Category Archives: Navigation

A Foggy Trip to Newport

In less than a month, our first race of the season will begin. The Annapolis Newport Race is one of the iconic races on the East Coast of the U.S. and we are delighted to have Suntex Marinas as one of our key sponsors this year. They have helped bring a sense of adventure and excitement to our racing season.

routeWith the Annapolis Newport Race coming up, and the Volvo Ocean Race boats at Newport, RI, I thought it would be a great opportunity to take the available crew up to Newport on the ocean side for some pre-race training. It would be the first sail of the season for them. Given that the plan was to leave on Mother’s Day, we decided to leave later in the evening around 9 pm. After all, Moms were the priority that day!

Manhattan at DuskThe weather forecast was generally good. Winds were forecasted at 10-15 knots (with gusts to 20 knts) from the south and shifting to the southwest later. That would make for a great broad reach through part of the night, then a fun spinnaker run up to Newport. The less exciting part of the forecast was the dense fog advisory in effect until the following day around noon.

Fortunately, the fog held off as we left Liberty Landing Marina and headed under the Verrazano Bridge out onto the open ocean. It was a beautiful initial three hours of sailing on a warm evening with stars acting as our guide. Alas, it was too short though. By 12:30 the fog began to roll in and ended up staying with us for the remainder of the sail up to Newport.

Some of the crew were initially nervous about sailing in dense fog. After all, how can you sail if you can’t see? Granted, at first it can be quite intimidating, but if properly prepared, it is manageable. Obviously, the biggest concern on the ocean is the potential of a collision with a (usually much bigger) boat. However, there are steps that can be taken to minimize the risk. Namely, understanding how to use radar and knowing how to use AIS (Automatic Identification System).

digital_radar_imageOne of the most important tools for sailing at times of limited visibility is radar. Radar gives us the ability to “see” objects such as land, other ships and navigation markers even when there is dense fog and in the dark of night.  However, it does take time to understand radar and to properly interpret what appears on the screen. The crew will have good practice on this sail.

Another tool is AIS which will show nearby boats as triangles on a chart plotter (electronic map). Clicking on the triangle will give you that boat’s navigational details including whether it is on a collision course. The two key terms to know with AIS are CPA (closest point of approach) and TCPA (time of closest point of approach). This data essentially tells you how close the risk of a collision is and when that could occur.

Once the crew settled in to a night of sailing in fog off the coast of Long Island, people relaxed somewhat. However, they soon encountered another challenge. Helming a true course in fog can be quite difficult as there are no visual cues such as the moon or stars to help steer a straight line. Nevertheless, there are still sensory clues that can help. One of the techniques I teach is to feel the direction of wind on your face or head when you are sailing on course and try to constantly be sensitive to that, using it as a guide. Also, the boat will have a certain motion as it sails with the waves on a particular direction. Learning to feel that is important for good helming. Finally, there is the compass that can be used to help steer a straight course. Just remember that you don’t want to simply react to compass changes as the slow swinging of the compass can lead to over steering.

Sailing on a broad reach along the coast there was a time or two when the person at the helm accidentally gybed and began sailing in the opposite direction (oops!). But with time, everyone improved remarkably. For those whom it was a first time sailing in fog at night it was a great learning experience, and they improved considerably by the end of the trip.

foggy sailDaylight hours did not bring any relief from the fog. It stayed socked in around us with visibility less than ½ mile and at times, less than a hundred yards. It was disappointing for some to pass close to Montauk Point without being able to see it. Later as we rounded Block Island, we passed navigational markers less than a quarter mile away although we could not visually see them. However, they did show up on radar and they could be heard through the dense fog.

castle hill lightIt wasn’t until we were close to Newport that we saw our first sight of land. Castle Hill Light slowly appeared out of the fog as we made our approach, and then one by one other landmarks began to appear out of the mist.  As we rounded Fort Adams, we could see the Volvo Ocean Race Village and the six boats all tied up at the docks. It was a beautiful and exciting sight!

 

castle hill

 

Transiting Hell Gate

maelstromHell Gate, just the sound of it brought many a man to their knees in fear. Just a small stretch of the East River between New York Harbor and Long Island Sound, for centuries it conjured up images of a treacherous journey through whirlpools large enough to swallow ships and with wild rapids churning up giant standing waves and hidden rocks ready to rip the bottoms out of ships.

