Weather Helm and Genoas

The concept of sail balance is pretty easy to grasp. Powering up the headsails will produce lee helm as it moves the Center of Effort (CE) forward. Powering up the mainsail will produce weather helm as it moves the CE aft. When the forces of the main and headsails equal each other, the CE will align with the Center of Lateral Resistance (CLR) and will sail straight.  

If you suffer from weather helm, all you need to do is add more headsail area and/or reduce mainsail area, as this will move the CE forward and reduce the weather helm felt by the captain. A genoa is a massive headsail which should give you plenty of leeward force and help balance out the yacht, but this may not be the case. 

As you sail and feel weather helm, you might try reefing the main and letting out more of the genoa from the roller furler. Somehow, nothing seems to have changed! The weather helm is still present. Letting out more genoa doesn't seem to help any more either, as the problem continues to exist! 

Why would such a large headsail fail to balance out the sailplan? The answer is simple: a genoa is a jib that extends beyond the headsail triangle and continues aft of the mast. While the headsail is set forward of the mast, the portion that exists aft of the mast will move the CE aft. The larger the genoa, the more this effect increases.  

This is why you will see people beating to windward under genoa alone, with no mainsail, and they will be sailing along at a good pace! The large headsail, especially with genoas that are 150% or larger, will create enough weather helm by themselves that they are able to power your yacht to weather. Adding a mainsail to the combination only exasperates the situation, adding even more CE aft which will create even more weather helm. 

If you have a genoa and find your self struggling with weather helm, consider roller reefing your genoa before you try to reef your mainsail. Reefing your genoa will actually move the sail area forward and also move your CE forward which will help reduce weather helm and balance your sails. 

What is Sail Balance

A perfectly balanced yacht is a dream that most long for. The thought of setting the sails with the rudder straight and locking the helm as the yacht sails herself through the seas towards their intended destination.

Then reality comes when you set the sails and find that it keeps turning to windward and you end up dragging the rudder to leeward as you fight the forces and try to keep on course. If the winds build up too much, you will soon feel overpowered as your arms turn into spaghetti noodles with exhaustion and your yacht rounds up into the wind. 

The fight is over, and the forces of wind and balance have won! But why does this happen? 

Weather helm is caused by two forces: wind force and hydrodynamic force. The wind forces on the sails add up into what is referred to as the "Center of Effort" which is none other than the geometric center of each sail, and then the combination of each sails Center of Effort (also referred to as CE) to give you the yachts CE. 

The hydrodynamic forces are the same concept, being the geometric center of the underwater profile when viewed as a silhouette. This is called the "Center of Lateral Resistance" and is also referred to as the CLR. 

CE can be moved around by changing the sails that are flying and adjusting the trim of the sails, but CLR does not change.

Basically, you have two variables that control balance, one is fixed, the other is in your hands to control!  

If the CE is aft of the CLR, the yacht will want to turn to windward. This is the case if too much sail is being flown aft and not enough sail is being flown forward. 

If the CE is forward of the CLR, the opposite will occur and the yacht will want to turn downwind. This is the case when flying a giant spinnaker, as the large sail area forward will pull the yacht downwind and will not allow the yacht to travel upwind. 

Balance occurs when the CE and CLR are in the same position fore-aft. When this occurs, the yacht will sail straight with no desire to turn, requiring no input from the rudder to keep it on track. 

Meeting DinghyDreams

While in Oriental, NC, we met Emily who was solo cruising on an Ariel 26. Now, Emily was different from other cruisers we have met so far for a few reasons: ​

1. She is a solo female cruiser.​

2. She does her own repair work.​

The first point really stood out to Maddie and me. There seems to be a typical group of people who are cruising, and they fall neatly into a few categories. You have the retired couple who worked their whole life with the dream of cruising and is now doing it in retirement, and then you have the younger crowd that seems to be dominated by men. ​

The younger crowd seems to made up of guys in their early 20s who want to go explore the world and find themselves! They gather up what they can and set out on a boat around 30 feet in length or less and head off cruising. They will work their way along as they travel and see the world from a perspective that most only dream of!

Some of these young men are accompanied by a wife or girl friend, but if they are alone, they are all male. Emily breaks this stereotype by being a solo female cruiser. I am not saying that women can't or shouldn't, (in fact I think everyone should!)​ but just that you rarely encounter this situation.

To make it even more unique, Emily does her own repair work. She knows the setup of her boat and everything that makes it tick! If something starts to fail, she knows what the problem is and how to fix it; then when she makes her next port, she fixes it herself!​

Emily maintains a blog as well and I highly encourage you to check it out! ​

Http://www.dinghydreams.com​

She is currently heading south towards warmer waters (we all are this time of year) where she will continue to replace her aged standing rigging as she works along the way.​

Cruising is an amazing vantage point on the world, and it shouldn't be limited to just crazy young guys and elderly retired couples. Everyone who dreams of sailing off into the distance to see what's out there should certainly give it a go! If you have trouble along the way, there will always be other friendly cruisers around who will be there to lend a hand.​

Fair winds Emily!​

Motor Sailing with an Electric Motor and Generator

Electric motors boast many advantages over diesel motors. They are quiet, clean, and virtually maintenance free! They run when you need them to and stand idly by when you don't. When sailing along with speed, the spinning propeller actually generates electricity for you to recharge your battery banks.

The one advantage that a diesel motor has over an electric is range. There is nothing quit as energy dense as fossil fuel on a yacht. A small volume of liquid will power your yacht for hours and miles without a single complaint. If you run low on this magical wonder juice, all you need to do is pull up to a fuel dock and pour some more into your fuel tank! This is a quick process that takes only minutes to complete. 

