Passage Planning Part 2: An Example

With Simon Midi Robitaille-Brisson and Luca Leboeuf.

This text is the second in a series of three on the construction of a passage plan. It makes use of electronics and is intended to be pedagogical, giving much more detail than normal.

In the first text, we discussed a four-phase approach to building a navigation plan:

1. An exploratory or “heuristic” phase;
2. A phase detailing boat and crew specifications;
3. A phase formalizing the routes;
4. A phase dealing with the peripheral dimensions of navigation.

This second text applies the approach to a boat delivery between the Bahamas and Québec (Canada). It focuses on the first two phases of the process. The third text focuses on the last two phases.

The navigation plan is real, in the sense that it was actually used to deliver a boat, but the boat’s name and specifications have been modified to preserve anonymity.

Boat Delivery Mandate

A customer has retained your services to transport his boat from Freeport, Bahamas to a marina near St-Jean-sur-Richelieu. He would like a departure around May 1st, to allow him to enjoy boating on Lake Champlain during the summer. The boat is a 35-foot Beneteau First named “HORUS”. The customer states that his boat is very slow, with a maximum speed of four knots. You are in charge of the delivery and must prepare the navigation plan.

Heuristic Phase

What are the possible routes? A first approach would be to take the Intracoastal Waterway from Miami up to Norfolk. A second approach would be to take the Gulfstream up to New York harbor. In either case, you could then take the Hudson River up to Lake Champlain, via the Champlain Canal and its locks, and on to St-Jean-Sur-Richelieu. A list of questions at this stage might look like:

1. Is the boat capable of an offshore route?
2. Is the general wind distribution compatible with the Gulfstream’s currents?
3. Where and how should customs declarations be made on arrival in New York?
4. They say you have to dismast when you take the Hudson River:
   • Where do you do it?
   • What are the bridges and underbridge clearances on the Hudson River?
   • What systems need to be disconnected to remove the mast?
   • Does the boat have a mast step on the bridge, or does it go all the way to the keel?
5. What is the Champlain Canal lock schedule?

These questions reflect what I had in mind when I started thinking about the navigation plan. They put a lot of emphasis on the Champlain Canal, which I knew less, than on the weather and the offshore segment, which I understood better. It is possible that the above questions are not relevant to you, because you know things I do not. What matters is to list the questions that you have not yet answered.

Offshore Passage

I started building the offshore segment because it is a more familiar terrain for me. It is also the beginning of the navigation. My first question was to see how much time at sea would be needed to get to New York, considering a boat moving at four knots.

I began the exploratory phase by looking at the pilot charts for the North Atlantic (image above). These charts are available free of charge on the US Army website. Pilot charts are useful because they show the statistical distribution of winds and currents. These statistical distributions take the form of a compass rose (image below) and show the general direction of the winds.

Compass Rose 101

The image below shows a compass rose. The surrounding text is taken directly from the french wikipedia page on pilot charts (amazingly, there is no equivalent in English). It translates to:

“Winds are represented by a blue compass rose in each ‘square’ zone, 5° wide in latitude and 5° longitude. It shows the distribution of winds that prevailed in the zone for the observation period. The arrows making up this rose are positioned every 45°. Their length indicates the percentage of the total number of observations in which the wind blew from their direction. The number of pennants at the end of the arrows indicates the average wind strength in Beaufort.

When the length of the arrow is too great for comfortable reading on the map, the percentage is indicated directly on the arrow. The number written in the middle of the wind rose indicates the percentage of calm periods.” (Wikipedia, n.d.).

The wind rose illustrated above shows a northerly wind 40% of the time (Force 7), followed by northeasterly winds (also Force 7). We also note that 3% of the time (the “3” in the center of the rose), there is no wind. In the region described by the wind rose, we can therefore expect a predominance of northerly and north-easterly winds. The Beaufort scale tells us that Force 7 winds correspond to winds between 28 and 33 knots.

Pilot Charts and Currents

The pilot charts also illustrate average currents on the map (green arrows). We can also deduce the predominant currents along the American east coast. Regular users will recognize the Gulfstream, affectionately known as “the magic carpet”, the surface current that carries warm waters northwards. A picture is worth a thousand words. Below, you can see the Gulfstream in mauve and white, via a screenshot of the currents model in the “Windy” electronic application.

