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ColRegs Rule 14 – Head-on Situation

By on Sep 12, 2015 in Boat Handling, Navigation, Preparation | 1 comment

ColRegs Rule 14: Head-on Situation (a) When two power-driven vessels are meeting on reciprocal or nearly reciprocal courses so as to involve risk of collision each shall alter her course to starboard so that each shall pass on the port side of the other. (b) Such a situation shall be deemed to exist when a vessel sees the other ahead or nearly ahead and by night she would see the mast head lights of the other in a line or nearly in a line and or both sidelights and by day she observes the corresponding aspect of the other vessel. (c) When a vessel is in any doubt as to whether such a situation exists she shall assume that it does exist and act accordingly. (From Nautical Rules of the Road – ColRegs for power boating and sailing – a Safe-Skipper...

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Know your Navlights & Shapes – essential for all skippers

By on Jul 17, 2015 in Communications, Navigation, Preparation | 0 comments

Know your Navlights & Shapes International Regulations for Preventing Collisions at Sea (ColRegs) Anyone who is responsible for a vessel at sea, from the smallest dinghy to an ocean going supertanker, day or night, must be able to recognise other vessels and quickly interpret what they see around them. This is not always easy, especially in crowded coastal waters. Rule 21(b) – “Sidelights” means a green light on the starboard side and a red light on the port side each showing an unbroken light over an arc of the horizon of 112.5 degrees and so fixed as to show the light from the right ahead to 22.5 degrees abaft the beam on its respective side. In a vessel of less than 20 metres in length the sidelights may be combined in one lantern carried on the fore and aft centreline of the vessel. Rule 23 – Power-driven vessels underway (a) A power-driven vessel underway shall exhibit: (i) a masthead light forward; (ii) a second masthead light abaft of and higher than the forward one; except that a vessel of less than 50 metres in length shall not be obliged to exhibit such light but may do so; (iii) sidelights; (iv) a sternlight. (b) An air-cushion vessel when operating in the non-displacement mode shall, in addition to the lights prescribed in paragraph (a) of this Rule, exhibit an all-round flashing yellow light. (c) A WIG craft only when taking off, landing and in flight near the surface shall, in addition to the lights prescribed in paragraph (a) of this Rule, exhibit a high intensity all-round flashing red light. (d) (i)A power-driven vessel of less than 12 metres in length may in lieu of the lights prescribed in paragraph (a) of this Rule exhibit an all-round white light and sidelights; (ii) a power-driven vessel of less than 7 metres in length whose maximum speed does not exceed 7 knots may in lieu of the lights prescribed in paragraph (a) of this Rule exhibit an all-round white light and shall, if practicable, also exhibit sidelights; (iii) the masthead light or all-round white light on a power-driven vessel of less than 12 metres in length may be displaced from the fore and aft centre...

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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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Boating Rules of the Road – International ColRegs

By on Apr 17, 2015 in Navigation, Preparation | 0 comments

    International ColRegs Rule 7: Risk of Collision Anyone who is responsible for a vessel at sea, from the smallest dinghy to an ocean going supertanker, must be able to recognise other vessels around them day or night, whatever the visibility. They need to be able to quickly interpret what other vessels are doing, who has right of way and what action they should take to prevent a possible collision. This is not always easy, especially in crowded coastal waters and harbor. Rule 7: Risk of Collision. (a) Every vessel shall use all available means appropriate to the prevailing circumstances and conditions to determine if risk of collision exists. If there is any doubt such risk shall be deemed to exist. (b) Proper use shall be made of radar equipment if fitted and operational, including long-range scanning to obtain early warning of risk of collision and radar plotting or equivalent systematic observation of detected objects. (c) Assumptions shall not be made on the basis of scanty information, especially scanty radar information. (d) In determining if risk of collision exists the following considerations shall be among those taken into account: (i) such risk shall be deemed to exist if the compass bearing of an approaching vessel does not appreciably change; (ii) such risk may sometimes exist even when an appreciable bearing change is evident, particularly when approaching a very large vessel or a tow or when approaching a vessel at close range. Check out Boating Rules of the Road app for iPhone & Android for a great easy way to keep the rules handy when you’re out on the...

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ColRegs when sailing single handed

By on Mar 22, 2015 in Navigation, Preparation | 0 comments

  Don’t neglect the Colregs when sailing single handed Sailing single-handed represents several challenges for skippers, not least how to manage sleep, keep watch at all times, and avoid breaching IRPCS Colregs Rule 5. If you can’t keep a look out whilst sleeping, you’re technically in breach of Rule 5 of the ColRegs which states that ‘Every vessel shall at all times maintain a proper look-out by sight as well as by hearing as well as by all available means appropriate in the prevailing circumstances and conditions so as to make a full appraisal of the situation and of the risk of collision.’ Colregs Rule 5 is the critical rule The RYA says: ‘This is the most important Rule. If it is not observed, the rest of the Rules might as well not exist’. The danger of breaching Rule 5 of the Colregs is why the RYA has a policy of not endorsing single-handed races. However, in reality the single handed skipper must sleep a bit and typically manage sleep according to surroundings. Tips for sailing singlehanded on long distances include: Setting a course further offshore, where there are fewer boats, fewer nets, lobster pots and bits of drift wood. Sizing up the density of the traffic around you. In the middle of the ocean, you can allow yourself to rest with a lower level of risk, especially if you have (see below) a working radar with an alarm. Keeping your eyes open at all times when you’re crossing a shipping lane, or a fishing area. Fitting electronic aids but not relying on them too heavily: Radar target alarms and active radar target enhancers (such as Activ’Echo or Sea-Me) will help make your yacht appear larger on another vessel’s radar display. Fitting an AIS unit (now a requirement in the Vendee Globe Sailing Instructions) and ensuring it is switched on (which is specified in the Barcelona World Race SIs). The safest course of action is not to rely too heavily on electronic aids; they must not become crutches and must not supplant the skipper’s instincts. For those training to be single handed sailors a good tip is to practise going below during short afternoon excursions, and to spend 5 minutes performing specific tasks like checking charts, making coffee and practising...

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