Difference between revisions of "Lynx 16"
|Line 15:||Line 15:|
sailboats, motor boats, and human-powered vessels.
sailboats, motor boats, and human-powered vessels.
The aim of this page is to give detailed information on every aspect of the Lynx. Lynx16_Cheat_Sheet is a one page summary with just the essentials.
The aim of this page is to give detailed information on every aspect of the Lynx. Lynx16_Cheat_Sheetis a one page summary with just the essentials.
== Sailing in the Charles River Basin ==
== Sailing in the Charles River Basin ==
Revision as of 08:34, 19 April 2011
The MIT Sailing Pavilion has a new fleet of six 16-foot gaff-rigged boats built by Arey's Pond Boat Yard. The Lynx is a traditional Cape Cod catboat, with one mast at the front of the boat and one gaff rigged sail, meaning the sail is four-sided. The style is traditional for workboats off Cape Cod, Martha's Vinyard and Nantucket. Other catboats at MIT include the Tech Dinghy and the Laser, but the Lynx is the only one with a gaff rig. It is a great party boat because it holds six to eight people, is relatively stable, and has a distinctive style. This document describes how to rig and sail the Lynx as well as how to take it on trips to Boston Harbor.
Because of its distinctive rig, the Lynx is a very recognizable boat. As such, sailors should consider themselves ambassadors for MIT and practice good seamanship, following the rules for right-of-way with sailboats, motor boats, and human-powered vessels.
The aim of this page is to give detailed information on every aspect of the Lynx. [Lynx16_Cheat_Sheet] is a one page summary with just the essentials.
- 1 Sailing in the Charles River Basin
- 2 Harbor Trips
- 2.1 Before the Trip
- 2.2 Engine
- 2.3 Stepping the Mast
- 2.4 Checklists
- 2.5 Getting to the Harbor
- 2.6 Raising the Mast
- 2.7 Navigating in the Harbor
- 2.8 Docking at Spectacle Island
- 2.9 Returning Home
- 2.10 Contributors
Sailing in the Charles River Basin
When sailing in the Charles River Basin, all the Pavilion rules apply in terms of areas allowed to sail and recall signals. The Lynx's draft is shallow: 4'6" feet with the centerboard down, and 14" with the centerboard up, but it's still bad idea to run aground in Boston!
It's a good idea to keep some general guidelines in mind when sailing the Lynx. First, keep the lanes clear. Stow all backpacks and gear under the bench, so that crew can quickly move from the back to the front of the boat. Second, make sure the mainsheet and halyards are always running free; never tie them to themselves or stow them in a way that cannot be quickly released. (But never untie the stopper knots in these lines!) Be aware that the mainsheet sometimes gets caught on the traveler when tacking or gybing.
Rigging the Boat
The Lynx is a gaff-rigged boat, unlike MIT's other boats. A gaff-rigged boat has a second spar called the gaff, which lies parallel to the boom when the sail is down, and rises at an angle above the mast when the sail is up. This rig increases the size of the sail area the mast and boom can carry, with less heeling than a triangular sail, although it cannot sail as close to the wind.
To prepare the Lynx for sailing, first take off the sail cover, roll it up, and stow it under a bench. Take off the tiller-tamers, the lines holding the tiller stationary. Take out the boom crutch and stow it under the benches. Lower the centerboard all the way.
Make sure the mainsheet is not cleated or fouled. But never take the stopper knots off the end of the mainsheet! These are there to prevent the mainsheet from flying out of the boat, and to prevent the mainsail from gybing around the front of the boat.
To raise the sail, first note that the Lynx has not one, but two halyards, one to raise each end of the gaff. The end of the gaff closest to the mast is called the throat; the end farthest from the mast is called the peak. The corresponding halyards are called the throat halyard and the peak halyard. To raise the mainsail, pull both halyards up at about the same rate. Pull the throat halyard tight as high as it will go. Then raise the peak halyard until the sail is smooth. If the peak is too loose, there will be horizontal wrinkles in the sail; too tight, and the sail will have vertical wrinkles. Adjust it so that there is just a hint of a vertical wrinkle, as the lines will stretch once underway. Coil the halyards, laying the coils in opposite directions. Do not finish by tying the halyard to itself, as that might make it difficult to quickly lower the sail in an emergency. Instead, reach through the coil and pick up the line where it comes off the cam cleat, pull the loop back through the coil, and loop it over the horn cleat. Then if the halyard needs to be lowered in a hurry, it can be lifted off the cleat, dropped on the deck, and it is ready to go.