What to Expect?

The pilot charts show that the distribution of trade winds is generally in the same direction as the Gulfstream. This is good news, as it will facilitate our progress. Knowing that we are leaving the Bahamas and that the winds come from the east, southeast and then south, I also made a mental note to myself that this would be sailing mainly on starboard tack, downwind (and giving us the advantage in terms of collision regulations). I also told myself that this statistical wind distribution would, in practice, be disrupted by lows and cold fronts from the US.

I also analyzed the offshore segment under another constraint: a crew member is taking his YachtMaster Ocean practical exam during the delivery trip. The exam requires a minimum of sixty nautical miles offshore for more than two hundred nautical miles for the segment to qualify for certification. I noted that as long as we stay in the Gulfstream, navigation gives us plenty of room to satisfy this constraint.

Finally, I looked at the launch schedule for Space X rockets at Cape Canaveral. It is of no practical value for passage planning, but if we can synchronize our passage with a shuttle launch, it gives us a front-row seat for a damned good show!

So I drew up an initial sketch of the navigation plan for the offshore segment, using the Gulfstream between the Bahamas and Cape Canaveral. This version was plotted in OpenCPN (screen shot below).

I then looked at the time required to complete this navigation by analyzing current strengths in the Gulfstream. I identified four parts with significantly different currents, which I combined with the boat’s speed to obtain an estimate of the duration of the offshore leg. The information is presented in the table below.

I then made a mental note to myself that I should check whether the boat is capable of supporting the crew for 7 to 10 days. Otherwise, this offshore leg would have to be rethought. I also made a mental note to myself that I should train the crew in depressions and cold fronts, at the very least, so that they would be able to recognize the warning signs. I then asked the crew’s first mate to prepare a mini-briefing on lows, fronts, ballot law and the associated weather cycles.

The weather dimensions also got me thinking about ports of refuge, should we need to return to land. So I made a list of towns more or less equidistant along the coast and also asked the first mate to prepare possible arrivals at each of these towns: identify a marina, some “google” screenshots helping with arrival and contact information. If all goes well, this information won’t be of any use, but it could help to orientate matters quickly should something go wrong. The work of the first mate (briefing and port of refuge entries) is available in the appendices of the french version of this text.

Finally, I wondered about the condition of the sails on the boat, and whether there was enough survival gear to make the offshore passage safely. At this stage, I have decided not to describe this route as “definitive”, preferring to wait for the answers to those concerns.

Hudson River Segment

I began my exploration of this segment by doing what anyone would do in this day and age: googling. Among other things, I found answers to the question of air draught on the New York State Canal, enabling me to identify when the mast should be removed. I also found references to marinas for dismasting in the Cruiser Forum.

I also found a good account of the techniques and time required to get through the locks on Arsenault‘s blog. Finally, I’ve read a lot about the process of declaring an arrival to U.S. Customs. Knowing how to “google” with questions in English or in French is invaluable, as it makes you benefit from accounted experiences in both languages.

I didn’t find everything on Google. I got hold of the section of the American “Waterway Guide” that deals with the Hudson River and the Champlain Canal, which I read in its entirety. It is invaluable for understanding tides and currents, as well as what to look out for when navigating. If I had been in Quebec when this plan was being drawn up, I would also have considered Luc Bernuy’s book on the Intracoastal Waterway.

I have deduced a great deal of information from these different sources. Here are the most important.

Firstly, the Champlain canal locks do not open before May 18, and are then only open continuously on weekends. As we leave on May 1st, this is a serious constraint on the passage plan. We have to be there on time… and there is no point in being early. At this point, I started thinking about the passage plan in terms of days before and days after May 18. The offshore part was counted in “days before May 18” and the part after the locks was counted in “days after May 18”.

Secondly, the Waterway Guide is rich in pilotage notes and information on the Hudson River. First, it is best to think of the segment between New York and Albany as coastal navigation. I also learned that the majority of the marine traffic – barges – communicate on VHF Channel 13. I also noted that tidal ranges are of 3 to 5 feet and currents are up to 1.5 knots. Already familiar with NOAA’s tide station sites, I figured this would be something to download on board once I arrived in New York.