Originally named by the Dutch when New York was Nieuw-Amsterdam, Hell Gate or Hellegat was first navigated in 1614 by the Dutch explorer Adriaen Block. Since that time hundreds of ships have sunk in the narrow channel. Some historians believe that “one in 50 ships trying to run the gauntlet of Hell Gate was either damaged or sunk” with up to 1,000 ships running aground annually in Hell Gate prior to the 1850’s. One of the most famous to have ended up at the bottom of Hell Gate was the British Revolutionary War frigate H.M.S. Hussar in 1780. Laden with millions of dollars (at the time) in gold and silver and over 150 men, she struck a rock and quickly sank.

During the late 19th century the U.S. Army Corps of Engineers began to blow up the rocks and reefs which plagued the treacherous tidal straight. At one point, the Corps used so much explosives that the blast was felt as far away as Princeton, NJ.

east-river-wavesToday, the short stretch of river is much more benign than days of yore, but it can still be a challenge to navigate for the unprepared. Currents can run up to six knots at times and tugs with barges under tow can suddenly appear around the sharp bends of the channel. Adding to that, is the possibility of steep five foot waves near the 59th Street Bridge due to upwelling caused by the subway tunnels running under the river.

Timed correctly though, a passage through the East River and Hell Gate is an enjoyable journey between Long Island Sound and New York Harbor, with stunning views of the UN and much of midtown Manhattan. Depending on the direction of approach, there are different easy steps to follow to make your journey as enjoyable as possible.

FROM NY HARBOR TO LONG ISLAND SOUND

Any trip northbound begins in either one of two ways: 1. check for when Northeast flood begins at Hell Gate or; 2. low water at the Battery.

Hell Gate – slack water flood

  1. If using Hell Gate current information, use Eldridge (a book all sailors should have onboard) for when “NORTHEAST Flood Starts”. Otherwise look on the Internet for when slack – flood starts.
  2. Enter the East River at the southern tip of Manhattan when Northeast flood at Hell Gate begins.
  3. The distance from the southern tip of Manhattan (the Battery) to Hell Gate is approximately 7 nautical miles so you can calculate your time to Hell Gate depending on your boat speed.

The Battery – low water

  1. Again, using Eldridge, look for LOW at the Battery.
  2. Enter the East River at the southern tip of Manhattan 2 hours after low at the Battery.

FROM LONG ISLAND SOUND TO NY HARBOR

Any trip southbound begins in either one of two ways: 1. check for when Southwest ebb begins at Hell Gate or; 2. high water at the Battery.

Hell Gate – slack water ebb

  1. If using Hell Gate current information, use Eldridge (a book all sailors should have onboard) for when “SOUTHWEST Ebb Starts”. Otherwise look on the Internet for when slack – ebb starts.
  2. Enter the East River at the Throgs Neck Bridge when Southwest flood at Hell Gate begins.
  3. The distance from the Throgs Neck Bridge to Hell Gate is also approximately 7 nautical miles so you can calculate your time to Hell Gate depending on your boat speed.

The Battery – high water

  1. Again, using Eldridge, look for HIGH at the Battery.
  2. Enter the East River at the southern tip of Manhattan 2 hours after high at the Battery.

CAUTIONARY NOTES

The times mentioned above are the earliest recommended times to enter from either direction in order to have a fair current throughout the transit. In reality, you could leave up to several hours later, but be aware that the later Hell Gate is traversed after slack, the rougher the water could be (standing waves, swirling eddies) and the more time you will need to maneuver if you suddenly find a tug and barge bearing down on you from around a blind bend in the river.

hell-gate-2As a rule, you should not transit the East River between Riker’s Island and the Southern tip of Roosevelt Island only under sail as there could be considerable commercial traffic (barges, ferries, DEP freighters) and having maneuverability around the many blind bends is critical.

It is also important to monitor VHF channel 13 for sécurité broadcasts from various commercial traffic. This can give you a heads up as to who may be entering Hell Gate and from what direction. Also, a handheld VHF is important. I have seen too many sailboaters attempt to run between the helm and down below to use or monitor the VHF while the current is taking them into dangerous waters. That is not safe boating!

east-river-maydayFinally, as with any passage planning, check the Coast Guard’s Local Notice to Mariners. Because of the UN being along the East River, the western side of Roosevelt Island could be closed due to security restrictions. This could leave only the eastern side open for travel and there is a lift bridge on that side with only 40 feet of clearance when down. Plus the current can run as fast as 7 knots on that side. Several sailboats have been dismasted on that bridge.

