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Procedures

Sailing Basics

This page describes the basics of sailing. Much of the information on this page applies to sailboats generally, but some of the information – particularly the description of how the sails are rigged – is specific to the type of boat that Northern Light is, a Santana 35.

If you're not familiar with some of the terms on this page, look them up on the Glossary page.

Sails

When sailing upwind ("to weather"), the boat uses two sails: a main sail and a jib. Wind flows on both sides of the sails, which makes the sails act like airplane wings, pulling the boat forward and laterally. As the boat moves, water flows around the keel, which makes the keel act like an airplane wing as well, pulling the boat forward and laterally. The lateral force generated by the keel is in the opposite direction of the lateral force generated by the sails. The lateral force from the keel thus cancels out the lateral force from the sails; that leaves only the forward force, which pulls the boat forward (upwind). For a visualization of the “lift” forces that enable a sailboat to sail into the wind, see The Physics of Sailing, a 10-minute video from KQED.

When sailing downwind ("to lee"), the boat also uses two sails: a main sail and a spinnaker. In this direction, the sails act like parachutes rather than airplane wings – they fill with wind coming from behind the boat and drag the boat forward (downwind). The spinnaker is difficult to control because it has two free corners (corners that are not attached to something solid like the mast, boom, or forestay). Thus, if there are not enough crew members to help fly the spinnaker, or if the wind is very strong, the boat may sail downwind using a jib instead of a spinnaker.

When sailing perpendicular to the wind ("reaching"), the boat uses a main sail, and it may use either a jib or a spinnaker. In some situations the boat may use all three sails – a main sail, a jib, and a spinnaker. In this direction the sails act like airplane wings, and it is important for the crew to trim them (adjust their angle relative to the direction of the wind) so that the wind flows smoothly on both sides of each sail.

Position of Sails

The sails are always on the leeward (downwind) side of the boat, since that's the direction in which the wind pushes them. Thus:

  • If the wind is coming over the port side, the boat is said to be on a port tack, and the sails are on the starboard side.
  • If the wind is coming over the starboard side, the boat is said to be on a starboard tack, and the sails are on the port side.

Figure 1 below shows the position of the sails on a port tack and a starboard tack:

  Port Tack Starboard Tack
Sailing
to Weather
position of sails before a tack position of sails after a tack
Sailing
to Lee
position of sails before a jibe position of sails after a jibe
Figure 1

For optimal speed, sails need to be trimmed properly. To trim a sail means to adjust the angle of the sail relative to the direction of the wind so that air flows smoothly on both sides of the sail. When sailing to weather, the sails are brought in close to the centerline of the boat. As the boat turns and sails farther away from the direction of the wind, the sails are let out farther from the boat. The points-of-sail diagram below shows how the angle of the sails varies with the direction of the boat relative to the wind:

sail trim on each point of sail
Figure 2

Sailing Upwind ("To Weather")

Boats canít sail directly into the wind, but they can sail in an upwind direction by following a zig-zag course.

sailing to weather (upwind): tacking to the weather mark
Figure 3

Each time the boat changes direction at one of the corners of the zig-zag course, the boat is said to tack.

Each time the boat tacks:

  • the wind changes direction:
    • if the wind was coming over the starboard side before, it will come over the port side after
    • in other words, the windward rail before the tack becomes the leeward rail after the tack
  • the main and jib have to cross the boat – the sails move across the boat to the new leeward side

Itís important to complete each tack as fast as possible: The boat has no power and loses speed during a tack, and it takes a long time for an 8,000 lb. boat to build its momentum back up. The faster the crew brings in the jib, the faster the boat powers up and the less speed it loses.

Figure 4 below illustrates a tack in which the boat changes from a starboard tack to a port tack:

Before the Tack After the Tack
position of sails and lines before a tack
  • the boat is on a starboard tack
  • the working jib sheet is on the leeward (port) side
  • the working runner is on the windward (starboard) side
position of sails and lines after a tack
  • the wind is now coming from the other side (port)
  • the jib + main have both crossed over to the new leeward side (starboard)
  • the old lazy jib sheet on the starboard side has become the new working jib sheet
  • the old lazy runner on the port side has become the new working runner
Figure 4

Sailing Downwind ("To Lee")

When sailing downwind, boats typically use a spinnaker instead of a jib. The spinnaker acts like a parachute – it fills with wind and provides extra downwind speed. The spinnaker is raised immediately after rounding the weather mark, and lowered before (or while) rounding the leeward mark.

