evolved into advanced marine counterweights to pull dive deeper into the water, and thus, lower the center of gravity and displace water to improve floatation.

This means that the more weight your ballast can provide, the better the boat can settle in the water. It keeps hulls covered well in water for more boat balance, a dry deck, and better water wake.

Explore the basic tips for adding ballasts for a safe and well-balanced sailboat, yacht, fishing, wakeboard, and other vessel types here.

• Read about the best practices and secure the right boat ballast installation diagram to customize it.
• Know the space requirements for the ballast and the ballast size you want to use for your intended purpose.
• Check that your ballast features meet your expectations for big species fishing, recreational purposes like wakeboarding, etc.
• Consider the carriage capacity of the boat to select a boat ballast that serves as an effective counterweight.
• Compute for the freeboard, water displaced, or deadweight tonnage and draft calculations to know the effect of adding your ballast.
• Add sufficient counterweight to prevent the boat from tipping or heeling when exposed to excessively high waves and winds.
• Know whether a fixed, portable, or manual ballast system works for your boat by using a boat ballast calculator. Adding the appropriate type of ballast to your boat should be within the boat weight and buoyancy or floatation ability.

Aside from a water ballast and the materials mentioned above, there are other variants to consider for your vessel. Adding the right ballast type is vital, especially for ocean goers, like open-sea fishing, tanker, or barge and cruise ship.

Though they differ in names, they are basically classified as a clean ballast (CBT), and segregated ballast type (SBT). Each ballast needs to be shaped and secured firmly so it will not upset the ship’s balance or damage it.

Also, larger boats like yachts use water or lead ballasts in their keel or lower hulls with pipes and pumps. This additional weight helps keep yacht cruisers and barges floating upright for long stationary hours in the water.

Marine ballasts differ from simple to advanced materials and construction but all need safe handling, precision fitting, and sediment flowability. Essentially, heavier ballasts can lower boats in the water for maximum stability and create a better wake.

People tend to believe that each boat’s ballast type is much greater than the other, like using a water ballast . But the truth is, all of them are powerful counterweight measures when they are used accordingly.

• The boat ballast weight or additional mass needed depends on the boat’s displacement need, weight, and buoyancy.
• Check your desired ballast weight with the boat’s weight based on boat displacement or the weight of the water it displaces.
• Consider using stone, lead, iron, or cement to make a powerful sailboat ballast. Ensure the ballast is movable or designed to prevent further modifications to the layout of any boat.
• Add or reduce by one inch the weight of your boat in the water to see the difference when it’s floating. You can check different weight charts that apply even for small cruisers, yachts, or dinghies and tenders.

Today, boats use water ballasting or deballasting systems, which are handier and safer. This liquid boat ballast system consumes less time and maximizes the already available seawater whenever needed in huge amounts.

In the old days and in some boating environments these days, solid ballasts are used for boat stability. This applies for sailboats to ease out movements, and cargo loading and discharging where the portage is minimal.

The good thing about a water ballast system is it can become lightweight when there is cargo on the ship. The ship’s cargo maintains the stability itself requiring little to no ballast water and can quickly flow when needed.

Ensure to adhere to port authority requirements wherever you need to drain sediments or take water to the ballast tank. You need to have a water management plan when your ship navigates in foreign or a state’s terrestrial waters.

Learn more from this YouTube Video from Bar Crusher Boats on how a water ballast “Quickflow system” works.

Frequently Asked Questions About a Dinghy or Tender Boat

It’s the process of taking in and draining out seawater from the boat ballast tank for proper weight balance. The ballasting and deballasting process ensure structural integrity and stability of the ballast tank while at port or at sea.

Most ships with water ballast systems have piping and high-capacity pumps to ease the ballasting and deballasting process.

Installing a ballast system on a boat helps you keep stable access while navigating without the fear of tipping over. It also provides better storage for long periods or winterization purposes while preventing any damage.

Providing stability to your boat needs an additional solid, metal or water weight on the ballast tank or compartment. In addition, it is necessary to ease out the gravitational pull by displacing the weight down and putting dense water out for a better wake.

I’m certain you now know “What is a ballast on a boat and how does it work?” It’s your life-saving option to stride over strong tides without worries of capsizing.

Use these recommendations from experienced boaters to guide you in using your boat ballast tank. Operate your boat and enjoy proper displacement control of your ship to navigate smoothly and handle opposing buoyancy.

Continue learning these boating expert insights to ensure a safe and convenient boating experience. We hope you’ll share this review and feel free to share your thoughts about it with us.