On a more informative note, the guide states that in spring, there’s a lot of debris from melting snow, including tree trunks. So I made a mental note to myself that on this segment, we should probably only make progress during the day and with someone keeping watch at the front of the boat.

I finally noticed that several marinas had combs perpendicular to the current, which means we would have to dock with the current with the current moving towards or away from the combs, depending on the side.

I wasted a lot of time trying to figure out how to make customs declarations, only to realize that everything is done online, via the CBP ROAM application. It was at this point that I also wondered how to declare out of the Bahamas (which place/app?), that I figured I would need HORUS registration papers and that I would need a working cellular connection to declare online.

Finally, most sources indicate that the Catskills region is a good place to dismast. Two or three marinas have been identified as having the equipment to do so. I also made a mental note to myself that I would need equipment to dismast and build supports for the mast once it was horizontal.

All in all, this exploratory research made me realize the following constraints:

1. We have to be at the locks by May 18;
2. On the Hudson, in spring, it may be better to sail only during the day and with one person on standby at the bow;
3. The tidal currents are strong enough to take the tide schedule into account;
4. We should dismast in the Catskills area;
5. US customs declarations are done online. I need a wifi or cellular connection;
6. I still don’t know where to do the Bahamas customs/port declarations;
7. I need a plan for dismasting.

At this stage, the sequence of locks was still unclear. I had read Arsenault post too quickly, and the Waterway Guide presents the succession of locks in reverse order (starting from Montréal). Finally, I still could not see the sequence of towns along the Hudson River: is Catskills before or after Albany? How many days does it take to get to Catskills? Is it possible to get there by the 18th? I mention this to emphasize that it is typical of the heuristic phase: we do not have all the answers yet and things are blurry.

This confusion is partly due to the fact that OpenCPN does not offer the Hudson River charts. So I switched to Boating to plan this segment. To help me sort it all out, I took birdsview measurements of 40 nautical miles with the compass tool (image left), to quickly estimate the number of days required.

Everyone has their own preferences when it comes to navigation applications! I like OpenCPN for planning, but perhaps a lesson to be learned is that you can progress faster if you master more than one.

To help me visualize milestones, I also inserted markers at the Catskills and then at each lock (image right). This allowed me to see what the important stages looked like all along the river.

It allowed me to deduce that it would take about two days to cover the distance between New York and the Catskills. It also made me realize that Albany lies between the two.

It is still a long way from a complete passage plan, but the picture is clearer. One can see the milestones and visualize the route ahead in terms of steps.

At this stage, I left the exploration of the Hudson River aside, because it was clear enough. I started to concentrate on the boat’s capabilities.

A Few Pedagogical Remarks

Before moving on to the boat analysis, I would like to clarify a few dimensions. Firstly, if this is the first time you read about compass roses, or hear about trade winds and the Gulfstream, this a lot of advanced information to digest. The purpose of this text is not to train you in marine meteorology, nor to teach you how to read nautical charts. Rather, this text shows you how to integrate this knowledge into a navigation plan. If you are less familiar with the basics of charts or weather, it is a good idea to take a course to better understand them.

Secondly, this initial exploration neglects tactical considerations related to the starting window and adjustments during the offshore leg. The final version of the plan includes an uncertainty of plus or minus three days on the departure date to maximize the chances of having a good weather window during the offshore leg. It is important to remember that a sailing plan is not a rigid object, but a general idea of options, including preferred options, but also other options (ports of refuge, etc.).

Thirdly, there is still one important dimension missing from the offshore segment: arrival in New York harbor. I’ve deferred it to the section on chart plotting.

Fourthly, I have mapped out the offshore segment even though we are technically in the exploratory phase. This is partly because it is a “terrain” I am more familiar with. That said, in the coastal segment, I was much slower to get to plotting a route because I was less familiar with the specifics of the Hudson River. I had to read and learn.

Fifthly, I presented all the sources on the Hudson River in two or three nice paragraphs summarizing the results. In practice, it took me a long time to find these sources, about two days of “wasted” research, not counting the associated reading. The text above perhaps has this flaw, namely that it presents the results a little “pre-digested”. In practice, you have to search, sort the sources, retain those you consider relevant, make mistakes, find other sources, and so on. The exploratory phase takes time!