Boats can sail directly downwind, but for a number of reasons (currents, other boats, etc.), a boat may want to sail a zig-zag course:

sailing to lee (downwind): jibing to the leeward mark
Figure 5

Each time the boat changes direction at one of the corners of the zig-zag course, the boat is said to jibe.

Note the difference in terms:

  • When sailing upwind, changing from port tack to starboard tack (and vice versa) is called tacking.
  • When sailing downwind, changing from port tack to starboard tack (and vice versa) is called jibing.

Each time the boat jibes:

  • the wind changes direction:
    • if the wind was coming over the port side before, it will come over the starboard side after
    • in other words, the windward rail before the jibe becomes the leeward rail after the jibe
  • the main sail moves across the boat to the new leeward side
  • the spinnaker itself doesn't move very much, but the spinnaker pole moves across the boat, so that it can hold up the spinnaker tack (corner) on the new windward side

Figure 6 below illustrates a jibe in which the boat changes from a port tack to a starboard tack:

Before the Jibe After the Jibe
position of sails and lines before a jibe
  • the boat is on a port tack
  • the spinnaker pole is on the windward (port) side
  • the working afterguy is on the windward (port) side
  • the working spinnaker sheet is on the leeward (starboard) side
position of sails and lines after a jibe
  • the wind is now coming from the other side (starboard)
  • the main sail has crossed over to the new leeward side (port)
  • the spinnaker pole has crossed over to the new windward side (starboard)
  • the old lazy afterguy on the starboard side has become the new working afterguy
  • the old lazy spinnaker sheet on the port side has become the new working spinnaker sheet
Figure 6

Working with the Main

Using the Main

The main sail is used throughout the entire race. The main sail is only raised once (when we leave the dock), and lowered once (when we return to the dock).

Controlling the Main

The main sail is relatively easy to control. The sail is trimmed by moving the traveller windward or leeward, and by bringing the main sheet in or letting it out. The traveller and the main sheet are attached to the boom; when those lines are brought in or let out, they rotate the boom around the mast, and thus change the angle of the main sail.

The proper trim for the main sail depends on the boat's point of sail (see Figure 2). When the boat is sailing close-hauled, the main sail is brought in close to the centerline of the boat. As the boat bears away from the wind, the main sail is eased out farther from the boat. When the boat is on a broad reach or a run, the main sheet is let out all the way, and a crew member usually helps push the boom out so that the main sail is as far away from the boat as possible (nearly perpendicular to the boat).

What makes the main sail challenging is that it can be shaped in many different ways, and its shape significantly affects the speed of the boat. Here are some of the controls that can be used to shape the main sail:

  • the cunningham pulls opposite the halyard, and stretches the luff edge of the sail
  • the outhaul flattener pulls the clew toward the stern, and stretches the foot of the sail
  • the leech line tensions the leech edge of the sail
  • the boom vang pulls the boom down and flattens the sail
  • the running backstays pull the mast backward and to the side, and twist the sail

The crew member responsible for the main, called the mainsheet trimmer, looks at telltales (small pieces of tape attached to various places on the main sail) to see how the wind is flowing around the sail, and constantly adjusts the controls listed above so as to shape the sail for optimal wind flow and boat speed.

Attaching the Main

The main sail is attached as follows:

  • The main halyard pulls the head of the main sail to the top of the mast. The main halyard is located on the starboard side of the mast.
  • Slugs on the luff edge of the main slide into a track on the mast and hold the sail to the mast.
  • A clevis pin holds the tack in place at the mast.
  • The outhaul flattener attaches to the clew, and pulls the clew back toward the stern. The outhaul flattener runs through the boom; it comes out through a hole on the starboard side of the boom and is tied off around a cleat on the boom.

