The Ideal Sail Plan for the Lagoon 42 Catamaran

Note: This article assumes a good understanding of downwind and low wind speed sails. If you are relatively new, follow this link to our article on downwind sails first.

Update: This article was updated in January of 2023 after doing an Atlantic crossing and re-considering what we want in our ideal sail plan.

We finally decided on a sail plan for our circumnavigation! We worked with the UK Sails loft in NYC for a while, and we recently landed on a final plan. This article explains the factors we considered during the process and why this plan was ideal for us.

We should start by saying that, like boats, sail inventories are compromises. Like boats, the ideal sail plan for one person can be a horrible idea for a different one. The sail inventory below is our ideal sail plan based on our priorities, sailing style, and goals. Our inventory is likely the wrong sail plan for many. In fact, this is not what I would recommend when I help new Lagoon 42 owners decide on their sail inventory. So yes, there are many alternatives to this inventory that will work for most cruisers and catamaran owners. The goal here is not to convenience anyone that this is the way to go but to highlight the issues that sailors should consider when deciding on their sail inventory.

Our sail inventory reflects a preference for speed over comfort and a willingness to make frequent sail changes to optimize performance. Given these preferences, our inventory is larger and more specialized than the inventory of a cruising couple that prioritizes comfort and the simplicity of all-around sails.

Update: Since I wrote the sentence above, my thinking about what we want has changed significantly. Specifically, the Atlantic made me realize the limitations of specialized sails when sailing short-handed. It also made me realize that during a passage, the simplicity of a more all-arround Gennaker on a furller could actually mean faster speeds because it would be used more than more specialized sails on a dousing sock. More of this later.

We prioritize a large inventory to optimize speed for four main reasons. First, I am (Nestor) an avid racer and thus tend to enjoy getting the boat to sail as efficiently as possible. I know I will be frustrated during passages knowing the boat could be sailing at 1-2 knots faster if I had the right headsail for the conditions. Second, we like our long passages to be as short as possible. The right specialized sails can save us 2-3 days on an Atlantic or Pacific crossing compared to all-around sails. Those are 2-3 extra days that we will be able to enjoy safely and comfortably at anchor. Third, the right sails will allow us to sail in a much wider range of wind speeds and angles, drastically cutting down on motoring and diesel costs. So over time, this sail inventory will pay for itself (at least that’s what I tell myself!). And finally, having a large sail inventory can make us safer. The safety benefits are numerous, including redundancy on sails in case of sail damage, the ability to sail to safety upwind in conditions where otherwise you would have to depend on functioning engines, and the ability to get to anchor in the daytime while slower boats may get caught out in the dark.

Update: Everything I said in the previous paragraph is still true, but my thinking about what inventory will achieve those goals has changed.

Our original wish list

In considering our sail inventory, we wanted enough headsails to cover most wind angles and wind speeds at optimal performance. Here is the initial wish list we discussed with the sailmakers:

A jib with clew board.
A square-top main.
A true flat code zero. Most “code zeros” or screechers marketed for catamarans are all-around upwind and mid-wind sails covering 60-110AWA. These are great sails when you have a limited inventory, but they are not ideal because you sacrifice upwind performance to broaden the mid-wind range. Instead, we wanted to true flat code zero with a mid-girth of 55 to 60% that can perform well in 50-90 AWA.
A large true A2. We did not want a cruising spinnaker with a wide AWA range (e.g., 90-160) and speeds (up to 20 knots). These sails are great, but they sacrifice downwind and low-wind performance to fly in mid-AWAs. They are also smaller than traditional A2s. So we wanted a more specialized large A2 for sailing 130-160AWA at low wind speeds.
- Update: It is still true that we want an A2, but it is no longer true that we don’t want a cruising spinnaker. We want both, which I explain below.
A small S4 or S5. In most conditions, when sailing to a dead-down-wind destination, the Lagoon 42 will sail fastest when jibing at 160AWA as opposed to sailing directly to the destination. However, when the apparent wind speeds are above 20, the benefit of jibing disappears and sailing dead-down-wind is the faster point of sail. However, you can’t sail dead-down-wind in 20knots AWS with the A2 (or a cruising spinnaker). For that, you need a small and strong symmetrical spinnaker that you can fly square from both bows. Enter the S4-S5.
- Update: This is still true, but the likelihood that we would be flying an S4 in 25knots AWS, especially at night, when it’s just the two of us is unrealistic. If we had a larger crew of experienced sailors, I would get the S5, but given our plans, we would most likely sail with the jib on a barber hauler when the wind picks up and we are going downwind.
Extra A3. We did not initially consider an A3, but the team at UK sails highlighted a gap we had between the code zero and the A2. Because we specialized the code zero for close reaching and the A2 for deep-running, we ended up with a gap for sailing mid angles 80-130 in light to moderate winds. So we are considering adding an A3.
- Update: The A3 will be replaced by a furlling Gennaker that will also cover these same angles but maybe not in such high winds.