The important thing to remember here is that your elaboration speed and approach may differ from mine, because your knowledge differs from mine. The important thing is to use the heuristic phase to figure out the gray areas that needs to be understood and to strengthen your weak spots.

Boat and Crew

To preserve the customer’s anonymity, the boat data below are taken (in part) from the “sailboatdata.com” website. They may differ from other specifications specific to the Benetau First 35. For obvious reasons, the crew CVs are not detailed either.

The “First 35” has a draught of just under two meters and an air draft of just under 15 meters (14 meters mast + freeboard estimated at 1 m), i.e. 49 feet. This is an important constraint, as 49 feet is greater than the 45 feet of air draft guaranteed on most bridges on the Intracoastal Waterway.

This doesn’t mean that it’s impossible to pass under these bridges (you can play on low tides, or tilt the boat, etc.), but it does mean that it would significantly slow progress if you were to take the Intracoastal from Miami. You’d have to wait for the tides, play with weights to heel the boat, or dismast.

The boat has 201-liter water tanks, and the customer reports having an additional 100 liters “strapped to the deck”. The fuel tank is 65 liters, with an additional 40 liters on deck. The customer also tells me he has a stormjib, a second mainsail and general boat maintenance equipment. He says he does not know how many hours are on the engine, a Yanmar 30hp, but assures me he had the oil changed in early April, before he returned to Quebec.

The boat has a dinghy with a 2-stroke engine (2.5% mixture), which is currently deflated and tightened into the sailboat. The customer tells me that the life jackets are not on board, that there is no electronic navigation equipment, and that the autopilot control belts need replacing. There is no watermaker on board, but there is a portable generator.

On the electrical front, the customer reports having over 300 Ah of lithium batteries, new batteries, plus 400 Watts of solar panel. He also tells me that the batteries are connected to the alternator via an MPPT charge controller, and that some systems are 24 volts rather than 12 volts. He also tells me that he has replaced the basic alternator with a more efficient model.

Water Capacity

The longest sailing segment is the offshore segment, lasting up to ten days. With a generous consumption of six liters per person per day, for four people, the crew needs 240 liters. This requirement is within the on-board capacity. At this point, I’m also reminded that diversifying water storage sources is a good strategy. If one source turns out to be contaminated, the others remain potable. (Did I ever tell you the story of a customer who mistook a diesel cap for a drinking water cap?) I make a mental note to buy bottles of drinking water.

Engine Nominal Range

You can learn a lot from reading an engine’s technical specifications. The most important figure, for planning purposes, is the one detailing the relationship between consumption and motor speed. For a rotation speed varying between 2000 and 2600 RPM, the consumption of a Yanmar 30hp is between 2 l/h and 4 l/h (image below). I assume (a big “guesstimate”) that the boat will go between 5 and 7 knots at these speeds, which gives the nominal ranges in the table below.

This is a typical result of several marine engines. The range decreases with an increasing speed. This happens because fuel consumption increases more than proportionally to the speed: you can go faster, but all things considered, you consume more diesel. In doing so, you can go less far.

I would also like to point out that we have got much more than 100 nautical miles range to get back to port, in the event of major damage during the offshore leg. For the inshore segment on the Hudson River, I figure we will be able to find marinas where we can refuel. Otherwise, I note that we won’t be overworking an engine with an unknown number of hours on purpose.

Electric Systems

The information provided by the customer is sufficient for me not to worry about electricity at the planning stage. 400 watts of solar, at 80% efficiency for 6 hours, provides 1920 Wh (“watt-hour”), or 160 Ah (“amp-hour”). It is not an infinite budget, and a large part of it will certainly be consumed by the autopilot and the fridge, but it is not world hunger either. At worst, we will start the engine for an hour or two during the offshore segment, to recharge the batteries.

