Revision as of 07:29, 14 August 2009

This an outline of the training materials for using the catamaran at MIT. The intent is to develop the material here, then move it to the open courseware site for production.

General Principles

Explanations of:

• twin hulls versus monohull (wetted area, cross-sectional drag)
• weight of boat vs weight of crew

Explanation of sailing angles:

• broad reach is usually fastest sail angle
• closest to wind is 40 degrees?

Clothing

gloves. booties. harness (hook or ball). life jacket. wetsuit.

Rigging

get the dock very wet. putting the boat in the water. docking line. tying up to the dock in various wind directions. daggerboards. how to adjust the trapeze lengths. how to raise and secure the main sail. halyard shackle in small slot. outhaul. barber haulers. mast rotator. jib furler. rudder cams. main traveler. jib traveler. slight wrinkles in jib. mast angle versus sail angle to get main sail secured.

De-Rigging

docking line. daggerboards. furl jib. release main sail. roll main sail. shackles stay on boat. rudders up. rudder cams up. pulling the boat out of the water. drain hulls of any water. tie off main halyard to main traveler. mast angle versus sail angle to get sail down.

Sailing

weight matters. fore-aft depending on wind strength.

Tacking

roll tack as much as possible. back with jib if necessary. ease main sheet through the tack, tighten once wind is on other side of sails. reach around main sheet for tiller. do not move weight side to side too soon (but not too late or capsize!)

Gybing

do not throw crew off the boat. reach around main sheet for tiller, then do the gybe. help main sheet and traveler across. maintain control of main sheet and traveler lines.

Reaching

use the barber hauler. mast rotator should be loose. pull daggerboards for more speed. ease downhaul if appropriate. fore-aft weight depending on wind speed and hull angle. ideal roll angle is flat or the wild thing (leeward hull only). beam reach can easily lead to capsize if you lose track of boat/wind direction. keep main sail off spreaders.

Beating

tight mast rotator. keep bows in water, but not too far. do not over-tighten jib. tighten downhaul if appropriate. ideal roll angle is leeward hull only, windward hull just above the water surface (minimize wetted area). keep weight forward to improve sail angle. de-power sails by pinching, but beware unintentional tack, especially when on the wire.

Running

wing and wing is slow. almost always better to reach. keep main sail off spreaders (which leads you to reach rather than run).

Hiking and Trapping

use hiking straps when not enough wind for trapeze. to go out on the wire, pull trap to you, slide back off the boat until trap takes your weight, get legs under you. keep legs shoulder width or more apart. balance fore-aft just as important as in-out. pull on handle to come in. ensure that trap length is appropriate for body geometry and wind conditions. skipper out to the wire first, then crew. crew moves more in variable air. skipper and crew intertwined to reduce drag. managing the tiller extension. line management when at high roll angles. line management when crew and skipper are both trapped out. weight management when soloing.

Capsizing and Righting

do not fall/jump onto the mainsail. do not fall/jump onto the jib. do not stand on daggerboards. get righting line over top of hull as soon as possible to avoid turtling. need 250 pounds or more to right the boat. ease main sheet but do not release sheet or traveler. jib sheet should be tight. rotate boat so mast just about into wind, with wind coming under mast. grab dolphin striker as boat rights. how to avoid pitchpoling. when easing the main still results in capsizing. heading up too fast results in capsize. puffs when already at 40 degrees or more. how to unhook from trapeze when high roll angle.

Parts of the Boat

these are the boat parts and what they are used for:

• mast (aluminum and carbon)
• spreaders
• boom
• trampoline
• hulls
• bridle
• forestay
• main sail
• main sheet
• main traveler
• main battens
• downhaul
• outhaul
• mast rotator
• jib
• jib sheet
• jib traveler
• jib furler
• jib halyard
• jib sheet preventers (blue bungie, use of furling line)
• barber hauler
• trapeze handles
• trapeze retractors - skipper
• trapeze retractors - crew
• righting line
• righting line retractor
• daggerboards
• rudders (up, down)
• rudder cams
• rudder connecting rod
• extendable tiller
• drain plugs
• inspection portals
• storage pouch

Videos and Stills

this is a list of the videos and still images we need to illustrate the points above.

• still image or two for each of the boat parts
• video of tacking, no traps, illustrating the timing issues and rolling
• video of tacking, skipper and crew from trapeze to trapeze
• video of gybing, illustrating the timing issues
• video of crew during a tack (especially jib sheet management)
• video of a capsize, preferably from two viewing angles (windward and leeward)
• video of getting righting line ready for righting
• video of righting the boat
• video of putting rudders down
• video of putting sail up (closeup of top of mast and bottom of mast)
• video of trapping out/in - skipper
• video of trapping out/in - crew
• video of putting boat into water
• video of pulling boat from water
• pictures of mast rotator adjustment when beating and resulting sail shape
• pictures of mast rotator adjustment when reaching and resulting sail shape
• pictures of good/bad hull pitch angles
• pictures of good/bad hull roll angles
• pictures of good/bad skipper/crew positions (fore-aft/windward-leeward)
• pictures of good/bad sail shapes
• pictures of mainsail on shrouds (bad)
• pictures of good/bad jib trim

shoot the tacking and gybing videos from off the boat, also from on the boat? parts from on the boat?