Google North Pacific 2

Ocean Routing Pt 1, or How do I Cross the Pacific?

With just a couple of weeks to go until I jump aboard the Clipper yacht Singapore for a grueling race almost halfway around the world from Qingdao, China to New York, thoughts turn to the North Pacific part of the race and more specifically, how do I get to California from China?  On Google Maps (or most flat maps, known as Mercator projections) the route – at first glance – looks fairly straight forward.  Simply round the southern tip of Japan and head east straight across the Pacific, passing a tad north of Hawaii on the way to California.  Unfortunately, the Earth isn’t flat, so such a route isn’t practical.

Because the earth is round (technically, an oblate spheriod) the great circle route will actually be the shortest distance between two points.  To visualize this, imagine a sphere with the top and bottom representing the poles.  A great circle would divide the sphere into two equal hemispheres.  If you did the math (which I will spare the reader here) this cut would represent the shortest distance between two points on the surface of the sphere along that line.

What does that mean for the Clipper Race on the leg from Qingdao, China to San Francisco?  It basically means that the shortest distance (great circle route) will take us relatively close to Alaska’s Aleutian Islands.  Any thoughts I initially had of idyllically sailing by Hawaii on the way to California were unfortunately just whimsical fantasies.  Instead, it will be a cold slog through the North Pacific at a time when storms race across the ocean from Japan and even Siberia to Alaska.

Having realized that late last year, I had begun to have second thoughts.  Do I really want to be sailing across the Pacific at a time when winter gales could easily bring cold, driving snow or sleet?  And, not just for a couple of days, but potentially for weeks at a time.  Cold, wet snow and slush and 30-40 ft waves washing across the deck with no place to hide above, and no heater down below.  Where is the fun in that?  When I have those second thoughts, I try to remind myself that I’m taking on the challenge of a lifetime and it will be an experience that I will cherish for decades to come.  As Sir Robin Knox Johnson is wont to say, “more people have climbed Mt. Everest than sailed around the world.”  Then again, perhaps I just need to take a more zen-like approach to it and repeat over and over, “cold is just a state of mind.”

It’s not just the Great Circle Route

Although the great circle route is the optimal route for crossing oceans, there is actually much more to plotting a route across the North Pacific then just following the great circle.  For sailboats, weather plays a large role in ocean routing.  Being found under a high pressure system with associated sunny weather, can typically mean little to no wind.  Not the best conditions if you’re trying to win an ocean race.  Conversely, being stuck under an intense low pressure system can mean gale or hurricane force winds with reduced (or no) sails and being tossed about to-and-fro at the mercy of the weather gods.  That’s also not ideal for winning a race.  The happy medium lies somewhere in between, and here is where planning is essential both for winning a race or a podium finish and for safety.  For offshore racing, optimal route planning takes into account the great circle route as a first step.  Then, prevailing or forecasted ocean currents should be taken into consideration, and last but certainly not least, forecasted weather.

The race in detail

Leg six from Qingdao to San Francisco can be broken down into three sections for route planning.  The first is from Qingdao, down through the East China Sea to the southern tip of Japan.  The next section is along the coast of Japan and the Eastern North Pacific to roughly the international dateline.  The third and last section is the Western North Pacific and offshore the U.S. coastline to the Golden Gate bridge.

On the first section, leaving Qingdao and sailing through the East China Sea to the tip of Japan, the route is fairly straight forward.  Just head southeast towards the southern tip of Japan and avoid any islands along the way.  The currents in the East China Sea are primarily wind-driven and thus do not hold much tactical advantage.  As far as the weather is concerned March tends to be the busy time of the year for lows to develop near the south coast of Japan.