Onboard Material

I note that we will need to inflate the dinghy, and bring life jackets and lifelines. I also note that we will need to take some navigation equipment on board. I also think it might be a good idea to bring some gasoline to run the generator. I do not plan to use it, but it is an energy option I prefer to have “just in case”. I am also in touch with the customer to discuss purchases for various items. We consider how the equipment can be delivered to Freeport. After some discussion, bringing equipment directly in the suitcases seems to be the simplest approach.

Conclusion

At this stage, we have enough information about the boat, its capabilities and the various constraints involved in route planning. I am reasonably confident that we can do the offshore leg. I am also convinced that we can get to the locks by May 18. The navigation plan is starting to take shape!

All that remains is to complete the missing navigation elements: arrival in New York, coastal routes, and the tide schedule. I still have not thought about how to dismast the boat, nor about clearance procedures for the Bahamas. I still do not know where to buy groceries, or which marinas we will be sleeping in along the way. I also need to make a few checklists to make sure I do not miss anything.

These considerations will be the subject of the third text, in conjunction with the map outlines.

References

Arsenault, J. F. (2022). Jour 14 : Écluses 1 à 6 du Canal Champlain, document retrieved online in April 2024 from this address.

Bernuy, L. (2018). L’Intracostal, le guide 4e éd., Éditions objectif sud, ISBN 9782981230218.

Hunter Parrot (2011). Boat Balls 2, video retrieved online in April 2024 from this address.

CruisersForums.com (s.d.). Mast and de-demast on Champlain canal / Hudson river, document retrieved online in April 2024 from this address.

Gouvernement du Canada (2022). Circuits et intinéraires – Lieu historique national du Canal de Chambly, document retrieved online in April 2024 from this address.

_______________________ (2017). Tableau de l’échelle Beaufort, document retrieved online in April 2024 from this address.

Kennedy Space Center (s.d.). Launches and Events, document retrieved online in April 2024 from this address.

Maritime Safety Information (s.d.). Atlas of Pilot Charts, document retrieved online in April 2024 from this address.

National Oceanic and Atmospheric Admninistration (s.d.). What is the Gulfstream?, document retrieved online in April 2024 from this address.

__________________________________________ (s.d.). Tides and currents, document retrieved online in April 2024 from this address.

Navionics.com (s.d.). Navionics Boating App, document retrieved online in April 2024 from this address.

New York State Canal Corporation (s.d.). Bridge Heights, document retrieved online in April 2024 from this address.

Noonsite.com (s.d.). USA Pre-arrival procedure for Yachts, document retrieved online in April 2024 from this address.

OpenCPN.com (s.d.). OpenCPN, document retrieved online in April 2024 from this address.

Pier du Sud (2024). Faire un plan de navigation: 1ère partie, document retrieved online in April 2024 from this address.

__________ (2023-a). Faire le bilan énergétique de son voilier, document retrieved online in April 2024 from this address.

__________ (2023-b). Qu’est-ce qu’un contrôlleur de charge MPPT?, document retrieved online in April 2024 from this address.

Royal Yachting Association (s.d.). RYA Yachtmaster Ocean Exam, document retrieved online in April 2024 from this address.

Sailboatdata.com (s.d.). First 35 (Beneteau), document retrieved online in April 2024 from this address.

U.S. Customs and Border Protection (2023). CBP Reporting Offsite Arrival – Mobile (ROAM), document retrieved online in April 2024 from this address.

______________________________ (2024). Pleasure Boats, document retrieved online in April 2024 from this address.

Villeneuve, B. (2022). Météo Marine, LSM Latitude, ISBN 9782981436917.

VoileMercator.com (s.d.). Cours théoriques, document retrieved online in April 2024 from this address.

Yanmar.com (s.d.). 3YM30AE, document retrieved online in April 2024 from this address.

Waterway Guide (s.d.). Waterway Guide, document retrieved online in April 2024 from this address.

Wikipedia (s.d.). Horus, document retrieved online in April 2024 from this address.

________ (s.d.). Canal Champlain, document retrieved online in April 2024 from this address.

________ (s.d.). Pilot charts, document retrieved online in April 2024 from this address.

________ (s.d.). Loi de Buys-Ballot, document retrieved online in April 2024 from this address.

Windy.com (s.d.). Windy, document retrieved online in April 2024 from this address.

Appendices

The appendices can be found in the original text (in french).