Make sure the lanes are clear in the boat: the fender should be wedged under the seat, and backpacks should be pushed under the benches. Then the crew can quickly reach the front of the boat in order to lower the sails or open the dry storage space.
When leaving the dock, pull the sail in to power up the boat and push the tiller towards the dock. It will probably be necessary to give the boat a large push to get it onto the correct tack. Make sure the centerboard is all the way down to make it turn as quickly as possible. Once the boat is away from the dock, stow the fender under the bench. Wedge it in place so it will not move while under way.
When casting off from a mooring, make sure the mooring is attached to the bow cleat closest to the wall. Switch cleats if necessary. Pull the sail all the way in and push the tiller towards the wall. The boat will power up and tack away from the wall. Once the boat is on the correct tack so that it is heading away from the wall, one person should release the boat from the mooring and walk back along the wall side of the boat. This action will help the boat turn on the correct tack to sail away from the wall. The more experienced person should do this job (the skipper if necessary); anyone can push the tiller towards the wall, while the person handling the mooring line can make or break the launch.
Do not drop the mooring line until the boat is powered up and sailing away from the wall. If necessary, more people can help hold the line and get it back on the cleat for another try.
When tacking in the Lynx, pull in the sail and start to turn the boat. The boat does not head upwind well, so do not pull in the sail too far. Make sure the centerboard is all the way down. Do not push the tiller all the way over, or the boat will slow down and may get stuck in irons. Instead, push it about three quarters of the way over so that the boat makes a gradual turn. (Of course, turning too slowly may also result in being stuck in irons.)
To gybe, get on a broad reach. Alert the crew to prepare to gybe, and pull the sail in about half way. Begin the turn; as the boat turns, the crew should continue pulling in the sail. Warn the crew as the sail comes around. Once the sail moves, let it back out and trim it properly for the new course. If the sail is pulled in too soon before the turn, or not let out quickly enough after the turn, the boat will develop strong weather helm and try to turn into the wind. Because the sail is so big, it is dangerous to do an uncontrolled gybe. Always pull in the sail and let it back out as the boat turns.
When heading downwind, never let the sail out past the stopper knots on the mainsheet. Never remove the stopper knots from the sheet.
The Lynx is more pleasant to sail if the centerboard is balanced with the sail. The boat can be steered with the centerboard: when it is all the way down, it will have weather helm and turn towards the wind. All the way up and it will have lee helm, and turn downwind. (This works best if all the weight is towards the back of the boat.) Adjust the centerboard so it has a slight weather helm for the current point of sail. This adjustment will reduce the pull on the tiller and reduce drag in the water caused by the centerboard.
Sometimes the centerboard gets stuck. Often it can be eased up and back down or dropped quickly to get it unstuck. Sometimes it helps to tack to take the pressure off the board.
If the wind is 12-15 knots, use the first reef. If it's 18 knots or higher, use the second. Reefing should be done on the dock rather than out in the river, although when out in the harbor it may be necessary to do it at sea. There are reefing clips at two locations at the end of the boom, and a reefing hook where the boom meets the mast. The sail has rings (reefing tacks and reefing clews) at the corresponding locations on the sail.
To reef the sail, lower both halyards. Have someone stand on the bow and lift up the lowest white ring as far up the mast as it will go. Someone else can hold up the end of the boom, to help the person putting in the reef. To put in the reef, first hook the clips into the reefing clew (at the end of the boom). The two clips go into the corresponding rings on each side of the sail. Make sure the strap connecting the two clips is not twisted, as every millimeter is necessary to put in the reef. Put in the first clip first and then stretch the sail and the clips until the second one is in. Once both clips are in, attach the reefing hook to the reefing tack where the boom and the mast meet. Make sure that corresponding reef points are used: do not try to use the second reef on the tack and the first reef on the clew.