“My intention from the first day establishing Boating Basics Online is to provide as much help as possible for boaters who want to experience a first safe and convenient trip. So feel free to join us and share your beautiful journeys to the sea!”

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• Sailboat Reviews

Hunter 23.5

This family cruiser is innovative and has lots of room. in gusty winds, however, it is quick to stall..

Hunter Marine Corp. is noted for its slick, innovative and low-cost mass production sailers. The Hunter 23.5, new in 1992, fits the bill in all respects.

The 23.5 was designed as a trailerable family cruiser for entry-level sailors. Like most Hunters, the boat offers lots of space in the cockpit and down below, and comes with the famous Cruise Pac, which provides just about anything a customer needs, including sails, motor, trailer, lifelines, anchor, life jackets, flares and a copy of Chapman’s Piloting, Seamanship and Small Boat Handling . It’s this type of marketing (plus price: the 1992 price was $13,500) that has helped make Hunter one of the most successful sailboat producers in the U.S.

No one has ever faulted the Alachua, Florida, builder for offering anything but fresh, well-thought out designs. The most striking feature of the 23.5 is its water ballast system, new to Hunter. The system permits an operator to remove 1,000 pounds of ballast from the trailering weight. A retractable centerboard, kick-up rudder and mast that’s fairly easy to step and unstep further enhances trailerability. All told, boat, motor and trailer weigh a combined 2,450 pounds. This model also contains enough foam to provide positive flotation.

While Hunter has enjoyed considerable success with the buying public, it has also suffered from a negative image problem. Earlier PS reviews have criticized Hunter products for a lack of quality control-various systems kinks, lightweight hulls, poor finish work and general absence of blue-water seaworthiness. On the other hand, Hunter owners, while acknowledging a prevailing lack of respect, frequently defend their choice. In the realm of objective data, Coast Guard complaint and recall statistics reveal that Hunter has a better than average record when it comes to hull blistering. (Hunter offers five-year bottom blister warranty protection for the 23.5.) Clearly, the company is doing something right. The model we inspected (hull #8) showed, with very few exceptions, careful attention to detail and finish work in even the least accessible places-more than youd expect on a $13,500 boat. But it is also a boat with some inherent contradictions, in our opinion.

The 23.5 is a highly engineered product with lots of thoughtful features. Hunter, unlike some builders, constructs a mock-up, followed by a prototype that is extensively tested before final design decisions are made. The hull form is modern looking, almost powerboaty in appearance from some angles. Continuing a tendency evident in recent Hunters, the design team has given the 23.5 a relatively full hull, and raised the freeboard to reduce the cabin height, as well as add room below and keep those up top dry in a chop. Because the cabin extends to the rail (no side decks), you must climb over the cabin top to get to the foredeck.

The rig (a B&R design) consists of a 28-foot Z. Spar mast, fractionally rigged with swept-back spreaders that eliminate the need for a backstay (and make un-stepping/stepping, hence trailering, simpler); for the most part, the uppers are aft of the “after” lowers-until deck level-creating a triangular support system. Main and jib halyards are internal and led back to the cockpit. Power comes from a fully battenedmainsail and 110-percent jib (UK Sailmakers-Hong Kong) with a total of 236 square feet. For steering, the traditional wooden tiller has been replaced with a brushed aluminum tube that arches over the walk-through transom (swim ladder comes standard). The aluminum, said chief designer Rob Mazza, weathers better and is easier to arch in order to keep the rudder low and the tiller sufficiently high. Many helmsmen will use the standard Ronstan X-10 tiller extension.

The water ballast/keel system constitutes the key feature of the 23.5. The water ballast-125 gallons, or 1,000 pounds-takes about two minutes to bring on board. The system is activated by flipping up a lid at the base of the companionway, opening a vent and turning a T-valve; the valve in turn drops a circular stainless steel plate aft of the keel, exposing four holes in the hull. (The plate can then be closed flush.) And while you can’t jettison the water downwind, you can swing up the centerboard to reduce draft to 18 inches. The 4-foot centerboard, controlled by the outboard line to the cockpit, moves easily up and down via a cascade block and tackle arrangement.

The apparent thinking of Hunter engineers was to provide a simple, one-step water ballast system that keeps draft shallow while lowering the center of gravity for added stability and righting moment. The ballast-about 16 cubic feet in volume-lies immediately below the waterline. When the water is added, the boat sinks several inches. Nevertheless, while the water adds 1,000 pounds to the overall displacement, its location does not seem to provide sufficient righting moment for windward work in gusty conditions. On racing boats, water ballast is carried above the waterline and outboard under the settees, which of course provides more righting moment. But this water must be pumped into the chambers and drained before tacking-too complicated for Hunter’s purposes.

