I keep hearing about davits on catamarans and after seeing a boat that was for sale with a broken davit (and missing its dinghy) I wanted to know more about them, so I did some research and learned a lot.
What are Catamaran Dinghy Davits and Why Do You Need Them? Catamaran davits are a set of crane like arms, typically fabricated out of stainless steel, mounted to the back of the sailboat between the transom steps, with the purpose to lift the dinghy with outboard up out of the water to secure it for sailing and also for security while at anchor. There are many different sizes, shapes and kinds of davits for catamarans.
Dinghy Davits on Catamarans (why you need them)
You don’t actually need dinghy davits but having properly engineered davits on your catamaran can make your life much more convenient and save you lots of headaches and money. You don’t absolutely need dinghy davits on a catamaran or sailboat. As I will explain later in this post, there are other, less convenience ways to lift your dinghy onboard. Other methods may also increase your personal risk of injury as moving around a dinghy and motor weighing several hundred pounds can be hard on your body and deck (and its just a lot of work).
Dinghy Theft Prevention
Dinghy theft is on the rise in many popular boating locations throughout the world. Keeping the dinghy in the water at night while you are sleeping and even during the day when you are not on the boat greatly increases your risk of having the dinghy or outboard motor stolen. For more about boating theft, noonsite.com provides an excellent free service of posting boating incidents throughout the world.
Why is a Good Dinghy Important?
The dinghy is like the family car for catamaran (and many other sailboat) owners. Unless you are spending all your time in a marina tied to a dock (and even sometimes when you are at a marina), you will need a way to get around. The dinghy allows you to drop the hook (anchor) and get to shore without having to swim. It is how cruisers go to the grocery store, explore islands, visit other boats, get to dive and snorkel locations, explore, walk the dog and get around without moving the entire boat off the mooring or anchorage. The more time you spend on your sailboat, the more important the size of the dinghy and the size of the outboard engine on the dinghy. The larger the dinghy, the more effort it takes to lift the dinghy in and out of the water. That’s where the davits come in.
Choosing the Right Size Dinghy
Choosing the best dinghy for your needs, boat and davit system is an important consideration. You want a dinghy that is large enough to fit your family and/or crew, carry your groceries, and family pet. You also want a motor that will allow you to get up on a plane when carrying the family and/or crew, groceries and pet. But (yes there is always a but), you don’t want to go too large that you outweigh your davit system.
Broken Davits Equal Lost Dinghys
I recently looked at a Lagoon Catamaran that was for sale. It had recently finished an Atlantic Ocean crossing. Not only was it missing one of its davits, but it was also missing its dinghy. I didn’t get all the details, but I can make an educated guess that either the dinghy was too large for the davit system or it wasn’t secured properly. I can also assume that the missing davit was the one on the outboard engine side of the dinghy (which holds most of the weight).
Which is First, Chicken (Davit) or Egg (Dinghy)?
If you are buying a used catamaran, then this decision may already be made for you, but if you need to purchase a new dinghy or both dinghy and davit system, then you need to think about engineering your davit prior to buying the dinghy. At least have an understanding of the limitations of each type of davit system and what it can hold. Buying too large of a dinghy or having undersized davits can be more than an inconvenience.
Important When Buying a Used Catamaran
Make sure your surveyor checks the davit system and provides information about the limitations of it. Many used catamarans have replaced a good dinghy with a smaller, cheap one. Don’t just think you can upgrade the dinghy without considering the davits. If you need to change both dinghy and davits it can set you back (cost you) tens of thousands of dollars, something you will want to upfront before purchasing.
Don’t Assume the Last Owner Did it Right!
When buying a used catamaran that has the perfect dinghy, don’t assume the last owner sized the davits correctly. Many used boats come out of charter and don’t experience rough seas from crossings or challenging passages. The charter companies restrict where they can sail to mostly calm seas. Once again, make your davit system is inspected by your surveyor for proper sizing, installation and any signs of stress.
Engineering the Davit System for the Dinghy
It is important to size the davits for the dinghy that it will be carrying. One common mistake is to take the overall weight of the dinghy and divide by the number of davits (two). So, if the overall weight of the dinghy is 400 pounds, the wrong way to size the davits is to carry 200 pounds each. Keep in mind that the outboard engine most likely will account for up to eighty percent of the weight of the dinghy so the davit carrying the engine side needs to be sized accordingly. Better yet, oversize both davits so that if the dinghy ever gets loaded in reverse or fills with water, it doesn’t get lost.
Properly Securing the Dinghy
Securing the dinghy to the davits is a critical step in maintaining the integrity of the davits. Going back to the example of the 400-pound overall dinghy weight, we can demonstrate how an unsecured dinghy can add a lot of stress to the davits. When the dinghy is secure it doesn’t move and generally, speaking the actual weight of the dinghy is what is transferred to the davits.
What Happens when it’s Not Secure (Fail)
When the dinghy isn’t secured properly and allowed to move around, additional weight and stress is transferred to the davits. Now imagine what happens to the dinghy when you are out at sea. Even in moderate seas, the dinghy is bouncing around and swaying back and forth adding not only downward pressure, but also side to side pressure to the davits. Over time (or the first time), this stress can cause a failure – a very expensive and potentially dangerous failure.
