Gybes: getting beyond the basics
We first covered gybe technique in this column way back in 2016. Thought it would be time to re-visit the subject with an eye towards getting beyond the basics of merely surviving the gybe (without wrapping the spinnaker around your headstay or wiping out). The art of gybing the asymmetrical spinnaker has gone through considerable refinement as more and more boats have adopted them and the symmetrical has slowly gone the way of the Dodo. Here are a couple of tricks to add to your arsenal which will help you not just execute them but will turn your gybes into boat-length gobbling weapons.
The late main gybe
For most displacement boats the emphasis in the gybe is on a slow smooth turn, good ease on the old sheet to get the sail past the headstay, and then pull like crazy on the new sheet. In the classic teaching of the gybe, the mainsail comes across as the stern swings through dead downwind, and the emphasis is getting the sail across under control. Pull the mainsheet in as you bear away. Have it near the centerline as the breeze is directly behind the boat, and then ease it out immediately on the new side. This is nice and safe but not necessarily fast.
The problem with the mainsail coming across basically at the same time as the spinnaker is that it blocks the air that the spinnaker needs to fill on the new side. What if we could help the refill by not letting the mainsail come across before the spinnaker was full on the new side? Voilà, the late main gybe. The trimmer, often with the help of one of the mid-boat crew grabbing the vang or the boom, holds the boom on the wrong side until the asymmetrical is across and filled in. When the mainsail comes across, it will be with authority! Oftentimes the mainsail trimmer will struggle to hold the boom against the pressure.
When the boom is released, the rest of the team has to be warned and needs to duck. Team members helping pull the new spinnaker sheet down and back are the most vulnerable. The mainsail trimmer also has to have fast hands. When the boom comes across, there will be a lot of slack in the sheet that needs to get pulled out before it wraps around a winch, tiller, wheel, or teammate. If you are quick, you can actually stop the sail in a slightly over-trimmed position and “pop” the battens into the correct orientation for the new tack, and ease to proper position for the angle. The big mainsails (square tops) found on most modern boats often have lots of stiff battens to support the roach, so they often need encouragement in lighter conditions.
A couple of caveats here: Boat size has a big impact on whether or not you can hold the boom long enough to help the spinnaker fill. On bigger boats this technique becomes impractical. Wind velocity is the second factor. Late main gybes are easy in light air, but the loads go up as the breeze increases. Eventually you will just not be strong enough. Then, it is time to change technique.
Priority main gybe
When it gets windy, holding the boom on the wrong side until the spinnaker fills is not only impossible, but it is also a bad idea if you want to keep the boat under control. In breeze, the mainsail needs to get across as soon as possible so that it doesn’t steer the boat. As the driver bears away, there is a critical moment when the mainsail starts to unload. This is the magic moment where it needs to get across the boat with authority. You will be able to get it trimmed in partially, but the last part will come across violently. You need to get just enough sheet to maintain some control and not get excess sheet wrapped around something as the sail comes across. Ease immediately and generously once the sail is on the new side.
A nice touch is to get the vang on hard going into the gybe, and release immediately once the sail is on the new side. This is not the time for a slow turn as you wait for the sail to come around and fill. The driver needs to be firm and committed with no hesitation in a priority main gybe. You don’t care if the spinnaker fills right away. In fact, it may be better if it doesn’t until the team is back in position aft and on the rail. Just make sure the asymmetrical gets across to the new side. Don’t worry if it is luffing. Priority main gybes are all about control in windy conditions.
“Blow-through” gybes
For boats that plane easily there is a totally different technique. Instead of floating the spinnaker out in front of the boat and rotating underneath until it fills on the new side, the spinnaker is over trimmed and allowed to back completely and is released. Pull the new sheet like crazy to refill the sail after it is let go. This only works on smaller boats where the spinnaker is of a reasonable size. The beauty of the blow-through gybe is that it is done so rapidly that the boat can stay up on a plane if done correctly. The technique also has the secondary advantage of allowing a quick gybe without telegraphing the fact. In one-design and close racing this can be an important tactical advantage when you want to avoid having a trailing boat gybe on top of your air. It can provide an escape route to clear air.
The technique is tricky and requires good coordination. A couple of keys: First, the turn is aggressive and requires absolutely no hesitation. Second, as the old spinnaker sheet is over trimmed and the sail is allowed to back, the clew must be pulled down hard or the top of the spinnaker will twist and prevent the sail from blowing through cleanly when the sheet is finally released. Third, we still don’t want the sail to go back through the fore triangle. It still has to go around the headstay so the jib must be tended during the gybe. Over-sheet the sail to act as a blocker to prevent the spinnaker from going through the fore triangle in the middle of the gybe and release almost completely (at least until the jib is luffing) as soon as the spinnaker is on the new side.
If you have the jib over-trimmed as you come out of the gybe, the spinnaker will not fill. You need a jib up for a blow-through gybe. This means it will be windier, since the jib is typically left up on most high-performance boats only in 12 knots and up. In light air the jib gets in the way and makes the spinnaker hard to fly. In top one-design classes such as the Melges 24 and 32 teams have mastered the art of the blow-through in conditions down to nine to 10 knots.
Exit angle
No matter what kind of gybe you are doing, the key is coming out at the right angle. This is essentially close to the same angle at which you went into the gybe. Over-rotate and the spinnaker will collapse, or if windy, you can broach and lose control. Under-rotate and the boat will wallow and come out underpowered. This kills acceleration. If you are doing the controlled smooth turn of the late main gybe, or the more aggressive turn required by the priority main or blow-through, exit angle is the key.
The squash
The last touch to add to your gybing arsenal is weight placement. As the sails fill on the new side and the boat hits the correct exit angle, things are going to load up. Just as it does, a coordinated crew movement to the high side (and aft if it is windier) will flatten the boat and turn the power surge into acceleration and boat speed. Coordination is key. The team needs to move together to have maximum effect. Often there is a designated weight caller to make sure the timing is right and to ensure that everyone moves together. Being a little quicker out of each gybe and maximizing acceleration turns into boat lengths down the course. It is also a tactical weapon when fighting to keep your air clear from an attacking boat.
For a great video (admittedly with somewhat dated sail technology but excellent illustration of technique), visit Quantum Sails YouTube channel and search for “blow-through” gybe.
By David Flynn of Quantum Sails
Questions? Email [email protected]