Construction of the boat is fairly straightforward, with balsa in the hull and plywood in the deck. The plywood core has the potential to encourage water migration should a deck leak occur at some point. The deck/hull joint, with a roll similar to a Hobie 18-a “modified shoebox,” one Hunter engineer described it-is bonded with glass and further fastened by flathead screws through the rubrail. Stanchions, fastened to aluminum backing plates that are glassed in, are sturdy. Though not a heavily-built boat, the 23 looks solid enough; in the absence of a graceful hull form-no sheer here-Hunter provides some added dash with a smoked forward-facing window and a green and purple hull swoosh graphic, which apparently has drawn strong reaction, pro and con (We liked it). Oddly, there is no waterline or boot scribed in the hull. Perhaps Hunter anticipates owners dry-sailing the 23.5, but the absence of a waterline mark will make bottom painting a difficult chore the first time.

Performance

We test sailed the 23.5 off Newport, Rhode Island. In light-air conditions, the shallow-body, lightweight boat (displacement 3,000 pounds with the water ballast) moved up to speed quickly. The boat pointed high and the few light puffs we experienced produced no noticeable helm. We did have some problem finding a definitive groove, especially after tacking. The boat glided through the water easily on a reach and downwind, with the board up, sped along as much as a 23-footer can (Mazza said it will surf under the right conditions). We moved relatively faster, in fact, than a Nonsuch 27 on the same tack.

In stronger 15-20 knot winds, it is a whole different experience. With a single reef in the mainsail, the boat consistently rounds up and stalls. In addition to the boat’s higher vertical center of gravity, this tendency may also be due to the very high-aspect ratio centerboard, which is generally associated with quick stall characteristics.

Complicating matters is the way the rig and sheeting are set up. With no backstay (or topping lift) and no traveler, and with the main sheeted down and far forward near the companionway, the main and sheet are highly stressed. And because the cam cleat for the mainsheet is down near the cockpit sole, it’s difficult to reach-especially in heavy air on a beat, when the helmsman and everyone else is out on the rail. The rounding up and stalling require constant spilling of the main. This may be okay (if tiring) for the experienced sailor, but a bit strenuous and nerve-wracking for the beginner at whom this boat is marketed.

Instead of a single reef, one solution might be to take a second reef in the main in anything approaching 15 knots, but that’s not much of a solution. With 236 square feet of sail-128 in the main, 108 in the foretriangle-for a sail area-displacement ratio of 18.9, the boat should not be overpowered. (The O’Day 23, of about the same displacement, but with 200 more pounds of ballast, carries 246 square feet)

Another solution, although it breaks up the cockpit, might be a barney post where there’s already a slot for the cockpit table, a system that worked well enough in the Alerion-Express. A traveler would be even better, though obviously Hunter wanted to keep the cockpit clear of obstructions as well as avoid the added cost.

Accommodations

You get a lot for your money with this Hunter model. One thing you get a lot of is interior space or, as company literature describes it, “a 25-foot boat in a 23.5 hull.” The main cabin is sizable and has more headroom than we’ve seen on a 23-footer. A pop-top hatch allows those down below to stand up in the center of the cabin. An optional canvas camper top ($300) provides protection from the elements. Poptops are notoriously leaky, and we can’t vouch for this one’s water tightness; however, Hunter has provided drains all around.

The smoked pop-top, plus three ports per side in the main cabin (two small circles, one longer swoosh-style forward) and the forward-facing window provide plenty of light. Hunter has made no attempt to yacht-up the interior: What you get is a basic cream-colored liner, offset on a portion of the topsides by a close-weave grayish fabric someone called “monkey fur.” Despite the plainness, we liked the clean look of the interior.

Aft to port in the main cabin you get a galley station with a one-burner alcohol stove, sink, and fold-out table with storage below. You won’t be whipping up any Cruising World -style feasts in this galley, but it’s nice to be able to heat up some coffee or a cup of soup. Forward of the galley is a small settee/berth, sized right for a child, with storage beneath and a cutout for a portable ice chest. Opposite is a somewhat longer settee/berth of less than six feet, with more storage and a battery compartment below. On the centerline is a slot for a small table that also can be set up in the cockpit.

There are a number of helpful additions: an automatic bilge pump, access plates underneath the cockpit winches. The portable toilet is located to starboard behind a half-bulkhead and privacy curtain, and under the V-berth. Aside from the standard V-berth in the bow, which seems a bit cramped, there’s a double berth (plus stowage) aft of the main cabin, under the cockpit and seats (not for the claustrophobic). It was back here in the bowels of the boat that we spotted the only untrimmed fiberglass.