When landing at the dock, have the crew put the fender in the water on the appropriate side. The fender will protect the boat when landing and indicate to the dock staff that the boat is coming in. Make sure the centerboard is fully down so the boat will turn sharply. Let the sail out to slow the boat down, and make a sharp turn about a boat-length away from the dock. Sharp turns slow the boat down. Have a crew member ready with the bow line to step out of the boat and tie up.
Putting Away the Boat
To put away the boat, get out the boom crutch and install it in the stern. Take out any reefs that have been put in. Lower both halyards; the red peak halyard will have to be lowered faster than the throat halyard. The white lazy jack lines will cradle the sail, causing it to fall along the boom. When the sail and boom are all the way down, rest the boom in the crutch. Then put the sail cover on the sail, starting from the end of the boom. Put the sail cover around the front of the mast but inside the two halyard lines. Tighten and coil the mainsheet and rest it on top of the tiller. Do not tie the mainsheet to itself - just coil it and drape it on the tiller. Put the tiller tamers on the tiller. Raise the centerboard.
The Lynx is self bailing, with two drainage holes near the centerboard. However if significant water gets in the boat, pumps are located in the dry storage area in the bow. This area also has an anchor and flares for emergencies. The boat has running lights; the switch is located in the stern next to the tiller.
Unexpected events happen while sailing. If the wind picks up suddenly and the boat is overpowered, head to wind, and let the sail out. Then sail back to the dock and reef. If it's really crazy, lower the peak halyard to reduce the sail area.
What if the forestay breaks? Head downwind to take pressure off the stay, and then lower the sail.
What about if the mainsheet gets lost? Try to retrieve it by reaching along the boom. If the boat is heading downwind, lower the centerboard all the way and turn the tiller all the way to one side to turn the boat into the wind. This action will bring the boom back over the boat. (Avoid this problem in the first place by never untieing the stopper knots in the mainsheet!)
What if the boat is stuck in irons close to the wall? Warn the crew to fend off. Have them get out the paddle and put out the fender. Land facing upwind. Try to cast off by pulling in the sail and pushing the boat onto the correct tack with the oar.
Outline for the Class
This is the outline used for teaching the Lynx class.
- Parts of the boat.
- Boat taxonomy.
- Tacking and jibing.
- Centerboard and balance.
- Panic moves.
- Rules of the road.
Things to remember:
- Never do an uncontrolled jibe.
- Never untie the stopper knot at the end of the mainsheet.
- Always use the fender when docking.
- Always use the chock on the dock line or the mooring line.
- Never cleat off the halyard lines so you can quickly drop the sail if necessary.
This section describes how to take one of MIT's Lynx 16 boats from the Sailing Pavilion to Boston Harbor. This document should serve as a guide only; nothing can take the place of experience of actually going on trips. The procedure is to put an engine on the boat, step the mast, motor through the lock into the harbor, raise the mast, and sail away. The process is reversed on the way back.
Sailing safely in the harbor involves many skills not covered here: reading a chart and understanding navigation aids, using a VHF radio, knowing how to use all safety equipment, understanding weather conditions and tides, anchoring, and right-of-way rules. Community Boating's harbor training class notes are a useful source for some of this information, but nothing substitutes for experience.
Before the Trip
Plan where you are going, and make sure that other people know the plan. Email Fran Charles and email@example.com to make sure the trip is okay. Tell them your float plan. Check the weather the night before and the morning of the trip; if there are thunderstorms, consider rescheduling.
We need an engine to get to the harbor, since we must step the mast to fit under the bridges between the Pavilion and the Harbor. It is also required to dock at Spectacle Island.
Installing the Motor on the Boat
The engines are not normally installed on the Lynx, so the first task is to put the engine on the boat, either the night before or the morning of the trip. First, tie up a Lynx in front of the bay with the motors, on the east end of the dock. The side of the boat with the motor mount should be closest to the dock. Tie a stern line as tightly as possible so that the motor mount is close to the dock.
Take a Tohatsu 4-stroke engine from the bay, and carry it vertically to the boat. You can gently rest the engine vertically on the metal "skeg" which sticks out below the propeller. Do not rest it on the propeller itself! Then tie a line to the mounting bracket on the engine, so that if you accidentally drop it, you can quickly pull it out of the water. Flip the engine and engine mount horizontally so that the bars on the mounting bracket will fit into the motor mount on the boat. Guide them into the mount and slowly rotate the engine down into the water.