Our final inventory

White Sails

Main Sail
AWS: 0-40. AWA 45-160. Material: Hydranet. Size: 59sm.
Our main sail will be a 59sqm square top hydranet sail. This is pretty similar to the standard square top that many owners have, with the difference being hydranet. This is an expensive but bulletproof material that has some significant benefits over dacron, including its ability to hold its shape for many more years, its lower weight, and its greater durability.

Jib
AWS: 18-40. AWA: 45-160. Material: Hydranet. Size: 36sm.
Our new jib will be different from the standard Lagoon 42 jib in that it will include a clew board which will allow us to adjust the leech tension much better. A clew board is a must-have for a self-tacking jib if one wants to adjust the sail twist in varying conditions. It is surprising that the standard sail did not come with one. You will notice that our jib will be built to fly primarily in 18-40AWS. This means it can be stronger than the standard jib as it will not be expected to fly in low winds. The rest of the sail inventory will cover the lower wind speeds.

Downwind Sails

Asymmetrical 2 (A2)
AWS: 3-15. AWA: 130-160. Material: Superkote 90. 1.10oz. Size: 160sm.
The A2 is a downwind asymmetric spinnaker designed for winds under 15knots. It is quite large at 160sqmt and relatively light at 1.10oz but it is heavier than racing A2s of the same size to increase durability. This will be our most commonly used downwind sail in very low winds.

Furling Gennaker (UPDATED)
AWS 10-25. AWA 75-160. Material: Superkote 150/200. 2.2oz. Size: 130sm.
This is the most critical change to our original inventory. I realized during the Atlantic crossing that having a furling cruising spinnaker that can fly in 10-25AWS and 75-160AWA was critical for short-handed crews. I explained some of the issues in the Atlantic crossing article, but here is the issue. When short-handed, I don’t feel it is prudent to fly a dousing spinnaker at night, especially when the wind is borderline too high or when squalls are expected. Consequently, if all we had was a dousing spinnaker, we would be taking it down at night and significantly slowing down our average speed. In contrast, with a furling Gennaker, we can leave it out overnight as one could furl it as needed even when one-handed. This increases the time the spinnaker will be up and thus increases our average speeds. Furling Gennakers are game-changers for two-handed crews.

Upwind Sails

Code-Zero
AWS: 3-15. AWA: 45-90. Material: CZ30 Radial Laminate 55% Mid Girth. Size: 80sm.
Our new code zero is a very flat sail designed to fly in as low as 3knots. This sail is not an all-around gennaker or screecher as it is too flat to go fly any deeper than 90 degrees. However, it will fly upwind much better than a traditional cruising screecher or code-D/G type of sails.

UPDATE: We are changing our code zero to be able to fly in lighter winds at the cost of being able to fly in stronger winds (e.g., 15-18AWS). Why? Because the L42 is not able to keep up with this sail! What do I mean by that?

Why you should not fly the code zero in 15knots of wind speed: The issue is that as the wind increases, the AWA moves forward quite rapidly, which also increases the AWS. You then have to immediately bear away to keep both AWA and AWS manageable. The problem is that in winds above 15knots true, you will be forced to sail at 80-90AWA, which essentially means you are not going upwind at all!

Say, for example, that you are sailing in 12knots true at 55AWA with the code zero. In this case, you will be sailing around 5-6knots of speed. Your TWA is around 70TWA and your AWS is about 15knots. So you are going upwind but barely and the AWS is pushing the capacity of the code zero. Let’s say now that the wind speed increases to 15TWS. Two things happen. First, your boat speed will increase to 7 knots and your AWS will increase to 18+knots, at the safe limit for the code zero. Second, the apparent wind will move forward into the 40s, collapsing the code zero. The only immediate solution will be to bare away to decrease the apparent wind speed and bring the apparent wind angle back into the 50s. The problem is that to accomplish this, your true wind angle will need to be close to 90! If you don’t pay attention to this, you will sail for hours away from your destination, not going upwind at all. In this case, you are much better off taking the code zero down and using the jib, which will allow you to point much higher. For this reason, we won’t use the code zero in 15 knots when upwind so we rather be designed to maximize performance at low wind speeds.
Our final sail plan on a polar figure: