Posted by admin on February 16, 2012 under Bareboat Charter, Coastal Navigation, Crew, Skipper, weather | 
Tides and Tidal currents
Tides and tidal currents came to mind today as I strolled along the harbor’s edge watching the behaviour of some sailboats racing. Remembering a recent race regatta series I participated in in the Auckland New Zealand harbor last winter also brought up this topic of tides and tidal current. In one race in the series, we were racing back up the harbor while the tide was ebbing (going out). Consequently, the current was racing in the other direction. Our tactic was to stick to the sides of the harbor as close as possible where the current is the least. Unfortunately all the other boats knew to do this as well and this created a pretty big mess of all the fleet tacking on top of each other. “Starboard” was the call of the day as each boat established their stand-on position over the other. Every now and then one boat would break out and try to brave the current instead of the tacking mess only then to rejoin the fleet as they were dragged backwards. It was pretty exciting actually, although our skipper was stressing a little.
There was pretty much nothing we could do except tack tack tack and keep a very diligent watch for traffic ducking and tacking to give way when required. The skippers were trading expletives with each other across the water more in this race than I’d seen in any other. LOL
How Tidal Flow Works in a Harbor
In a channel, current will run strongest in the deepest parts typically towards the center, unless there is a bend in the channel then the current will run strongest on the outsides. Just think about the last time you watch water flowing in a river to visualize. So your best bet when trying the go against the tidal current is to hug close to the sides and on the inside turn if possible. At an extreme case I had a friend in Sydney harbor who won a race by waiting out the worst part of the tidal current by throwing down the anchor. Not sure if that’s against any official race rules but it’s pretty funny.
Also take note that current flows “relative” to the tide period but slack water does not necessarily match high and low tide times especially in harbors. Tidal current is determined by the local effects of the upstream harbour shape and weather, not just the sinusoidal tidal period. That comes as a big revelation to some. In fact, I physically had to show my skipper prior to the start of a race one day last winter.
Real Example of Tides in a Harbor
Observe the following which is Auckland New Zealand harbour, one of the more heavily raced harbors in the world.
Chart of in Auckland Harbour
Now look at today’s tidal period;
Sinusoidal Tide in Auckland Harbour
- High tide: 3:52 am
- ½ tide at 6:55 am ebbing (going out)
- Low tide: 9:57 am
- ½ tide 1:07pm flooding (coming in)
- High tide: 4:16 pm
- ½ tide: 7:22 pm ebbing (going out)
You might assume that minimum current occurs at high and low tides ie 3:52 am and 9:57 am and 4:16 pm while the max current occurs at ½ tides at 6:55 am and 1.07 pm
But now look at today’s current predictions:
Tidal Current in Auckland Harbour
- Min current flow was at 3:15am (45 minutes before high tide)
- Max current flow ebbing was at 5:16 am (1 hour 39 minutes before ½ tide ebbing)
- Min current flow was at 8:15 am (1 hour 45 minutes before low tide)
- Max current flow flooding at 10:54 am (2 hours 13 minutes before 1/2 tide flooding)
- Min Current flow at 3:51 pm (25 minutes before high tide)
- Max current flow ebbing at 5:57 pm (1 hour 25 minutes before ½ tide ebbing)
A quick analysis of this shows that the current matches in time the flooding tide more than the ebbing tide. This empirically supportis the statement above about how the upstream shape determines the current flow out.
As a specific example, lets say it is 8:30am on the day shown. From a tidal analysis you would think that the tide is ebbing and so an early morning race out of the harbour you’d probably stick to the centre of the channel. However the prudent sailor doing a current flow analysis would see that the current has already turned to flood and would stick to the sides of the channel. All things else being equal, prudence would win.
In General:
- Don’t assume that the current is slack at high and low tides
- Stick to the edges of the harbor when going against the flow
Navionics Electronic Chart
In this article I used the Navionics iPhone app. I pressed and held my finger over the diamond shaped T to get the tidal info and the diamond shaped C to get the current info. When you have such an electronic chart, look for these diamond T’s and C’s scattered through out. On iPhone and iPad simultaneously push the home button and the power button to get a screen shot.
Tide and Current icons on an electronic navigation chart
Rule of Twelve
While we’re on the tidal topic I might as well discuss the rule of twelve regarding a sinusoid. It’s a good general piece of knowledge to know since tidal heights generally follow a sinusoid shape (except in weird tidal places in the world like the Solent in England where two high tides occur about 1 hour apart).
In the first 1/6th of the time between high and low tides, the height changes by only 1/12th of the full amount
In the next 1/6th the height changes by an additional 2/12 (=1/6)
In the 3rd 1/6th ie half tide the height changes by an additional 3/12 (1/4)
Adding 1/12 + 2/12 +3/12 = 1/2. So at half tide, the height has changed to ½. That makes sense but looking back and assuming a diurnal tide (6 hours between high and low), in the first hour the height has only changed by 1/12th. That’s insignificant. At the end of the 2nd hour the height has changed by a total of 3/12ths = ¼. That’s still pretty insignificant.
What this means is that if you’re relying upon the tide to increase the depth in a shallow area, then even with a 10 ft (3m) tide, 2 hours after low tide, it has only come up 2.5 ft (0.75m). Best you wait until half tide at least when the ½ of the height change has occurred (5 ft (1.5m) in this example).
NauticEd Coastal Navigation Sailing Course
For a full discussion on tides, tide table, how tides work and why there are two tides in one day when the earth and moon only rotate relatively about each other once per day, take the NauticEd Coastal Navigation sailing course. You’ll also be able to brush up on your navigational skills which isn’t at all a bad thing.
Coastal Navigation Sailing Course
This article was written by Grant Headifen, Educational Director for NauticEd Online Sailing School
Posted by admin on January 30, 2012 under Bareboat Charter |
If you ever thought of checking off a dream sailing vacation in Tahiti from your bucket list this is the opportunity to get that one taken care of.
Announcing the 2012 NauticEd Post Graduation Sailing Adventure
If you’re a NauticEd Bareboat Charter Master or plan on being one before June next year, then come celebrate your graduation by sailing with us in our Post Graduate Sailing Flotilla to one of the world’s most beautiful and tropical locations – Tahiti.
Sailing Vacation in Tahiti
Tahiti sailing is amongst the very best in the South Pacific. Tahiti is blessed with some of the most beautiful islands in the world with many high volcanic islands that drop dramatically into the ocean enabling sailing right alongside the coastlines and into protected bays.
Personally, I have lead dozens of successful and extremely fun flotillas world wide and I’ll be on hand to serve as your Fleet Admiral throughout the flotilla. I co-authored the NauticEd Bareboat Charter Clinic and really know how to put together an event like this so that every day is packed with fun including water and beach games and competitions but also so that everyone feels looked after and safe.
Program includes:
- Week long sailing charter in Tahiti
- Daily activities including water and beach bound competitions
- Mini sailing regatta
- Treasure hunts
- Your selection of vessels (subject to availability)
- Professional Fleet Admiral to lead, guide and assist
- NauticEd Flotilla tees and hats for Captain and made available for Crew
- Sign off on Bareboat Charter Practical Proficiency Verification Certificate
- Prize giving event at conclusion for fun weeklong happenings including first to spot a whale and the infamous BLUE and BLACK DUCK awards
- Full event management
- Airport pick-ups and drop off in Tahiti
- Personalized DVD of the event
- FREE NauticEd crew course for all your crew members
Shortly we’ll be all the details however, if you want to guarantee a reserved spot on this flotilla, contact
NauticEd Sailing School as quick as possible to get a place in the queue. We’ll only take a max of 5 boats in the flotilla.
The adventure starts June 16th.
Posted by admin on January 8, 2012 under Bareboat Charter, Crew, Rules of Right of Way, Sail Trim, Skipper |
This is the 2012 New Years Resolution Sailing Tip
This issue’s sailing tip is a pretty simple one. It will lead to you having more valuable practical sailing experience than you’d ever imagine. And it fits nicely in with any new years resolutions you might be considering.
When I lived in Austin Texas, I raced a lot with the local sailing club there on Lake Travis, an inland small lake. And I have to admit that much of my finer technical sailing knowledge came from those many regatta races.
When a sailboat racing next to you is inching ahead moment by moment you learn quickly the importance of accurate sail trim. And talk about drilling the rules of the nautical road – wow when you’re on collision course with dozens of yachts you’ve got to know the rules.
Here’s the tip: Join a local yacht club this year.
At NauticEd we REALLY believe that practical sailing experience is one of the keys to becoming an excellent sailor (of course we’re making a big assumption that you don’t have a goal to be a crappy sailor).
A bit of History: When we designed the NauticEd sailing certifications, we consulted with dozens of sailing instructors and many of the world’s largest charter companies. With out any hesitation, they all rated practical sailing experience as a must have to becoming a competent sailor (durh). When we looked at every other global sailing certification, none required practical sailing experience as a prerequisite to gaining the certification. That’s a bit strange we thought because in this digital age, it’s easy to write an algorithm that can combine theory knowledge and practical experience (well not that easy but you get the point).
Then we looked at the scuba diving industry and the scuba certifications. We found that the theory education was excellent but practically – if you can barely swim, you’ll still end up with a certification. Still strange! The scuba magazine editorials are full of complaints about new divers banging into the protected reefs because they can’t do the most basic buoyancy control.
When it comes down to it I guess, most certifying companies are more interested in the $ than the true competency of the student. Thus we decided to set the competency bar high so that the charter companies could truly trust a experience and theory based certification.
So here’s the big “but” that people ask us all the time then.
“But … how do I get sailing experience when I don’t own a boat”.
Well… in virtually every city with a sailing waterway there is a yacht club.
- Joining a yacht club is pretty simple and relatively inexpensive for the return you’ll get. Costs range from $40 to $80 per month. And if you own a boat, many times the marina fees are less expensive than a regular marina.
- Some clubs are very racing focused some are not. I’ll maintain however that even if you’re not a racing type person, racing experience will improve your cruising sailing skills vastly. Racing is like learning a language by immersion.
- Yacht clubs are highly social and so you’re going to meet a lot of very cool and interesting people who will become your friends. Throw away the preconceived notions of the stereotype snooty stuffy yacht club and just join one and find out for yourself.
- Yacht clubs many times have a nice pool for the kids to hang out in and they will get to hang out with other yachting type kids. A vast improvement from learning life skills at the mall.
- Yacht clubs organize weekend sailing trips away. These are usually very fun flotilla events. Here you can learn a lot of overnighting and anchoring skills.
- Occasionally yacht clubs will also organize a bareboat charter sailing holiday to places like the Caribbean, Mediterranean or the pacific islands. This is a great opportunity to join in on the safety of a flotilla.
Some people think that if you don’t own a boat, then what’s the point of joining a yacht club. However, if you don’t own a boat, then you should definitely join a yacht club. Here’s a big fact. Virtually all boat owners are desperate for crew for either racing or cruising events. This is proven by the dozens of post-its on the yacht club notice board from skippers looking for crew.
Typical Yacht Club Notice Board
So – this year, join your local yacht club. Put your name up on the notice board that you’re willing to crew. Commit to some regatta race series. Do some boat jumping to find the boat/crew/skipper that you like. Make some friends. Get lots of sailing experience and most importantly, fill out your free NauticEd electronic sailing logbook. As with above, your logbook is the single most important thing that the charter companies look at when you are trying to charter a boat.
And one more comment – years ago when I ran a large yachting membership program, the biggest reason that people dropped out was that they did not have friends to go sailing with them. A mistake that I made was that we should have promoted our boat owning members to also join a yacht club. There, they would have found plenty of new friends to go sailing with, from the exact same notice board mentioned above. If you own a boat – join your local yacht club this year.
Happy Sailing Experience!
Posted by admin on January 6, 2012 under Bareboat Charter, Coastal Navigation, Rules of Right of Way, Skipper |
Where were you over the holidays? Sailing?
If you tried to email us over the holidays, you would have gotten a polite “out of the office notice”. We were busy catching up with our Canadian friends who have been sailing the world with their three kids for the past four years on a 42 ft PDQ Antares Catamaran. Early last year we meet up with them in New Zealand in the Tasman Bay (see the video in New Zealand). This year we meet with them in the inland water ways around Brisbane and the Gold Coast of Australia. Sailing with the Ellsay’s on Stray Kitty is a real insight to the lifestyle of world cruisers. They’ve certainly got it down and watching the kids in action with the lines and fenders was pretty impressive. This adventure was particularly interesting because of the intercoastal navigation issues in and around all the waterways. So here, I thought I’d relate a few stories as highlights of the issues and proof that both theory and practical knowledge is king.
Waterways south of Brisbane
One beautiful sunny afternoon we were anchored at a place called Jumpingpin. We went for a walk along the beach and came across a uniquely Australian experience by encountering a group of wallabies hoping across the sand.
Jumpingpin - A popular day stop (so long as you anchor properly)
After a nice stretch along the beach we returned to the boat just in time to beat an approaching thunderstorm. And in Ausy fashion, this one turned out to be a real beaut. About the time winds reached a peak of 40 knots we realized the washing was still on the lifelines and my bald head got a real pelting with the huge sideways rain drops as I brought in the now drenched washing. All the while that I was doing this, Chis, the skipper was pulling out fenders ready to fend off any of the at least ten yachts that were now dragging anchor.
To make matters worse, the tidal range in the area is around five feet. This creates particularly strong tidal currents in the narrow waterways. As the thunderstorm pelted us, the tidal current had risen to about 5 knots and was flowing in the same direction as the wind. This put huge forces on the anchors and it was pretty hair raising to see how fast the boats that had drug anchor were flying by. As an observation, almost all of the boats that had drug anchor and were now trying to reset them were using CQR plough type anchors.
The Dreaded CQR Anchor. Leave it at home.
Stray Kitty uses a Rocna roll type anchor and it held fast. Of course, in typical style of many boaters, the scope used was also way to low on boats that were dragging. And so we were able to watch the comedy of anchoring errors unfold in front of us. In reality there was no comedy. Some of the dragging boats were coming way too close, way too fast.
Boats anchored at Jumpingpin. Anchor scope too small and CQR Anchors caused dragging.
Next, one of the boats that re anchored abeam of us did it a bit too close and so as the current reversed later that night we began to come dangerously close. We elected to raise anchor and reset further out into the channel. However this presented quite a challenge with site selection. The wind was flowing in one direction whilst the current was in the other, and, we knew the current would again reverse before we awoke. Couple this with the difficulty in determining distance at night from other boats made us both glad of our previous anchoring experiences and knowledge. The worse scenario consequence of dragging anchor in the night and being washed out of the protected albeit high current waterway into the huge breakers coming in thought the cut was not one I wanted to spend to much time thinking about.
Another challenge was the markers. First off, Australia abides by IALA-A system which is opposite to the America’s IALA-B system of navigational marks. I.E. red right returning doesn’t work – it’s green on your right when returning. And in the USA the intercoastal water way fairly consistently uses green to seaward along the full length of a waterway with specially marked intercoastal day marks. IE heading from New Jersey past Florida and onto Texas you would keep green intercoastal daymarks on your left. In Queensland, they don’t seem do that and so the green and red swap inconsistently up and down the waterway.
Red Day Marker
Sometimes the red and green swap sides, some times they don’t. They seemed to use the yellow special purpose marks to designate a channel intersection rather than a preferred channel marker with red over green or green over red that is used in the USA.
Special Purpose Marks designating a channel intersection
Twice we were caught out nearly heading onto a sand bar because the day mark swapped over. The Australian navigation system also uses cardinal marks. Being able to read these quickly kept us out of trouble when it came to isolated dangers.
East Cardinal Mark (Safe Water to the East of this mark)
On top of all that, sand bars move and so your highly relied upon GPS map showing the exact position of the day marks can’t be trusted. When sand bars move the local coast guard move the day marks to remark the proper deep channel. So you can be looking at your GPS telling you that the channel is in one place when the marks tell you some thing else. Which do you trust? You have to trust the day marks.
Waterway Chart. Even with GPS don't rely on the chart. Follow the day markers.
Twice we had to turn right angles to follow a day mark went the GPS was telling us that the depth was one foot. Of course a slow and easy pace combined with the depth sounder readings is essential. Still, when you have only two feet to play with below the keel, sometimes it’s not the greatest comfort.
We tried our best to time our sailings each day with the changing tidal current so that it would help our speed. On the day that we approached Surfers Paradise this was not the case however and our 7 knot though the water speed only gave us a three knot SOG (speed over ground) due to current. On one particular day we had to ensure that we crossed under powerlines at half tide or lower due to the height of Stray Kitty’s mast.
Under Sail (actually me just posing for the shot)
As hairy as I seem to have made the above sound, we definitely had a spectacular time visiting this area. It’s off the beaten track when it comes to top charter locations around the world and probably for good reason due to the complexity and also due to the spectacular and more popular Whitsundays area to the North.
There are two highly relevant NauticEd sailing courses to this article. The first is the NauticEd Anchoring a Sailboat Sailing Course. I’d venture to say that none of the power boats that drug anchor that day would have done so if they’d taken this course. First thing they’d have done was to leave the CQR in the garden at home and secondly they’d have understood scope a little better. Surely those people are embarrassed that they drug so badly.
The second course that would really help someone enjoy our intercoastal venture as much as we did would be the Coastal Navigation Sailing Course. This course teaches in depth the navigation marks of both IALA-A and IALA-B systems including cardinal marks.
The other comfort to the whole trip was having very experienced world cruisers on board. After a hard day of tidal currents, thunderstorms, crazy reversing navigation day marks and shallow waters we were rewarded with gourmet type dinners under the southern sky. The crew of Stray Kitty, after living on their cat every day for the past four years, did not sacrifice food quality one bit and were even able to whip up a birthday cake for me on the 31st.
The Crew of Stray Kitty (next to their Christmas Tree)
Other tasty delights on the menu were kangaroo, pork roast, shrimp pasta, steaks, roast turkey, gammon (cooked in the oven on board), plenty of salads and cookies. Some great Australian and new Zealand wines were poured on top of the above in the warm southern hemisphere summer over the Christmas and 2011/2012 new year.
Christmas Dinner Table Setting Aboard Stray Kitty
Thanks to Stray Kitty and her Crew!!!!!!!!!!!
Christmas Dinner with Alexandra, Andrea, Grant, Ryan, Christine, Cari, Chris, (Vanessa photographer - Nikon D3100) on Stray Kitty - a 42 ft PDQ Antares Catamaran
Posted by admin on October 31, 2011 under Bareboat Charter, Crew, Maneuvering Under Power, Skipper, Storm Tactics |
Docking a boat on to an end-tie or tee head with a strong wind blowing you off requires some knowledge on how to do it and it’s one of those things that you SHOULD practice for WHEN the time comes.
Trying to just sidle up along side like you might do in a no wind condition or where wind is blowing you on to the dock is just not going to work.
Fortunately, there are some simple ways of doing it.
(1) Motoring forward up to the tee head directly into the wind.
Have dock lines prepared and cleated to the forward and aft dock side of the boat.
NOTE: Make sure that the dock lines are run outwards underneath the life lines first then back onboard over the top of the line lines. This ensures that when the line is deployed, it will be clear of the life lines. Since this is usually a crew member doing this, it pays to physically show the crew member when you are out away from the marina if you’re not sure they will do it correctly. Running them inboard and over the lifelines can create a huge havoc at the wrong and crucial time.
Approach the tee head near perpendicular but at an angle so that it makes it as simple as possible for the crew member to step off the boat as far forward as possible. As you reach the tee head the crew member will have to step off the boat and onto the dock. This requires a little dexterity on the crew member’s behalf and good throttle work on your behalf to not hit the dock yet get the crew member close enough with out jumping. Since you’re headed directly almost into wind, you’ll have afforded some time with the bow at the dock so that the crew member can take their time carefully stepping off the boat and onto the dock.
The crew member now cleats the dock line to the dock cleat in the direction of where the aft of the boat will sit using about ¼ of the boat length of line between the two cleats.
Now comes your part. Turn the wheel all the way to the stops to the non-dockside side of the boat (tiller to dockside side) and engage forward gear. This creates a sideways force on the rudder and will push the stern of the boat to the dock. Adjust the throttle to over come the windage force on the boat.
DOCKING A SAILBOAT INTO THE WIND
(2) Motoring in reverse up to the tee head directly into the wind.
This method works especially well when the boat has a swim platform and walk through transom.
As above, have dock lines prepared. Then back up to the tee head.
NOTE: You’ll learn in the NauticEd Maneuvering a Sailboat Under Power online sailing course that a boat’s stern facing the wind is an extremely stable position and you will not get bullied around by the wind. You’ll also learn that backing into the wind is extremely easy. If you haven’t already, take the NauticEd Maneuvering a Sailboat Under Power online sailing course.
The crew member steps off the boat holding the aft dock line when the stern is close enough and cleats the dock line to a dock cleat that lies in a direction more aft of the boat in its final resting position. Again about ¼ of the boat length of dock line should be allowed between the aft cleat and dock cleat.
Turn the wheel all the way to the stops towards the dock (tiller pointing away) and engage forward. This will swing the bow of the boat in towards the dock against the wind. Another crew member can toss the forward dock line to the crew member on the dock to aid. Or if the 1st crew member is able they should take a long forward dock line with them when they stepped off the boat originally.
DOCKING A SAILBOAT INTO THE WIND
Either of these methods can get you docked safely. And, practiced, a skipper could do all the above solo.
Practice both of these a few times and when the real moment comes, you’ll be looking like a pro. Rather than a…
This docking a sailing boat tip was written by Grant Headifen , Director of NauticEd. NauticEd offers an excellent Maneuvering a Sailboat Under Power online sailing course as well as many other online sailing courses.
Posted by admin on October 3, 2011 under About NauticEd, Bareboat Charter, Celestial Navigation, Coastal Navigation, Crew, Skipper |
The posting here is not a course in celestial navigation by any means. However it’s meant to simplify a few principles for you so that you’ll at least have some sort of celestial orientation. And… perhaps it’ll inspire you to learn the aging art.
This was written by Grant Headifen, Educational Director of NauticEd. NauticEd provides online sailing courses and Sailing Certifications accepted by charter companies worldwide.
Latitude: In the northern hemisphere, finding latitude is simple using one of the greatest gifts to human kind – The North Star. What ever angle the northern star is at from the horizon, that’s your latitude.
Imagine you’re an ant sitting on the top of an apple looking at a spot directly above you on the ceiling then the spot is 90 degrees from the surface you’re standing on. If you’re standing half way around the apple then you’d barely see the spot but it would be horizontal to the surface you’re standing on and so the spot would be at zero degrees. And if you were ¼ of the way down the apple then the spot would be at 45 degrees etc. ie the northern star is the spot on the ceiling to us.
You can also find latitude using other celestial sightings but they involve table lookups and are slightly more complicated. Not meant for this post and also note that there are a few more complicated variables not taken into account during this simplistic explanation like the height of your eyeballs above the earths surface etc etc. But at least you’ve now got the principle.
Longitude: Now this is a fun one and in an incredibly easy principle. But years ago (early 1700′s) while the principle was easy then the execution was difficult. Read on to see why.
The earth rotates through 360 degrees in 24 hours. That’s 15 degrees per hour. By convention, when the sun is at it’s highest point in Greenwich, it is noon in Greenwich. That means that at a place that is 15 degrees to the West of Greenwich the sun will be at it’s highest point one hour later. Six hours after Greenwich the sun will be at it’s highest point somewhere in over the USA and 12 hours later the sun will be at it’s highest point in New Zealand.
Animation of time zones
So if we know the time in Greenwich and sun just reached its highest point where we are then we can calculate our longitude.
Lets do a few examples. If it is 6 pm in Greenwich and the sun just peaked overhead here, then I am 6 x15 degrees to the west of Greenwich which is 90 degrees West which is right near St Louis Mo.
If the sun peaked overhead in Los Angeles what time would it be in London.?Well LA is 118.15 degrees West (from Google earth). Divide that by 15 degrees per hour and we get 7 hrs 53 minutes. Now since the times zones are created in bands this would round up to 8 hours. Thus it would be 8pm in London.
You’re sailing in the Greek islands in the Mediterranean and a little bird just told you your latitude is 34 deg 54 minutes north but failed to tell you the longitude. Fortunately you have your handy sextant and just as you take a shot, the sun just reached its apex overhead. You look at your watch and the local time is 12:10:48 pm. Where are you?
Since you’re in time zone B you are 2 hours ahead of Greenwich. Thus the time in Greenwich is 10:10:48 am. And since the sun peaked just now (=noon) then you are 12:00:00 minus 10:10:48 = 1 hour 49 minutes and 12 seconds from Greenwich. Putting this into decimal time this is 1.82 hours. Multiply this by 15 degrees per hour and we have 27.3 degrees East or 27 degrees, 18 minutes East.
You’re in the harbor north of the town of Kos on the Island of Kos.
That was incredibly easy, so why all the hoopla back in the 1700′s? The King of England even offered up a ₤10,000 reward to anyone who could solve the issue of Longitude. The above math was well known but the issue was telling the time. No one could accurately keep time at sea. After 27 years of work on the project, John Harrison, finally invented the Chronometer more commonly known as the watch. The watch was not susceptible to the sudden crashes of waves at sea and thus kept proper time.
James Cook on his second trip around the world in 1772 sailing on Rendezvous, took Harrison’s watch with initially much skepticism. Stating that he’d give it a try. After six months at sea, Cook stated that the Chronometer would almost certainly become the way of the future for Navigators. Cook then went on to reposition many of the Islands in the Pacific including Tahiti, his favorite island. His map of New Zealand astounds people even today with its accuracy.
Again there were a few simplistic assumptions taken in that explanation. But now, at least you understand the principle of longitude determination from a noon shot of the sun. You can also determine your latitude from a noon shot of the sun as well using tables and a bit of math. Again beyond this posting.
If you’d like to delve deeper into these topics, NauticEd provides an Introductory Celestial Navigation Sailing Course, or maybe you’re just happy with your handy boring ol GPS.
Posted by admin on September 14, 2011 under Bareboat Charter, Crew, Maneuvering Under Power, Skipper |
Here’s a question from a student regarding docking a sailboat after they took the Maneuvering Under Power Sailing Course
>>>>>>>
Hello Grant,
I have a question in reference to the maneuvering under power:
Under the excersice end ties #3, wind from behind, once you have backed the boat to the dock and secured the stern spring line, should the wheel be turned toward the dock and throttle into forward to bring the bow to the dock?
Thanks,
Excellent course!!!
Jose
Happy Sailing.
>>>>>>>>>>>
Jose,
You’re absolutely correct.
Here is a vector force diagram to match. Actually, as you can see, you could do it with out turning the wheel to the dock but the resultant torque (turning moment) would be reduced. Turning the rudder creates extra turning moment. It doesn’t really matter which direction the wind is coming from with this method. Altho if the wind was high and blowing you off the dock. I would do the front spring first, then drive forward with the wheel turned away from the dock.