Electric motors carry their energy source inside of batteries which will gladly give up their power, but seem to resist accepting power in return. When a fuel tank is empty, all you need to do is pour more fuel in! When a battery is empty, you will need to force power back into it with considerable effort, a process that can take many hours to complete. 

If you plan on motoring fast and far for long periods of time, a fossil fuel motor would be your best choice. If you plan on using your motor for short spurts of power, followed by days of sailing, an electric motor might be a better fit for you.  

Electricity stored in batteries is odorless and clean. It doesn't need to be run through filters or polishers to keep it clean, instead it simply sits waiting for you to call on it. 

Now, what if you find that an electric motor would be your dream power source in your yacht, but you do plan on the occasional motoring. You could solve this dilemma with a simple compromise. A generator will grant you the ease of fossil fuels and the convenience of electric propulsion. The generator powers your battery charger which feeds the battery bank and motor. 

Now, your range and speed will be decided based on your charging capabilities. Your generator will only provide as much power as the charger can put out. If you have a 5 amp charger, then you will only be able to motor along at 5 amps with the range of your fuel supply. If you are wondering, 5 amps is hardly moving and you might be better off to just drift with the tide! 

If you have more charging capability, say 25 amps, you would then be able to motor along at 25 amps (which is still slow, but you would be moving at around 3 knots) for as long as your fuel supply lasts. 

As you can see, the more charging you can produce, the more speed you can motor with. While you may feel limited by your charger, this should not be a concern. 

For example, say you have 15 amps of charging capability, which will motor you along at around 2 knots. You want to go 5 knots and are drawing 60 amps, you can simply throttle up to 60 amps and know that you are drawing 15 amps from the charger and 45 amps from the batteries. This will let you motor along for a few hours at this speed before you will need to slow down and run at a speed governed by the generator and charger. 

This might seem like it is limiting, but if you need to motor 20 miles, 5 knots will get you there in 4 hours. Once you are there, you can let the generator continue to run and recharge the battery banks once you have arrived with speed and ease. 

Generators give you a portable charging solution, adding greatly extended range to your electric propulsion setup. When coupled with solar panels as well, you will find that you will be able to motor along well enough to grant you the peace and tranquility you wanted every time you need that short burst of power. 

Masthead Fore-Aft Positioning

The position of the masthead in a fore-aft position to the mast step (also known as rake) is an important point of adjustment for sail handeling. If the masthead is too far forward, the boat will suffer from lee helm, the desire for the boat to turn downwind. If the masthead is too far aft, the opposite will occur and the yacht will suffer from weather helm, the desire for the boat to turn upwind. Somewhere in the middle of these two positions is the sweet spot where the forces will be equal and the yacht will sail straight and balanced.

For safety reasons, most yacht designers incorporate a little bit of weather helm into the yacht so that if you were to fall overboard, the yacht would eventually turn upwind and stall. This would theoretically allow you to swim back to your yacht and perform your own rescue. 

While the theory about masthead position is all well and good, it can be a bit daunting to perform in practice. When you stand on the deck, the mast just looks like it goes up. It is almost impossible to visualize if it is slightly forward or aft of its desired position. Even more compounded when the specifications call for the masthead to be raked 8 inches aft. 8 inches aft of what?! How can you tell where the masthead is way up there and then how are you supposed to position it 8 inches aft? 

There is a simple trick to this dilemma, and it involves gravity. 

A mast is supposed to be raked aft. This means that the front of the masthead will lie over the mast base and the rear of the masthead will hang aft of the entire spar. The main halyard exits the masthead on the aft side of the spar and is thus the perfect candidate for this exercise and measurement. By hanging a large jug of water, say around 1 gallon, by the main halyard, the halyard will transform into a plumbline which can be used to measure the position of the masthead relative to the step. 

If you have access to a drawing of your boat by its designer, it will usually tell you how many inches aft the mast should be raked. If you have this information, all you need to do is tighten the backstay while you loosen the headstay and move the masthead aft until the halyard (which is now a plumb line) marks the distance desired. 

The point that you will be measuring will be your gooseneck, which you can think of as "inch 0" since it attaches to the aft of the mast. Each inch aft of the gooseneck as you move down the boom will be your point of measurement.  

For example, if you need to position the masthead aft by 5 inches, you will simply adjust the headstay and backstay until your halyard crosses the boom 5 inches aft of the gooseneck. 

Having a designer tell you how to set everything up is wonderful, but what if you are not graced with that knowledge? There is a simple starting point that can point you in the right direction. 

In general, you want your masthead to sit just aft of the mast step. If you think of the spar as a tube in space, and you compress the tube vertically until it is nothing more than the oval at the bottom and the oval at the top on a flat plane; you would see the oval at the bottom (the mast step) sit right in front of the oval at the top (the masthead).  

What this means is a good starting point is to position the aft side of the masthead the distance aft of the gooseneck that the spar measures fore-aft. If you have a 4 inch spar, you will hang your halyard plumb line 4 inches aft of the gooseneck. If your spar is 12 inches fore-aft, then you will hang your halyard plumb line 12 inches aft of the gooseneck.  

This is obviously just a starting point and should be adjusted from there depending on how the balance of your yacht feels. If you find that you have too much lee helm, rake the mast further aft. If you find that you are struggling with weather helm, ease the masthead forward a bit. 

With tuning and practice, you will find the sweet spot that your mast likes to be for your given yacht and sailplan. Most importantly, when you find this sweet spot, measure it and write it down so that the next time you take your mast off, you will know exactly where to set it when you are recommisioned.