If the wind is very strong, the skipper may decide to reef the main. Reefing lowers the main sail by about a foot; this reduces the sail area exposed to the wind and diminishes the power generated by the sail. As illustrated in Figure 7, the main is reefed by lowering the halyard, attaching a cringle to a hook on the boom, and pulling a reefing line to draw the new clew toward the stern. The reefing line is tensioned with a winch and held in place by a clamp on the boom. The extra sail material along the foot of the main is held in place by reefing bungies that wrap around the boom.

reefing the main sail
Figure 7

Working with a Jib

Using the Jib

The jib is typically used on all legs in a race except for leeward (downwind) legs. The jib is lowered at the beginning of leeward legs, shortly after rounding the weather mark and hoisting the spinnaker. The jib is hoisted again at the end of leeward legs, shortly before the spinnaker is doused and the boat rounds the leeward mark.

Controlling the Jib

The jib is trimmed by jib sheets, which are attached to the jib clew. There are two jib sheets – one on the port side and one on the starboard side (see Figure 8 below). The jib sheet on the leeward (downwind) side of the boat is the working (active) jib sheet; this is the jib sheet used to trim the jib. The jib sheet on the windward side of the boat is the lazy jib sheet; this jib sheet is not active.

The grinders in the cockpit trim the jib by pulling the working jib sheet in or letting it out. The proper trim for the jib depends on the boat's point of sail (see Figure 2). When the boat is sailing close-hauled, the grinders pull the jib sheet in; this brings the jib close to the centerline of the boat. As the boat bears away from the wind, the grinders ease the jib sheet out, which lets the jib out farther from the boat. The grinders use a winch to bring in and let out the jib sheet, as the line is under too much stress to control by hand.

When the boat tacks, the grinders release the working jib sheet, and the jib crosses the boat to the new leeward side (see Figure 4). At this point, the jib sheets "switch:" The old lazy jib sheet becomes the new working jib sheet, and vice versa (see Figure 4). The new working jib sheet pulls the jib across the boat to the new leeward side. Itís important to complete each tack as fast as possible: The boat has no power and loses speed during a tack, and it takes a long time for an 8,000 lb. boat to build its momentum back up. The faster the crew brings in the jib on the new leeward side, the faster the boat powers up and the less speed it loses.

Two things typically hold up a tack:

  • lazy jib sheet: As the jib crosses the boat to the new leeward side, the new lazy jib sheet occasionally gets stuck on something (e.g., the bowline knot that ties the jib sheet to the jib may get caught on a shroud or on the mast; the jib sheet may get fouled up going into a block; or someone may stand or sit on the jib sheet). When this happens, someone usually yells "lazy!," and the crew must figure out what's holding up the lazy jib sheet and free it up as quickly as possible – the jib can't cross to the leeward side until the lazy jib sheet is freed up.
  • skirt: As the grinders bring in the jib on the new leeward side, the foot of the jib usually gets caught on a stanchion outside the lifelines. This prevents the grinders from bringing the jib in to its proper trim, and they start yelling "skirt!" The foredeck crew must lift the foot of the jib over the stanchion and put the foot inside the lifelines, so that the grinders can finish bringing in the jib and the boat can complete the tack.

A tack may also be held up if the jib sheets are not routed properly. The jib sheets must always run on top of the spinnaker pole and in front of the topping lift (see Figure 10 below). If the jib sheets are not routed this way, the spinnaker pole or the topping lift will block the jib and prevent it from moving across the boat. Problems typically occur after the boat rounds the leeward mark – for example, the jib sheets may slip under the spinnaker pole when the pole is lowered, or the jib sheets may get stuck in the spinnaker after the spinnaker is doused (lowered). If we try to tack and something holds up the tack, we will usually tack back to our original direction so that we can keep moving while the crew figures out and solve whatever problem is preventing us from tacking.

Attaching the Jib

The jib is attached as follows:

  • The tack attaches to a hook near the bow.
  • The jib sheets are tied to the clew using bowline knots.
    • The jib sheets must always run on top of the spinnaker pole and in front of the topping lift. If the jib sheets are not routed this way, the jib won't be able to cross the boat on a tack.
    • The jib sheets run through car blocks (fair leads) on tracks near the shrouds, through a second set of blocks, and into the cockpit.
  • The jib halyard pulls the head of the main sail to the top of the mast. The jib halyard is located on the port side of the mast.
  • The luff edge of the jib runs through a pre-feed hook that guides it into a track on the forestay. There are actually two parallel tracks on the forestay; the second track can be used to hoist a different jib (e.g., when the crew wants to switch to a smaller or larger jib).