Cheers
Grant
Docking a Sailboat
Posted by admin on August 8, 2011 under Bareboat Charter, Coastal Navigation, Crew, Rules of Right of Way, Sail Trim, Skipper |
How to Heave To
The books simply say to tack the boat and leave the head sail cleated to windward and turn the wheel all the way to windward (tiller to lee). While that’s correct, there are a lot more things to think about to pull it off correctly. This article is part of the training in the Skipper Sailing Course and is written by Grant Headifen, the Educational Director.
There are a few reasons you might want to heave to.
- Lunch, simply taking a rest, or instructor debriefing
- Storm Tactics and Reefing
- Man over board recovery
- Boarding by another vessel (ie, crew change during a race, or law enforcement safety inspection)
A Cool Trick about Heaving to!
The first thing to think about is (if you can) lie in a heave-to position so that your boom is on the port side. Why? So that you’re technically sailing “on starboard tack”, putting you in a more advantageous stand-on position with regard to the Navigation Rules vis-a-vis other sailboats “on port” tack. Wouldn’t want to disturb our lunch now would we? It’s not a big deal but just something most people may not have thought about.
What is Heaving To?
When you are successfully hove-to, your sailboat will be in a stable situation with the mainsail and headsail still up. Your forward speed will be minimal and you’ll be sliding downwind slightly. This makes it an ideal strategy for the situations above. Essentially you’re under full sail but nearly stopped! Cool eh?
How Heaving to works
The mechanics of the heave-to situation is that the forward speed of the boat has dropped to a minimum because the head sail is back winded (aback) and the main sail has been eased out far enough to reduce nearly all of the forward driving lift on the sail. The backwinded head sail creates a large turning moment on the boat to turn it downwind. As the boat turns downwind however the boat tends to pick up a little speed. As the boat picks up a little speed, the windward locked wheel causes the rudder to turn the boat back upwind, killing off the speed. It creates a little see-saw action. You can adjust the see-saw action by adjusting the set of the headsail, the mainsail, and the rudder angle. Each boat will see-saw a little differently in differing wind conditions and due to the distances of the rudder and the headsail center of pressure positions around the hydrodynamic pivot point of the vessel. Once the boat is settled, by making small adjustments to the angle of the rudder, the amount the mainsail is eased, and by the “depth” or flatness of the headsail, a skilled operator can make very useful adjustments to the exact way in which the boat is lying to the wind and seas. Practice practice practice! When that storm comes, you’ll be glad.
How to Heave To
Once you’ve got it down, you’ll enjoy having this little skill under your belt but you’ve got to practice it a few times. To enter into a hove-to position, if practical, start out on a on a port tack with the headsail sheeted in tight. Tack the boat slowly onto a starboard tack (bleeding off some speed while head-to-wind) but leave the headsail cleated (ie don’t tack the headsail). Turn the boat so that you’re on a close reach (60 degrees off the wind) and let out the mainsail most of the way out so that it is luffing. Now wait until the rest of the boat’s headway speed bleeds off. That’s the key part. If you turn the rudder to windward (the wheel to windward or the tiller to leeward) before the speed bleeds off, the momentum of the boat may carry it through another tack. Once the speed has bled off, turn the rudder all the way to windward (wheel to windward or tiller to leeward) and lock it in that position (lashing the tiller).
Heaving to in a Storm
It’s really important to realize that this is a completely wise thing to do in a storm. With a huge caveat, make sure you have plenty of sea-room distance to leeward on the track of your hove-to reckoning, avoiding shoals, or the other hard stuff (like land!). Heaving-to in a storm gives you and your crew a rest from the elements. And it can be a safer means of riding out a storm rather than trying to sail it out. The boat is in a completely stable position. You should probably lower or deeply reef the main or raise a storm trisail (very small mainsail) as well as a small headsail to reduce loads on the rig. Here’s the kicker that is really cool – since the boat will be slipping sideways, a wake is left to windward. Any breaking waves hit this “slick” and flatten out, thus reducing the wave action on your vessel. Now that’s really cool.
Heaving To in a Sailboat in a Storm
Using Heaving to in a Man Overboard Situation
Heaving to can be a very effective crew over-board recovery technique. The very moment the victim goes over the side you can crash tack the boat and go into a heave-to position. You must be sure that the victim is able to swim, that they did not sustain injury whist falling. It’s your call on this one but it’s a technique not often taught and so isn’t considered in the panic but, it will keep you from getting too far away from your friend in the water which is clearly the biggest danger. Me? I’d still get the engines on. On that topic, the biggest danger they say from turning on the engines is not chopping your friend up, you’re smart enough not to do that, it’s from getting a line wrapped around the prop in all the panic. So just make that’s part of your “engines-on” routine in crew over-board practice. Next time you’re out practice man (or woman) over board.
There you have it, you’re now a heave to expert. NOT! You haven’t practiced it enough yet! And while you’re out there practicing it, have fun. Or should it be the other way around???