On deck, there’s an equally roomy cockpit-7′ 9″ long and 6′ 2″ from coaming to coaming. The relatively wide beam makes the addition of a ridge along the centerline for use as a footrest a welcome touch. Foam padding on the seatbacks is another. A lazaret on either side provides on-deck stowage. There’s a #8 Barient winch on either side of the cabin top, each with an attendant cleat. Lines are meant to be kept in the no-name stoppers to starboard. Because of the profusion of lines led back on the starboard side, we’d prefer an extra cleat and winch.

Nonskid is molded in. The foredeck holds an anchor locker, which also contains a padeye for the stepping/unstepping operation. Skipping the details of this procedure-which involves use of a gin pole, the main and jib halyards and a bridle that controls lateral movement-we’d say that Hunter has devised as easy a way to drop a mast as is possible. Once down, the forward end rests in a U-shaped bend in the bow pulpit, the aft end on a roller-topped pole fitted at the transom.

Conclusions

In its attempt to create a simply operated, easily trailered, entry-level boat at a good price, Hunter has come up with some clever compromises. But they are compromises just the same. The 23.5 sails well on all points in light air; it does well off the wind in heavier air. Windward work over 15 knots in this boat is poor in our estimation. We’d strongly recommend that potential customers thoroughly test sail the boat in a variety of wind conditions, experimenting with one or two reefs, to be certain it’s something they’re able-and willing-to handle.

The Hunter 23.5 is clearly striking a chord with some buyers, and assuming many are entry-level sailors, we think it’s great that this boat is attracting newcomers to the sport. The design represents a clever way of managing the trailering problem (i.e., weight and draft). At the same time, we can’t help but wonder if its behavior in gusty winds is worth the convenience of dumping ballast on the launch ramp.

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excellent article.

Darrell – excellent review. Thanks.

Thanks for the review, I just saw one for sale online.

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A Waterspout Was Seen When a Luxury Yacht Sank. What Is It?

Witnesses reported seeing the tornado-like phenomenon hit the Bayesian, a sailing yacht that sank off the coast of Sicily on Monday.

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By Eve Sampson

What caused the sinking on Monday of a sailing yacht carrying the British billionaire Mike Lynch and 21 other people off the coast of Sicily is still unknown. But some attention has focused on observations by witnesses, who described seeing a small tornado-like column known as a waterspout forming over the water during an abrupt and violent storm as the vessel sank.

Fifteen passengers on the 180-foot yacht, the Bayesian, escaped on a raft before being rescued by a neighboring cruise ship. The body of the ship’s cook was recovered on Monday and six people remain unaccounted for , including Mr. Lynch and his daughter Hannah, according to officials with Sicily’s civil protection agency.

Prosecutors in the nearby city of Termini Imerese have opened an inquiry into the cause of the sinking.

Here is what to know about waterspouts, a surprisingly common weather phenomenon that may have helped sink the luxury yacht.

What are waterspouts?

Waterspouts are columns of spinning air and moisture — similar to tornadoes over water, according to the National Weather Service .

While some form in fair weather, and are aptly called fair weather waterspouts, another more dangerous variety called tornadic waterspouts develops downward from a thunderstorm. These tornadic waterspouts can either form as regular tornadoes over land and move out to sea, or form in a storm already over a large body of water, according to the National Oceanic and Atmospheric Association .

Fair weather waterspouts are weak, often dissipate quickly and do not cause major damage, according to the agencies, but tornadic waterspouts are more often associated with high winds, dangerous and frequent lightning, and hail. The Italian authorities recorded strong winds and intense lightning activity at the time the yacht went down.

How common are waterspouts?

Experts say waterspouts may be more common than tornadoes, but because oceans are so vast, they are more difficult to track — and as difficult to predict.

“The Mediterranean is possibly one of the places where waterspouts are most likely around the world due to the warm ocean surface and a climate that is very susceptible to thunderstorms throughout the summer and autumn,” according to a statement by Peter Inness, a meteorologist at the University of Reading in the United Kingdom.

Mr. Inness pointed to a 2022 study by scientists from University of Barcelona , which found that waterspouts occurred more frequently over warmer sea surfaces. The North Atlantic ocean has been unusually hot for over a year, repeatedly reaching record highs for the time of year , according to data from the oceanic association.

The International Centre for Waterspout Research on Monday said on X , the platform formerly known as Twitter, that it had confirmed 18 waterspouts near Italy in recent days, and several fishermen in the area of the accident told Italian media that they had witnessed a waterspout near the yacht.

What may have happened?

