Boat Handling

How to predict wind direction and strength by reading a weather chart

By on Jul 16, 2015 in Boat Handling, Navigation, Practical, Preparation | 0 comments

Weather charts, also known as surface pressure or synoptic charts, contain a lot of information that helps weather forecasters make predictions about the weather and sea conditions. Before going to sea it is always a good idea to study weather charts and work out how the weather is likely to evolve in the area you plan to sail in. This sequence of four synoptic charts predicts the weather over a 36 hour period. Isobars on a weather chart The circular lines are isobars, similar to contour lines on a land map, and join areas of equal barometric pressure.  Air moves from high to low pressure and when the difference in the pressure is greater, the airflow or wind will also be greater.  Isobars that are close together indicate stronger winds. Isobars that are further apart indicate lighter winds. The wind scale inset in the top left of the chart helps you to forecast wind speed. Wind direction In terms of the wind direction, in the northern hemisphere air moves around high pressure in a clockwise direction and low pressure in an anticlockwise direction, so isobars on a weather map indicate the direction and speed of the wind as well as the pressure. Fronts The lines with triangles and semi-circles represent fronts. Warm fronts on a weather map are shown with semi-circles and cold fronts with triangles. The way in which the semi-circles and triangles point shows the direction in which the front is moving. Occluded fronts and troughs Where a cold front and warm front meet an occluded front is created, shown by lines with overlapping semi-circles and triangles.  Black lines with no semi-circles or triangles are troughs and show areas where the air is unstable and showers tend to form. It is a good idea to print out the latest weather charts for your area before you set sail and refer to them on your...

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Weather forecasting tips

By on Jul 16, 2015 in Boat Handling, Navigation, Practical, Preparation | 0 comments

Most weather forecasts present a general picture of what to expect in your area over a given period of time. We rely on such forecasts to provide basic information, but the actual weather and sea conditions we experience don’t always tally with the general view. It is not necessarily the forecasters’ fault if the conditions we experience don’t tally with the forecast, as it is the local tides, topography and sea breezes that interact with the basic picture and give rise to the actual conditions we experience out on the water. Before deciding whether it is safe for your vessel and crew to go afloat, it is a good idea to study all available forecasts.  A major part of making that decision is done through observation and being able to assess where in the forecast weather pattern you actually lie.  Has that predicted front passed through yet, what are the clouds telling you, what is the wind strength, how has it changed through the last few hours and what is the barometer doing?  Study your charts and estimate when and where you can expect wind against tide.  Are the elements going to clash severely and if so when is this going to happen?  Will you need to avoid being in that area or will the conditions be manageable? Below are some weather forecasting tips to help you reach your decision. Sources of weather forecasts It is a good idea to gather as much reliable information as you can.  Sources of weather forecasts include: National meteorological offices. Internet – good source for GRIB forecasts (Gridded Information in Binary files),eg UGrib, weather charts, web services eg Windguru also back-up to VHF, NAVTEX, INMARSAT-C and SSB radio. MSI (Marine Safety Information) broadcasts on VHF and SSB radio. Public service broadcasts on radio and tv. NAVTEX, Weatherfax and INMARSAT-C. Harbour and marina offices. Local knowledge -talking to locals in the know, for example fishermen, can help you decide. With information gathered, compare a number of pressure charts to see how the weather patterns have been forecast to evolve in your area over a number of days. This will help you to judge when fronts will pass through, what local conditions will be as a...