Rounding the southern tip of Japan, the route follows the Japanese coast midway up threading between various islands southwest of Kyushu and later, south of central Japan.  Flowing along the coast of Japan is the Kuroshio current, one of the largest ocean currents in the world. The Kuroshio current typically flows around 3 knots, but can flow at speeds of 4 knots or more in some places.  Because of the swift speeds of the Kuroshio current (it can travel 75 miles or more in a day), it can play a major role in gaining a tactical advantage in the race up the Japanese coast and out into the eastern portion of the North Pacific. Finding the swiftest part of the current can quickly spring a boat into a decisive lead.

The Kuroshio current carries warm water up from the equatorial region, and because of this, it has a major impact on the development of weather systems over the Pacific Ocean, in particular in the early spring, when Mongolian cold weather meets the warm waters of the Kuroshio current.  The area south of Japan is one of the areas where low pressure systems (i.e. rain and wind) develop before the storms generally move northeast towards the Bering Sea and Alaska.  Because of the swiftness of the northeasterly flowing current, strong winds out of the north can quickly lead to steep waves that are bone-jarring as the boat drops off the back side (wind against tide tends to form rather steep choppy waves).  Trying to sail through these types of waves can also slow the boat down considerably, so finding the balance between riding the current and optimal wind angles become critical.

Midway up the Japanese coast, the great circle route begins its long arc across the North Pacific crossing the International Dateline at around 44° North.  However, during March winter conditions tend to prevail (i.e. strong storms!) which will demand a more southerly route with us likely crossing the meridian around 40° N.  Through much of the Pacific crossing, the currents are generally easterly with no real difference in location or speed (the North Pacific Gyre is relatively constant here).

The trick on this section of the race is to find the sweet spot between not going too far north and risk being beset by fierce Pacific storms or going too far south and being becalmed by the Pacific High.  As the synoptic chart (large-scale weather chart) below shows, lows (L) with hurricane force winds can develop around 44° N, while the Pacific High (H) and associated light-to-no winds can reach up to 38° N.  Successfully threading the way between these type of moving weather systems in mid- to late-March will be the key to either gaining or maintain a leading position.

After crossing the International Dateline (which separates the Eastern and Western Hemispheres), the sailing route will likely continue due east for a bit before beginning to dip south.  Weather patterns on this side of the Pacific tend to be more stable and are really determined by the Pacific High (technically known as the North Pacific subtropical anticyclone) which tends to be a relatively stationary weather system over the mid-North Pacific Ocean.

Roughly, 300 miles from the US coast, the California current (which is the eastern component of the North Pacific Gyre) runs down the western coast at a relatively slow speed of about half a knot. As with other currents associated with the North Pacific Gyre, eddies or counter-currents can spin off the main current stream.  While generally weak, they flow in the opposite direction of the direction you want to go and if caught in them, could slow the boat down enough to drop back in race standings. Weather-wise, there is little to worry about on this section as the fierce Pacific storms are well north of our track, so our route will likely follow rather closely to the great circle route until we finally sail under the majestic spires of the Golden Gate Bridge.

How Do I Get from A to B?

RYA Training ChartI recently returned to Gosport, UK to continue my training for the Clipper Round the World Yacht Race.  This time, the training was shore-based and included, in a short summary, various theory courses including navigation, meteorology and rules of the road.  The course is part of the RYA (Royal Yachting Association) requirements to eventually obtain the Yachtmaster certificate of competency.

Navigation, meaning how to get from point A to point B without any issues or mishaps; rules of the road, meaning when two ships cross, who has right of way; and meteorology, meaning knowing when a storm or clear weather is likely to pass over you.  Add a smattering of learning what various buoys in the water mean and what lights different boats may have at night or shapes they may hoist during the day, and that pretty much sums up our week of study.

Beyond the 10 second “elevator” summary above, the details are much more intense.  As they say, “the devil is in the details,” but if you are navigating through unknown coastal areas with tides and winds pushing your boat to-and-fro, the details can mean the difference between arriving at a harbor safely or ending up on the rocks!

Having flown into Heathrow from NYC, I spent a long three hours in the airport immigration line thanks to a “slowdown” (gotta’ love those unions!).  Nevertheless, I eventually made it to Gosport albeit a couple of hours late for class.  The first few days were spent learning navigation, with the class typically running from 9 am to 5 pm, then several hours of homework afterwards.