Boats Without Davits (Lifting the Dinghy)
So how do you lift the dinghy when there are no davits? There are a few ways to do it. Any sailboat with a boom can use it like a crane to lift the dinghy. Lift the outboard motor first, then the dinghy. This works great and is the way many smaller monohulls do it, though it does take a fair amount of effort. Of course, you can also lift it by hand, but you need strong crew in order to lift it this way and the chance of dropping it is increase. Some large catamarans have a dinghy garage and don’t need davits. Others have a large swim platform that raises and lowers to store the dinghy. If you are an experienced sailor and have seen or used another method, please share it in the comment section below (we would love to hear about it).
Towing Your Dinghy Behind Your Boat
You can tow your dinghy behind your catamaran. This isn’t recommended for long crossings or if you are expecting heavy seas and it may slow you down, but it is another way to move your dinghy. Of course, towing your dinghy doesn’t help with security while at anchor. You’ll have to think of another way to secure your dinghy and outboard when you are not using it.
How to Get the Dinghy in and Out of the Boat (With Davits)
Dinghy davits are one of the easiest and most convenient way for catamaran owners to raise and lower the dinghy in and out of the water. Rigged with pulleys and a winch, it is much easier than doing it by hand. There are many different davit systems, but generally this is how it works.
First, you connect the lines from the front davit to the front of the dinghy. Then you connect the lines from the rear davit to the dinghy. You can pull the lines manually or if equipped with a winch nearby, wrap around a winch and use it. The winch can be a hand crank or powered. Some systems are set up to lift the front and back of the dinghy at the same time with one line to the winch. For other systems, you may pull the front part way, then the back and back to the front, etc.
How to Drain Your Dinghy
Before pulling the dinghy all the way up, raise the front up higher than the rear. This allows you to drain any water (extra weight) that may be in the dinghy before securing. When all the water is out you may want to replace the plug in the dinghy (so you don’t forget before using) and finish raising both the front and the rear to their maximum positions. If it is raining or you are not going to be using the dinghy for a while, you may consider keeping the plug out so that the dinghy doesn’t fill up with water, which can add significant weight to the dinghy and stress on the davits.
Water Weight Can Add Significant Stress to the Davit System
Water weighs 8.33 pounds per gallon. Think about how much water your dinghy can hold, then do the math (Length of interior space X Width of interior space x 7.5 x 8.33 will get you close to the weight in pounds). Of course, if you need to collect water, keeping the plug in allows the dinghy to double as a water collection device. Just make sure that your davits are designed to hold the additional weight.
A Swinging Dinghy (My Favorite Band)
Yes, that title made me chuckle also. I think if I ever have a band, I would call it the Swinging Dinghys! A band by that name might even land a gig with Jimmy Buffet! Make sure the dinghy is all the way up to eliminate any extra force and stress that can be caused by a swinging dinghy. It may be a good idea to have an extra strap or two to tightly secure the dinghy to the davit or to the boat when sailing to keep if from moving. Rachet straps are a good idea for long passages. Remember a swinging dinghy can jeopardize the davit system (and your dinghy).
Man Overboard!
I have read about this happening to more than one person on the forums. The dinghy line comes loose and someone reaches out to pull the line tight just as a rogue wave hits the boat at a weird angle. In a split second, the person slips (or flips) overboard – hopefully noticed by someone onboard. A couple of points. Make sure you alert your captain and crew before attempting a fix so they are alert to what you are doing. If you are on a passage or in rough seas, it’s a good idea to have a safety line and/or PFD (i.e. life jacket) with EPIRB (beacon) so you can be found if you do go overboard.
Extra Padding
Depending on the davit system and type of catamaran, you may need to add padding on the davit to protect the dinghy when up and secure. The constant rubbing that occurs especially on long passages or crossings or in rough and choppy seas can harm your dinghy.
Custom Davit Systems
The davit system described in the above paragraph is one type, but there are many other types by OEM and custom aftermarket davit manufacturers. Many catamaran manufacturers use a davit system where the entire davit system (the stainless steel arms or frame) drops down towards the water. In this case, you clip each dinghy lines to the davit and lift the entire davit with one line through the winch. Both the front of the dinghy and rear of the dinghy and davit frame lifts at the same time.
Practical Davit Considerations
In addition to making sure the davit system is engineered to handle the weight of the dinghy (both actual and in motion) with consideration for the weight of the outboard motor, there are some other important things to look at.
First, make sure the dinghy fits the davit or the davit fits the dinghy. If not sized correctly, the motor may hit and rub on the davit. Next, consider how you are going to clip the dinghy to the davit. Will you be able to secure it in choppy seas? If you upgrade your dinghy, will your davits hold it. Very important to know before installing new davits and/or before buying a new dinghy. Davits are costly and so is a dinghy.
Catamaran Dinghy Davit Summary
Most catamaran owners will spend a considerable amount of time in their dinghy. It is a critical part of the catamaran sailing experience. It is therefore not only extremely important to have a dinghy that will fulfill your needs, but also to have a convenient way to store it. If you have the budget, invest in the best davit system you can buy as it will take away one challenge that comes with life on the high seas.
See you sailing!