Starting the Engine
After installing the engine, inspect it, and then start it to make sure that it works. First, check the fuel tank. If it hasn't been used in a while, and the fuel is old, then it's a good idea to put conditioner in it. You can get this from the dock staff. If you need to, add fuel. When testing the engine, it might be better to not add too much fuel, since if it's broken, it's easier to take the engine out with an empty fuel tank. The engine takes regular gasoline, the same as the launches. Take the cover off, and check that the engine has oil. If not, ask the dock staff to help you add oil.
When the engine is not being used (when sailing, or being stored overnight), it should be raised up out of the water. Before raising it, make sure the air is closed before to prevent gas from leaking out. Raise the motor by pushing a silver handle near the base and pulling up on the handle. Lower it using a black and metal lever. The engine should always be started with the propeller blades in the water.
To start the engine, make sure that the propeller blades are in the water. Open the air vent by turning the white cap on top of the fuel tank cap. Make sure the fuel line is set to use the internal tank using the lever on the right side of the engine. Check that the red safety button is being held open with the plastic wire. Pull out the choke. Set the throttle to the starting position. Make sure it is in neutral. Then pull the handle quickly to start it. Once it catches, immediately check that water is draining out of the engine; if water is not coming out, then stop the engine by pushing the red button. It uses water to cool itself and will overheat quickly of the cooling system is broken. Slowly push in the choke, and then turn down the throttle to idle. It may take a while to warm up before it will go into idle, especially if the engine has not been used in a while.
The engine takes gasoline. It helps to add fuel conditioner, but there is no need to mix it with oil, as with two stroke engines. One tank of gas can get from the Pavilion to the Harbor, to and from the docks at an island, and back to the Pavilion. However it's good to bring extra fuel in case of unexpected events. The Pavilion has containers for fuel; it is generally enough to take about one extra tank. If a tank already has gas in it, it's a good idea to add fuel conditioner to the gas in the tank. If the engine runs out of fuel while running, it can take a while to restart it. It is better to stop the engine, refuel, and then restart it rather than to let it run out of gas. The fuel container can be stored under one of the benches. It should be stored securely and tied down to avoid spilling.
Driving With the Motor
Next in order-of-operations for a harbor trip is stepping the mast. However I will cover driving with the motor here so that all the engine information is together.
When driving with the motor, the boat is classified as a power boat, and must give way to boats under sail and human-powered boats. To steer, use the boat's tiller rather than the one on the engine. The ease of pivoting the engine's tiller can be adjusted by turning a handle underneath the motor; set this to be fairly stiff so you don't accidentally move the engine's tiller. However it should be loose enough so that the engine tiller can still be moved to help turn more quickly if necessary and to make adjustments to the engine's direction.
To go forward, turn the throttle all the way down, and switch the lever on the left side of the engine from neutral to forward. To go faster, adjust the throttle upwards. To go into reverse, adjust the throttle down, then switch to neutral, and then switch to reverse; do not go directly from forward into reverse (or reverse into forward) as this damages the transmission.
When in tight spaces, lower the centerboard to give the boat more maneuverability. When traveling long distances, raise the centerboard to reduce drag. If the boat needs to turn faster, use the engine as well as the tiller.
You should be able to dock with the engine, and maneuver in fairly tight spaces in order to go through the locks and use the docks at Boston Harbor Islands.
Turning Off the Motor
Do not turn off the motor until the boat is controlled in another way, either with a line or with the sail. Set the throttle all the way down, and push the red button to turn it off. Raise the propeller out of the water if it will not be used in a while. Raise it overnight, and when under sail. It is okay to leave it in the water for a few hours when docking at an island.
Stepping the Mast
Make sure the sail is lowered, and put on the sail cover. First, get and install the mast crutch. They are stored in the workshop. There is a hole in the seat near the stern of the boat, and a matching hole in the floor. Put the mast crutch through the bench and into the hole on the floor.