When the jib is not in use (on leeward legs), the foredeck crew lowers the jib and straps it down to the foredeck with bungee cords. The crew typically prepares the jib for its next hoist by routing the luff through the pre-feed and raising the head a foot or so up the luff track, as shown in Figure 8:

attaching the jib
Figure 8

Working with a Spinnaker

Using the Spinnaker

The spinnaker is typically used on leeward (downwind) legs. The spinnaker is hoisted (raised) at the beginning of leeward legs, shortly after rounding the weather mark. The spinnaker is doused (lowered) at the end of leeward legs, shortly before (or while) rounding the leeward mark.

The spinnaker is the most difficult sail to control, because it has two free corners. If conditions are particularly difficult, or if there are not enough crew members, we may forego the spinnaker and sail downwind with a jib instead.

Controlling the Spinnaker

The spinnaker is an important sail because it serves as the primary horsepower of the boat on downwind legs. The spinnaker is also the hardest sail to control: Because it has two free corners, it requires a pole and 4 lines to hold in position. The lines are described below and shown in Figure 9:

  • The spinnaker pole holds up the spinnaker on the windward side of the boat. (Were it not for the pole, the wind would blow the whole spinnaker to the leeward side.) The inboard end of the pole is attached to the mast, and the outboard end of the pole is attached to the spinnaker tack (the free corner on the windward side of the boat). The pole itself is controlled by three lines: the topping lift, the foreguy, and the afterguy.
  • The topping lift pulls the pole up toward the sky.
  • The foreguy pulls the pole down toward the foredeck (think foreguy → foredeck).
  • The afterguy pulls the outboard end of the pole (the end that's attached to the spinnaker tack) back toward the stern, or lets the outboard end of the pole go forward toward the bow. To inflate the spinnaker optimally, the pole needs to be perpendicular to the wind. The afterguy adjusts the angle of the pole around the mast so that the pole is perpendicular to the wind.
  • The spinnaker sheet controls the spinnaker clew, which is the leeward (downwind) corner of the spinnaker. By pulling the spinnaker sheet in or letting it out, the grinders in the cockpit control how close the clew is to the boat, thereby adjusting the trim of the spinnaker (the angle of the spinnaker relative to the wind). The grinders constantly adjust the spinnaker sheet for optimal trim – their goal is to fill up the spinnaker with wind so that the luff (upwind edge) of the spinnaker "winks" (flaps lightly).
3D view of a spinnaker
Figure 9

Spinnaker Jibe

[TODO/START]

As you can see in Figure 9, the lower corners of the spinnaker (the tack and the clew) each has an afterguy and a spinnaker sheet attached to it. Only one line is active at a time – the other line is lazy (not working). The lazy lines become active (and vice versa) when the boat jibes.

Thus, in Figure 9:

  • The boat is on port tack (the wind is coming over the port side of the boat).
  • The spinnaker pole is on the port (upwind) side of the boat.
  • The port afterguy is working (active). The starboard afterguy is lazy (not active).
  • The port spinnaker sheet is lazy (not active). The starboard spinnaker sheet is working (active).

When the boat in Figure 9 jibes, the wind crosses over to the starboard side. When this happens, the lazy lines become active, and the active lines become lazy. After the jibe:

  • The boat is on starboard tack (the wind will be coming over the starboard side of the boat).
  • The spinnaker pole has crossed the boat to the starboard side (the new upwind side).
  • The port afterguy is lazy. The starboard afterguy is working.
  • The port spinnaker sheet is working. The starboard spinnaker sheet is lazy.

For a bird's eye view of what happens during a jibe, see Figure 6.

Spinnaker Douse

[TODO]
Attaching the Spinnaker
[TODO]
spinnaker pole
Figure 10
attaching a spinnaker
Figure 11
attaching a spinnaker
Figure 12
Packing the Spinnaker

At the end of a downwind leg, the spinnaker is doused (lowered), and stuffed through the hatch on the deck into the sewer below. A crew member then packs the spinnaker back into a turtle (storage bag). The spinnaker needs to be packed carefully, so that when it is hoisted on the next downwind leg, it comes out of the turtle without any twists. Think of it like a parachute – when you pull the ripcord, you want the chute to come out of the bag cleanly and to fill up with wind as soon as possible.