Karsten Börner, the captain of the nearby boat that rescued the 15 passengers, said in an interview that he saw the Bayesian about 490 feet away before the wind and lightning picked up.

While it was difficult to see what happened amid the storm, “my theory was that she was capsized first and then went down over the stern,” he said.

Towering over 237 feet tall, the Bayesian mast was one of the tallest aluminum masts in the world and it also had a special keel that could be raised or lowered, according to its manufacturer, Perini Navi. A keel is the downward-extending centerline underneath a boat that can help stabilize the vessel.

“In this case, having a tall aluminum mast would not make it the safest port to be in case of a storm,” said Andrea Ratti, associate professor of nautical design and architecture technology the Politecnico di Milano.

He added that “a lot of questions will remain until we have other elements at our disposal.”

Elisabetta Povoledo contributed reporting.

Eve Sampson is a reporter covering international news and a member of the 2024-25 Times Fellowship class, a program for journalists early in their careers. More about Eve Sampson

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Hunter water ballast operation

• Thread starter Chris Akeley
• Start date Jun 16, 2005
• Hunter Owner Forums
• Ask A Hunter Owner

Chris Akeley

Hello! I'm about to take delivery on a Hunter 23.5 and the broker could not explain to me how the water ballast system works. (He was very helpful otherwise..) Can anybody offer insight as to operation, care, and feeding of the water ballast system?I imagine this is common to all Hunter water ballast boats in the 23 foot size range.  

Water Ballast Congratulations on your new boat, Chris!The water ballast system is simple but must be managed properly. Here are the steps I recommend you follow. I have a Hunter 260. I don't know where the valve is on a 23.5 or how it works so I'll be general about that part and let someone who knows give you the details of where the valve is and how to operate it.1) Close the valve before launching so water doesn't rush in before you get the boat off the trailer.2) Once away from the trailer and safely tied to the dock or floating free away from other boats, open the valve to allow the water to flood the ballast tank.3) There should be a 1" hole with a drain plug fitted that you will use to determine when the tank is full. When you can put your finger in water by sticking it in the hole, it's full.4) Close the valve securely so when you're heeling it won't run out.5) When coming back to load the boat on the trailer, remove the plug and open the valve. Then pull the trailer up the ramp slowly to let water drain. Remember it's hundreds of pounds heavier now, so instruct the driver to be smooth and slow about taking the boat and trailer up the ramp and parking it for de-rigging.Email me directly if you have other questions since I don't check this board every day.[email protected]Best wishes and great sailing to you, Chris.  

Rick Macdonald

Some more... The valve is under the bottom wooden step going down into the cabin. The ballast weighs 1000 pounds, so unless there are people on the ramp yelling at you, you might want to pull it up just a few feet and stop for a few minutes while the water runs out.6) The manual suggests leaving the ballast tank valve open during winter storage if you live in a freezing climate.7) Some sailors say they put a cup of bleach in the tank to help control odor. I assume this is only in salt water, and only if they have a slip or mooring and leave the boat in the water for months at a time? Or maybe they do it even for weekend launches? Maybe in fresh water too? Sorry, I'm not sure. I sail on fresh water that is relatively cool and it doesn't smell after 4 months.Enjoy the boat!...RickM...  

Bleach I sail and moor my 23.5 in a fresh water lake, and have for 10 years. At first launch each Spring, after flooding the ballast tank and closing the valve, I add a full gallon of household bleach to the tank, using a funnel to pour through the air-escape hole. I have never had a problem with odors, or with any ill effects from the bleach. A gallon of bleach in a couple hundred gallons of water is minimal.  

1/2 liter of bleach I keep my 240 on a mooring in salt water. I put a half liter (a water bottle full) of bleach down the vent hole on the ballast tank once it's in the water, and I've never had any detectable odors, with the boat in the water for up to eight months.  

Paul J. Rusyniak

Chris If you’ve launched in an area with murky water and you’re going to motor out into an area with cleaner water, I suggest you hold off filling the ballast until you’ve reached that cleaner water.Maybe I’m just anal, but I see no reason to get silt or other debris in the ballast tank.Enjoy your new boat!!!Pauls/v The Lord Nelsonh260  

ray espinosa

water ballast I sail a 1993 Hunter 23.5. I keep the boat on a trailer in the Marina and fiil the tank at eachlaunching. My valve closes before the tank fillscompletly unless I hold the valve down with my hand. Be sure the tank is completly filled.When I first bought the boat I went out a few times with the tank only 2/3 to3/4 full.with apartial tank it heals 25 to 30 degrees in 5-10knot winds and rounds up in gusts of 15+.  

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