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Anchoring – getting it right is not always straightforward

By on Jun 10, 2015 in Boat Handling, Practical, Preparation | 1 comment

If you can set an anchor correctly with confidence and know your boat will be safe in a secure anchorage, then you can rest in comfort and will not need to rely on moorings and marinas when cruising. Anchoring is one of the most important boat handling skills. If you do not know how to anchor correctly then you risk endangering your boat and also others who might be anchored nearby.  And if your anchor is unsuitable for the type of seabed beneath your keel then there is a high chance of the anchor dragging.  For some boat owners, the fear of the anchor dragging means they stay awake all night, as a result getting little or no sleep and most likely stressing out their crew into the bargain. Getting anchoring right is not always straightforward.  It can be confusing with the many types of anchor available and there will always be conflicting opinions on which anchors would be best suited for your boat and your chosen cruising ground.  Anchors and chain weigh considerable amounts, so loading up with excessive amounts of chain and anchors can affect a vessel’s performance and only really be necessary if planning a long distance voyage along a variety of potentially exposed stretches of coastline. Types of anchor  Choosing the type and size of anchors and cable to carry aboard will depend on the type and size of your vessel and the sea area it is being used in.  Most importantly, choose anchors that are big enough for your vessel and those which are recommended by the manufacturers.  Cruising yachts normally carry at least two types of anchor, plus suitable lengths of chain and rope cables.  Types of anchor include: Bruce – good power to weight, easy to handle, holds well in mud, sand and rock CQR or plough – good power to weight, stows well on bow roller, though awkward on deck. Holds well in mud and sand.  Very popular and reliable Delta – good power to weight, also plough shaped. Stows well on bow roller Danforth – stows flat, good kedge anchor, hard to break out of mud. Excellent back up anchor. Prone to pull out if the wind or current reverses...

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Getting a tow for your sail or power boat at sea or on inland waterways

By on Jun 7, 2015 in Boat Handling, Emergencies, Practical | 0 comments

FREE tips from the Safe Skipper App for iPhone/iPad/Android: Getting a tow for your sail or power boat Plan how to secure a tow rope to your boat. The tow rope must be attached to strong deck fittings As a rescue boat approaches, warn them of any debris or loose lines in the water If you are being rescued by a lifeboat, follow their instructions – they are experienced in rescue techniques If necessary back the tow rope with other ropes to lead to other cleats and strong points on deck Avoid using knots or loops that cannot be released under load Protect the rope from chafing using plastic tube, rags or fenders When being towed in a small boat, you will need to keep the weight well aft to keep the bow up If the boat is down by the bows you may need to be towed from astern The towed boat should always steer to follow the towing boat unless the steering has been disabled The use of a drogue to aid towing can be...

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Always have an emergency grab bag to hand when at sea…

By on Apr 24, 2015 in Boat Handling, Emergencies, Preparation | 0 comments

  Grab bag: In the event of having to abandon ship, it is recommended to have a designated waterproof bag to carry essential emergency items.  These might include items already in use on the boat, as well as some already stored in the bag. Emergency at sea – bag contents: • Handheld GPS  • Handheld VHF  • PLB/EPIRB  • Flares  • Sea sickness pills  • Torch and batteries  • First aid kit  • Thermal protective aids  • Medication  • Food and water  • Ship’s documents  • Personal documents  (see Safe Skipper for more – the app for all boating...

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Man Overboard Drill

By on Apr 16, 2015 in Boat Handling, Emergencies, Preparation | 0 comments

How to respond to crew overboard under sail • Keep the MOB in sight • Tack into the heave-to position, do not adjust the headsail sheets • If under spinnaker, alter course to windward and haul sail down immediately • Throw buoyancy to the MOB • Mark MOB with dan buoy • If within earshot of MOB reassure them you are manoeuvring into recovery position• Steer onto a beam/broad reach and sail away• Sail for about 5 or 6 boat lengths• Tack, aiming the leeward side of the yacht at the MOB • Let out the headsail and mainsail sheets until the main flaps • Keep the angle of approach as a close reach, so the sails can be powered and de-powered under full control • Use one sail only in breezy conditions • Approach the MOB slowly. Don’t be tempted to approach too quickly • Pick up the MOB to leeward, aft of the mast • In light conditions, approach MOB to windward and drift down towards casualty so they can be recovered on leeward side (taken from the Safe Skipper app for iPhone, iPad &...

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