Before you set sail for your next destination, it’s recommended you create a plan for your passage. As with any trip, a bit of forethought and preparation can help get you safely (and with a happy crew!) from A to B and to avoid nasty surprises.
If you’re completely new to the topic have a watch of this short video, where the team from Boat Notes talk us through their thinking. It’ll help put what’s below in a bit more context :)Here are the main things you’ll need to consider when planning a passage:
- Pick a destination (often the most difficult bit!).
- Check how far it is away.
- Check the weather forecast to see if it is suitable for your passage, boat and crew.
- If you’re in tidal waters, check for tidal constraints and use them to help determine your ideal departure time.
- Plan to make best use of any tidal streams.
- Check for hazards on route, plan to avoid them.
- Consider ports of refuge in case the weather changes.
- Plan your port entry and exit (pilotage plan).
- List bearings and distance to waypoints to ensure you don’t make a mistake when entering them into your GPS.
This is one of the most important questions you need to answer. How long would you like to spend sailing? You’ll need to know the average cruising speed of your boat; most sail between 5-6 knots per hour but if it’s a smaller boat, the cruising speed may be less. If you’re sailing with an experienced crew used to longer passages then a 6-8 hour sail will likely be suitable. If you’re sailing with an inexperienced or young crew you may only want to consider a 3-4 hours on the water.If you have a destination in mind then you’ll need to know how far it is from your starting point (in nautical miles) then you can calculate how long the trip will likely take.
What is the weather forecast and is it suitable for the boat and crew to manage during the passage? What’s the forecast for the return trip (if applicable)? The direction of the wind is very important; if you have to sail into the wind then you may want to add a third of the total distance to allow for the extra distance you’ll need to sail – bear in mind it may also be a more uncomfortable passage! Consider reefing in harbour before you leave and ensuring you have plenty of snacks and drinks to hand. If the wind is directly behind the boat, then it’ll be a more comfortable sail, but boat speed will be reduced if the winds are light. Could the crew handle flying a downwind sail like a spinnaker or cruising chute? What if the weather changes? Do you have enough fuel to motor if the wind dies and have you considered alternative closer ports as a safe haven if you encounter a problem? Is your safe haven accessible at all states of tide?
If you sail in a non-tidal area then you need not worry about tides, but if you do then you’ll need to take the tidal streams and heights into consideration. Are there any tidal restriction leaving your home berth? If so you’ll need to work out when you can leave. This will give you a departure time. You’ll also need to know tidal heights. Are there any tidal restrictions at the destination? If so then you’ll need to work out when you can arrive. This will give you an arrival time which in turn will allow you to work backwards to figure out a departure time. You’ll also need the tidal heights for the destination. A tide going with you will increase your cruising speed; a tide against will decrease it. Consider the wind direction in relation to the tide; wind with tide will give a smoother passage than wind against tide (which could be pretty grim).
You may have a departure time based on a tidal height restriction, but often you will want to plan your departure to take advantage of the tidal streams. Work out when the tides are in your favour, consider how long it will take to leave you berth. When the tide is turning the flow is generally at its weakest so consider leaving before the tide turns if you are making a longer passage. Sailing against a weak tide for the first hour will allow you to take advantage of the full tide. Or sail in the shallows where there is often a back eddy before the tide turns.
You’ll need to prepare a pilotage plan (navigation that takes place in sight of land) for your departure and destination, if there’s a possibility of a night departure or entry ensure you include lights. Look at the pilotage for any alternative ports you have considered – if you’re experiencing a problem the last thing you’ll want to do is work out how to enter the port! It;s useful to know the height of tide for your alternative port as this will give you a minimum depth of water that you can sail in.While planning your passage note any hazards en route, take care of tidal races and plan your passage to avoid them. Watch out too for common errors. A classic mistake is to plan a longer passage than necessary. Mark up your waypoints and remember that a waypoint doesn’t have to be on a buoy. Make sure you know the distance and bearing between your waypoints as this will allow you to double check that you have entered them into the GPS correctly. Knowing the tidal height during the passage will make decisions easier, consider listing the depth of tide hour by hour, this way you will know how close to shore you can sail at all times.
Thanks to Simon at Equinox Sailing for contributing this article.