sailing thumbnail vertical double stripes
main title
 If you started off across the river or lake on a reach as we suggested for you initial sail, you will eventually reach a point where you must turn and head back. If the turn changes the wind from one side of the boat to the other, you will have tacked or jibed.It will be a TACK (also called coming about) if you turn the bow of the boat through the eye of the wind, and it will be a JIBE if you turn the stern through the eye of the wind.
jibing/tacking diagram Since the sail reacts quite differently to the two types of turns, it is of the utmost importance that you know which maneuver you are performing.

  In a small boat such as the Tech Dinghy, the tack is a safer maneuver so you should start with the tack rather than the jibe. The closest angle you can expect to sail toward the wind is a 45 angle, so to perform a tack you must turn a minimum of 90 to complete the tack.If you are going from a beam reach in one direction to a beam reach in the opposite direction, a 180 turn will be required. Since the sail will be luffing during most of the tack it is important the boat have good speed (relative to the given wind speed) through the water.If the sail is well out or luffing, trim the boom into the back corner of the hull if you can do so without causing excessive tipping to leeward. Ideally the sail should be trimmed as the turn into the tack is started, however, during the learning process it would be permissible to trim in first. Ease the tiller to leeward to start the tack, but keep your body weight to windward initially to avoid throwing the boat out of balance.

Watch the sail and when the boom starts toward you, duck under the boom and move toward the new windward side by standing momentarily and pivoting around facing the bow (it is important to be able to watch the luff of the sail and see just where your bow is pointing). Bring your hand holding the SHEET (the rope which controls the sail) behind your back to collect the tiller, letting the sheet slide through your hand and maintaining only enough pressure on the line to keep it from running out. Do not straighten the tiller until the sail stops luffing or until the boat swings further to some point you now wish to head for. Straightening the tiller before the sail stops luffing will leave the boat stuck IN IRONS (stopped headed into the wind). Failure to straighten the tiller after the tack will cause the boat to keep turning until it jibes.  After the tack, adjust your weight for good boat trim and take the sheet in the forward hand, and adjust the sail to assure it is properly trimmed for the course you have selected (so it is just on the verge of luffing). Jibing is the opposite of tacking, and as we said earlier, involves a turn that moves the stern through the eye of the wind. Unlike the tack, the sail will cross quickly to the new side without any luffing, and in a strong wind this sudden change of wind pressure from one side of the boat to the other can cause a capsize if precautions are not taken.

Also, unlike the tack, a large change of course is not necessary for a jibe to occur. If the boat is already sailing on a RUN (a course where the wind is at the stern) a change of course of a few degrees or a wind shift of a few degrees, can cause a jibe. jibe diagram

To perform a controlled jibe, move the tiller to windward (away from the sail) and immediately reach around behind your back with the forward hand to hold the tiller to windward. At the same time move your weight to the centerline of the boat again facing toward the bow. The maneuver of moving your weight can be done with you in a deep knee squat, thus keeping your head low and out of the way of the boom. As you become more confident, you can stand and duck at the appropriate time and be in a better position to move your weight to keep the boat level. In a larger, more stable boat you would trim the sail all the way in and ease it out again on the new leeward side to cushion the shock of the boom snapping from one side to the other.

 In a boat as small as the Tech, trimming the sail more than half way in may cause excessive tipping to leeward, however, it is desirable to trim the sail half way in so the wind can get behind the leech of the sail and force the sail across without your having to sail too much BY-THE-LEE (where the wind is striking the leeward side of the boat). You should watch the telltale on the stay to see when you are by-the-lee and watch the leech of the sail since it will fold toward you just before the boom is blown across. If it is quite windy, get the tiller back to the centerline of the boat as soon as you see the sail start to move across so you will not end your jibe on a beam reach and consequently be tipped excessively to leeward. Also ease out the sail as soon as it crosses the boat to prevent tipping. After the jibe, adjust your weight for good boat trim and also check your sail for proper trim.

boat tag  
  • Diagrams and Text courtesy of Sailing and the Tech Dinghy
  • Permission granted by: Harold "Hatch" Brown, MIT.
  • Black and white clipart were provided by
  • Created by: Nondini Naqui '02
  • Maintained by: Bonnie Dix
  • Date Created: 7/27/00
  • Last Modified: 8/9/00