When the spinnaker is doused and stuffed through the hatch, it usually becomes twisted and contorted in all sorts of ways. The crew member who is packing the spinnaker needs to untangle these twists, and also to orient the spinnaker properly, with the head at the 12:00 o'clock position and the clews at the 4:00 o'clock and 8:00 o'clock positions (looking at the top of the turtle). The spinnaker needs to be oriented properly so that the foredeck crew can attach the correct lines to each corner (halyard → head; port afterguy and spinnaker sheet → port clew; starboard afterguy and sheet → starboard clew).

To straighten out the twists and make sure the spinnaker is packed in the correct orientation, the crew member who is packing the spinnaker uses color-coding on the edges of the spinnaker. This color-coding is shown in Figures 13 and 14, and described below:

colored edges on a spinnaker
Figure 13: Spinnaker Edges
colored edges on a spinnaker
Figure 14: Spinnaker Edges

The edges of the spinnaker are colored as follows:

  • The port edge is red.
  • The starboard edge is green (on the green, 1.5 oz. spinnaker) or blue (on the other two spinnakers).
  • The foot is white.

Thus, you can always tell which corner of the spinnaker is which by the color of the edges at that corner:

  • The head has a red edge on one side and a green or blue edge on the other side.
  • The port clew has a red edge on one side and a white edge on the other side.
  • The starboard clew has a green or blue edge on one side and a white edge on the other side.

Working with Lines

See the lines section of the glossary for a list of the different lines on the boat and the things you can do to a line.

See the knots section below for instructions on how to tie some frequently-used knots.

Working with Winches

Winches on Northern Light
  • On the foredeck:
    • There are 6 winches. Each winch is dedicated to a specific line:
      • the winch for the main halyard is on the starboard side
      • the winch for the jib halyard is on the port side
      • there are two winches for the spinnaker halyards (one port + one starboard)
      • there are two winches for the boom vang (one port + one starboard)
    • Read the label next to each winch to see what line the winch is for.
  • In the cockpit area:
    • There are 4 winches. These winches are shared (i.e., they trim different lines at different times):
      • the front winches are the primary winches
      • the rear winches are the secondary winches
    • When sailing to weather:
      • the primary winch is used for the jib sheet (on the leeward side)
      • the secondary winch is used for the runner (on the windward side)
    • When sailing to lee:
      • the primary winch is used for the afterguy (on the windward side)
      • the secondary winch is used for the spinnaker sheet (on the leeward side)
  • Figure 15 below shows the 10 winches on Northern Light and the lines that the winches are used for:
winches on a Santana 35
Figure 15
How to Use the Winches
  1. Wrap the line you want to pull around the correct winch.
    • See Figure 10 above for the correct winch to use for each line.
    • Always wrap lines clockwise around a winch.
    • Start with one wrap around the winch.
      • If the line is under a lot of stress, you may want to wrap the line multiple times (3 or 4 times) around the winch, but beware that having multiple wraps increases the chance of getting an override on the winch.
  2. Pull the line by hand.
    • Use LONG, HARD motions to pull the line quickly.
    • Pull the line UP slightly (toward the sky) rather than horizontally or down towards the deck. Pulling the line up reduces the chance of an override.
    • If you get an override (i.e., if the line crosses over itself on the winch), you need to clear the override (uncross the line) before you continue pulling it. See the tips section below for instructions on how to remove an override.
  3. When it becomes too hard to pull the line by hand, add a couple of wraps around the winch, and use a winch handle to turn the winch. This is called "grinding."
    • Most of the winches on Northern Light are dual speed:
      • Turn the winch handle clockwise (fast speed) to trim a line quickly.
      • Turn the winch handle counter-clockwise (slow speed) when the it becomes too hard to turn the winch handle clockwise.
    • The only winches that are single speed are the boom vang winches – you must turn the winch handle clockwise to put on the boom vang.
    • Ask another crew member to tail for you (pull the tail end of the line) as you grind.
  4. When you're finished pulling the line, cleat it off.
    • Wrap the line clockwise around the winch as you bring the tail end toward the cleat. In other words, given a choice between adding a wrap and removing a wrap to bring the tail end of the line to the cleat, choose to add a wrap.
    • On the foredeck, use a perfect cleat to tie the line off around a cleat.
    • In the cockpit, just wrap the line around the cleat and jam it in (the cleats in the cockpit are jam cleats).
    • After you have cleated off a line, clean up the tail end – e.g., stuff the tail end down the companionway so that it's out of the way and does not foul up any other lines.