At first glance, it may sound simple to go from Point A to Point B.  Just look at a chart (nautical term for a map) and point your boat in the direction you want to go.  However, if the tides are flowing 1-2 knots perpendicular to you and are pushing you off to the side, where would you end up in an hour or two hours’ time?  Now, add to that winds pushing the boat sideways as well (leeway) and you have three different forces that you need to account for (direction sailed to destination, tidal direction and leeway).  But, lest you think that is all, you also have to take into account the variation between True and Magnetic compass directions.  Charts are always oriented to true north or the North Pole, while compasses point to the magnetic north which can be offset from the North Pole by a considerable amount depending on where in the Northern Hemisphere you are.

Ah, but in today’s modern world, we have GPS which tells us where we are all the time.  What need do we have for all this plotting stuff?  Well, setting a GPS waypoint (a “goto” position on a chart) will enable you to determine the direction you want to go, but it will not tell you the direction you need to steer to get to that direction.  If the tide is pushing you sideways to the right, you will need to steer a little more to the left to compensate.  If the wind is also pushing you a tad to the right, then you will again need to steer a tad to the left to compensate.  How much do you compensate, or what is the course to steer?  Ah, that is where all the plotting and calculations come into play!

To calculate the course, you must first know the time you will be leaving on a particular journey (or passage).  Then, for the area you will be travelling, you will need to look at tide tables for that particular day and time.  Once that is determined, you can use tidal charts or a tidal curve to determine the direction and speed of the tide (called set and drift).  Then, in plotting your course, you will add that to the chart to determine the actual direction you need to steer to get to that position.  At first, it can sound complex and confusing, but with enough practice, it does get easier.

After working through numerous, navigation exercises for several days (practice, practice, practice), it was on to learning about navigational buoys, rules of the road and meteorology.

Navigational buoys are the traffic signs of the waterways.  They can tell you where the main highway or thoroughfare is (the channel), whether it’s safe to pass to one side or the other of the mark, and where hazards may be.  Although there are a number of different buoys or marks, they basically fall into three types; lateral marks which mark channels (red and green buoys), cardinal marks which mark where water is too shallow to go (very rare in the U.S.) and special marks which are used to mark underwater cable, pipelines, sail racing areas, etc.

Rules of the road basically refers to the ColRegs also known as the International Regulations for Preventing Collisions at Sea.  This area is a tad more intensive, but necessary to learn if you are going to be driving a boat anywhere in the world.  Basically, as a captain of a boat, you are responsible for that boat and the safety of the crew and others as well.  As part of learning/memorizing the ColRegs, you need to know how to identify different types of boats by the lights they show at night.  This is important because knowing the type of vessel will determine who has right of way.  In a crossing (or overtaking) situation, sailboats when sailing generally have right of way (technically called the stand on vessel), but larger vessels including those that cannot maneuver as easily generally trump sailboats.

It never ceases to amaze me in New York Harbor how many sailboaters adamantly exercise their “right” to go where they want, cruise ship, tug and barge or Staten Island ferry be damned!  This is stupidity taken to the extreme as those ‘skippers’ are putting the lives of their crew at risk.  If they can’t be bothered to learn the rules of the road, then it at the very least, learn the one maxim, “might is right.”  The bigger the boat and the more difficult it is to maneuver, the more it takes precedence over a smaller more agile vessel.  The photos below from Cowes Week are a good example of the consequence of ignoring this maxim!  And, while I have the bully pulpit, if a sailboat is motoring (engine on and engaged) it is then regarded as a motor vessel, not a sailboat.  Plain and simple.  But, I digress 🙂

   

The last day of our theory course was spent studying meteorology.  This was actually a tad disappointing as it covered very basic information (for me).  In the Northern Hemisphere the jet stream moves from west to east, and low pressure systems rotate counterclockwise (anti-clockwise for the Brits) while high pressure systems rotate clockwise.  What does this mean in practical terms?  Because the jet stream moves from west to east, any weather front will generally move along that direction over U.S., Canadian and European waters.  That helps to know where storms could come from.  And, if it is a low pressure system, depending on where that system is in relation to you, wind directions can be forecasted.  Wind speeds can also be forecasted by the pressure gradient (difference in atmospheric pressure).  The tighter the pressure gradient, the stronger the winds and vice versa.

All too soon, the week ended and it was back to Heathrow and on to New York.  I think rather than watching a movie on the plane, I’ll work through some navigation exercises. Now, where did I put those tidal diagrams …