Take off the forestay. Take a pair of pliers and a screwdriver. At the base of the forestay is the turnbuckle. Ask one person to lift up the boom, to take pressure off the mast. Ask a second person to push forward on the mast. Then take the ringding off the forestay pin and pull it out. Be careful not to drop it in the water. If you can't take it out, then you need to loosen the turnbuckle. There are two ringdings in the two screws in the turnbuckle. Take the ringdings out of the screws, but leave them attached to the turnbuckle itself. Then hold the flat part of the turnbuckle with a pair of pliers, and use a screwdriver to turn the lower part to loosen it. Be careful to turn it in the proper direction. Never entirely unscrew the screws from the turnbuckle; just loosen it. Try again to take out the forestay pin, and loosen the turnbuckle more if necessary. Once the pin is out, put the ringdings back in the screws on the turnbuckle. Otherwise the screws could fall out.
Once the forestay is off, get ready to lower the mast. Make sure all the lines are loose: peak halyard, throat halyard, and mainsheet. Pull the halyards all the way through the holes in the bow. Make sure the benches and runway are clear, as you will be walking from the bow towards the stern of the boat as you lower the mast.
Next, lower the mast. Stand on the bow with a helper. Lift the mast straight up four inches, using the handle on the front of the mast, and then bend it backwards, lowering it towards the stern of the boat. As the mast lowers, walk back towards the stern to gain a mechanical advantage as it comes down. Carefully lower the mast into the crutch.
Finally, clean things up. Take up the slack in the peak and throat halyards and coil the lines. Make sure there are no lines in the water, especially the forestay.
It's a good idea to use a checklist before leaving to ensure that nothing is forgotten.
Stuff to Take
Before leaving, make sure you have everything you need for the trip. It's often 20°F cooler on the water in the harbor than in Cambridge, so be sure to dress warmly!
Here is a partial checklist.
- nautical charts
- gas line and 3.2 gallon gas tank (filled).
- four stroke engine oil (1 quart)
- fuel conditioner (1 quart)
- soundmaking devices
- air horn
- life jacket (minimum one per person)
- food and water (suggestion: bring a cooler with ice)
- VHF radio
- Cell phone with the Pavilion's phone number
- pliers (2) (preferably needle nose pliers and channel locks for the turnbuckle.)
- philips head (2)
- flathead (1)
- cold and water resistant clothing
- extra line. (Sets of dock lines are stored in the harbor trip locker.)
- stern line (20 ft. gauge ??)
- spring lines (2) - 20 ft. gauge??,
- fender lines (2) - 3 ft each (gauge??)
- spare lines (short and long).
- spare parts for the Lynx
- forestay cotter pin (2)
- forestay cotter ring (4)
- forestay turnbuckle
- forestay turnbuckle cotter rings (or ring pins) x 3
- traveller shackle (1), cotter ring (3) and cotter pin (2)
- peak shackles (2), cotter pins, cotter rings and eyestrap bolts.
- pills for seasickness
- fenders (2) (in addition to the ball fender attached in the boat)
- flares (should already be in the front compartment.)
- anchor (should already be in the front compartment.)
- paddle (should already be under one of the benches.)
- first aid kit
- throwable life preserver
- battery for lights - make sure it is installed and tested - even for day trips - lights are good for a sudden storm.
- boat hook (currently in bay one)
Stuff to Do
- The night before.
- Confirm the boat has a reefing hook.
- Check that the yoke is in good shape.
- Pump bilge.
- Install engine.
- Unstep mast.
- Check battery. Confirm it's charged, even for day trips, in case of a storm.
- Tighten screws on the mast and the reefing clips.
- The morning of the trip
- Check the weather and tides.
- Send a float plan to firstname.lastname@example.org and email@example.com that includes
- Full list of attendees, including card numbers, and cell phone numbers.
- Weather forcast.
- Leaving and return times.
- Where we are going and what route we plan to take.
- Boat sail numbers.
- Remind everyone to use restrooms.
- Wash out the mast knuckle joint with fresh water. Once it dries, spray graphite on it. Otherwise the masts become very difficult to step.
Getting to the Harbor
Challenges on the drive to the harbor include recreational sail boats, duck boats, and tight maneuvering along the way. The map on the right shows the main obstacles: the old locks, the railroad bridge, and the operating locks.
First drive under the Longfellow Bridge. Stay towards the center of one of the channels underneath the bridge; avoid the pilings. Don't blindside boats on the other side of the bridge (especially duck boats). Make sure you can see oncoming boats before you drive under the bridge.