Tips:

  • Avoiding an override:
    • When raising a halyard, the tailer MUST keep up with the jumper – use LONG, HARD motions to pull the halyard quickly.
    • To minimize the chance of getting an override, use fewer wraps around the winch. For example, use only one wrap around the winch while the jumper is still jumping, and add a couple of wraps before grinding.
  • Removing an override:
    • First, try unwrapping the line by hand – just unwind the line from the winch counter-clockwise.
    • If you can't remove the override by hand, unwind as much of the line as you can, then wrap the tail end of the line around a second winch (clockwise, as normal), and grind the second winch until the override is removed.
  • Never put winch handles down on the deck – they will fall into the water. Winch handles are stored in holders on the mast and in the cockpit. Always put winch handles back in their holder when you are done with them.
  • Some people recommend grabbing lines with palms down and thumbs toward you – that way your thumbs can't get yanked into a winch if the sail/line overpowers you.

Knots

Knots are key to sailing and racing well. It is crucial to be able to tie the correct knot in each situation. At a minimum, crew members should know how to tie the following knots:

  • slip knot
  • perfect cleat
  • bowline knot
  • stopper knot (e.g., double overhand knot)
  • Siberian hitch
  • reef knot
  • two half hitches

The table below has links to instructions for how to tie these knots, as well as a number of other useful knots. The important knots are highlighted with a colored background. Please practice these knots so that you can tie them quickly when you need to. Rod has a few lengths of practice rope on the boat that you can borrow if you'd like to practice at home. You can also buy your own practice rope at stores like REI and West Marine – a good size for practicing knots is about 6 feet of rope with a 7 millimeter diameter. For more information, check out John's favorite knot web sites:

Knot Picture Notes
slip knot
  • this knot is also called a slipped overhand knot
  • how to tie: slip knot
  • important: don't confuse with the simple noose
  • sample uses:
    • tying sail ties around the mainsail
    • closing off the jib “sausage bags”
    • securing the spinnaker sheets and afterguys near the blocks (note: the Siberian hitch is a better knot to use for this purpose, as it's easier to undo)
perfect cleat
  • this knot is also called a cleat hitch
  • how to tie: perfect cleat
  • use: securing the end of a line around a cleat
bowline
knot
double
overhand
knot
  • this knot is a type of stopper knot
  • how to tie: double overhand knot
  • sample use: preventing the jib sheets from running out of the blocks
Siberian
hitch
reef
knot
  • this knot is also called a square knot
  • how to tie: reef knot
  • sample uses:
    • tying the reefing lines around the mainsail
    • can also be used in an emergency to tie two lines of similar size together, e.g. extending the length of a broken line
two half-hitches
  • how to tie: two half-hitches
  • sample use: tying a line quickly to an object, when force or load is not a concern (e.g. tying off the ends of the cords that are used to pull the halyards inside the mast when unrigging the boat)
round turn and two half-hitches
figure eight knot
  • this knot is also called a flemish knot
  • this stopper knot is an alternative to the double overhand knot
  • how to tie: figure eight knot
  • sample use: preventing the jib sheets from running out of the blocks
constrictor
knot
highwayman's hitch
rolling hitch
  • this knot is also called a tautline or midshipman's hitch
  • how to tie:
  • uses:
    • attaching a line (usually smaller) to another (usually larger) line or pole when the line of pull is almost parallel
    • creating a loop with a slide and grip knot that can be readily adjusted by hand, but squeezes and holds firm under a load
grapple hitch
  • this knot is a type of adjustable grip hitch, like the tautline hitch, that is more secure than a bowline knot (although not meant to replace a bowline, unless a slip knot is acceptable) or buntline hitch
  • how to tie: grapple hitch
  • sample use: tying off bungee cords
overhand bend
  • how to tie: overhand bend
  • sample use: temporarily join the port and starboard jib sheets when they aren't attached to the jib clew
sheet bend
zeppelin bend
  • this knot, also called a rosendahl bend, may be the best way there is to connect two lines – claims are that it's secure, never jams, and is incredibly easy to untie
  • how to tie: zeppelin bend
  • sample use: joining bungee cords