Next head towards the right side of the Science Museum towards the old lock and the Craigie Drawbridge. (Mark #1 on the map to the right.) The channel in the old lock is somewhat narrow. Don't blindside boats when entering the channel. Duckboats often come down the channel at the same time as your boat. Always pass port to port, and avoid the wall and other boats.
Once you pass the old lock, the next hazard is the MBTA railroad bridge. (Mark #2 on the map, and pictured open on the right. This bridge has very little clearance. Depending on the river level, the Lynx can often fit under the bridge with the mast stepped, but not always. The highest point on the Lynx after it is stepped is the base of the mast on the bow. Approach the bridge with the throttle at the lowest setting. Have the crew move towards the bow so it sits lower in the water. About 15 feet away from the bridge, set the engine to neutral, and go into reverse if necessary to very slowly approach the bridge. If the boat fits, the crew in the bow can draw the boat under the bridge hand over hand. If not, back off and give the signal for the bridge to be opened. The horn signal is one long blast and one short blast. However often the MBTA people do not pay attention to the horn, and you have to call them with a cell phone at the number posted.
Finally, drive underneath the Zakim Bridge towards the locks. Once about 100 feet away from the lock, sound two long and two short blasts on the horn or whistle, to signal that you want to enter the locks, or radio channel 16. Idle the motor and wait for the green light before moving forward. This part can be tricky as there is not a lot of space to maneuver and sometimes there are other boats waiting too.
Before going into the lock, make sure you have a bowline, a stern line, and fenders ready to go on one side of the boat. Once the light turns green, slowly drive into the lock towards the far end. Pull up about 3/4 of the way towards the far end of the lock, and put the engine in neutral. Have your crew wrap the bowline and stern line around the cleat. Do not tie off the cleat, since the boat will shortly exit the lock. Once the door opens on the other side, release the lines and drive out of the lock.
Raising the Mast
To raise the mast, first make sure all the halyards and mainsheet are loose, and the forestay is clear. Two people should walk along the benches towards the bow, slowly raising the mast. A third person makes sure that the lines are not tangled, especially with the engine. The third person also must raise the boom while the mast is lifted. Once the mast is vertical, it slides down about four inches into a slot.
Next, attach the forestay. First make sure the forestay is centered on the front of the mast, and swing it around if not. With one person holding up the boom, and a second person pushing forward on the mast, attach the forestay pin through the turnbuckle. If it is too tight, then loosen the turnbuckle. Once forestay is installed, put on the ringding and tighten the turnbuckle. Have someone lift up the boom, and tighten it with a screwdriver and wrench until the forestay is fairly tight (with the boom up). When the boom drops back down, it will be quite tight. Make sure to put the ringdings back in the turnbuckle once it is adjusted.
Finally, raise the sail and go sailing.
Stay in places with more than 5 feet of depth in the chart. Corollary: you should know where you are in the chart at all times. Abide by the rules of the road. Avoid the huge tankers and boats with limited maneuverability. When giving way, make a decisive course change so the other boat knows that you've seen them. The waves are larger in the harbor, so turn into the larger wakes. Know how to use the chart to navigate in the harbor and stay in the channel.
This website is a useful reference for navigating in the harbor: http://users.rcn.com/dhkaye/bosnav.html. It has pictures of the different types of buoys and advice on navigation and tides. Community Boating's harbor training class notes are also useful: http://www.community-boating.org/programs/adult-program/harbor-trips/harbor-trip-classes.
Docking at Spectacle Island
When docking at an island, head to wind, turn on the engine, and then lower the sail. Spectacle Island has a public dock. The fee is $20 if you stay over 20 minutes. You can call the dock with a cell phone or radio VHF 69. Give your boat name and size and ask for a dock. They will tell you which aisle to go down, and which side the lines need to be on. Make sure the lines and fenders are ready to go before motoring into the dock. On busy days, call farther in advance to ensure a spot.
When returning back to the Pavilion, lower the mast by the coast guard station in Boston Harbor. Return back through the locks, under the railroad bridge, through the old channel and back to the pavilion. Raise the mast, put the engine away, unload the boat, and return all equipment.
This document was created by Stefanie Tellex, based on extensive teaching by Keith Winstein and Wally Corwin. Additional information provided by Conan Hom.