Start with the NauticEd Skipper Sailing Course now!
Posted by admin on July 26, 2011 under Bareboat Charter, Crew, Skipper |
Captaining a bareboat yacht on a sailing vacation is an acquired skill.
All of a sudden you’re transformed from friend, co-worker, family and sometimes complete stranger into the authoritative figure with ultimate power. That’s not an easy formula so I’ve put together the top ten tips on how to be a great captain.
When people are led by good captains they do not even remember that they were lead. That means they just remember that the vacation went off with out a hitch and the boat seemed to work itself, yet somehow, every one contributed and a great time was had by all.
Good leaders make people feel comfortable in any environment. Your confidence and promotion of a good time for everyone will help people feel comfortable through out the trip.
Obviously as every one will tell you, your job #1 is to ensure the safety of the ship and crew, however following closely behind that comes the job to ensure that every one onboard is feeling comfortable with you and the vessel. So let me shout this out load and clear. NO SHOUTING OR YELLING. The bareboat charter sailing vacation is not time to prove how much you know or to be Captain Blye. It’s time to prove your quiet confidence and steady character amonst your friends and family. After all I’m sure you’ll want them to come back with you and one wrong snarl and you’re off the christmas card list.
- Give up the helm time to others when practical and safe.
- Don’t be the supreme commander, you can do that with a rubber ducky in the bathtub at home by your self.
- Involve everyone in the sailing process (if they want)
- Don’t always be teaching and preaching but offer to show, help, teach.
- You’re not their to impress everyone that you can sail, instead impress people with these leadership skills instead. You’ll be liked better.
- Make the dinners and do the dishes more than every one else.
- Let others participate in the navigating.
- There is no need to stay on schedule. If the others are having fun shopping in a cute little port or laying on the beach let them stay. It’s their vacation.
- Read up on the local area with a travel book like Frommers and discuss the area and highlights of things to do with everyone.
- Plan the trip so there is only 3-4 hours of sailing everyday. And plan to stay in a port or two for a full day.
- Keep the boat tidy and clean. Every morning do a wash down of the boat, start the process yourself and I bet others will just join in. After a few days they will self start the wash down.
- Every day, give yourself a reality check and ask yourself this: “Am I doing all these things above?”
Ok that was 12 but the extra two were worth it 
. I didn’t make this stuff up though. The theory of it came mostly from a book I read called Lincoln on Leadership. His phylosophy was to always roll up the sleeves and get into the trenches. People follow more what you do rather than say especially when you’re in a new leadership role.
I’ve applied this phylosophy on the dozens or charter trips I’ve lead all over the world and I can assure you that if you pour the drinks, cook breakfasts and dinners, swab the decks, speak calmly and confidently, tell the jokes, go ashore to buy supplies before everyone gets up, give up the helm, be knowledgeable about the area and make good suggestions and just relax on the schedule, then everyone will remember you as being the BEST CAPTAIN EVER.
The top ten (12) tips on great captaining was extracted from the NauticEd Bareboat Charter Sailing Clinic which is packed full of real practical bareboat chartering tips guaranteed to enrich your charter sailing vacation and make you look like a star and it’s a requirement for your Bareboat Charter Master Sailing Certification. Take the Bareboat Charter Sailing Class online. And now available in a downloadable PDF. Did we mention our money back guarantee?
Bareboat Charter Sailing Course
Go to http://www.nauticed.org/sailingcourses/view/bareboat-charter
Have fun promote fun
The Grinch in Iles des Saints (actually just me having a lot of fun with a Christmas surprise for the crew)
Posted by admin on July 8, 2011 under Bareboat Charter, Crew, Maneuvering Under Power, Skipper |
The information contained in this explanation of what is propeller walk comes directly from the NauticEd Maneuvering and docking a sailboat under power sailing course which forms part of the requirement for the NauticEd Sailing Certification rank of Skipper.
You’ve learned to sail, sailed for a few years, and now you’ve upgraded to a bigger boat with an inboard engine. How frustrating! You want your new sailboat to go backwards but you keep going sideways. Welcome to propwalk. GRRRRR. This is not something that you probably got taught at your local sailing school because you learned on a smaller boat with maybe an outboard. Now you’ve got a much bigger and heavier boat and there are more expensive mistakes that can be made. Propwalk can be frustrating or you can understand it and use it to your advantage.
Let’s Understand Propwalk.
Imagine you’re walking up a spiral staircase. Each step is the same height and requires the same amount of energy to go up the next step.
Spiral stair case
Now imagine if the spiral stair case was tilted over 20 degrees. You’d find that as you went around the stairs they would be steeper on one side and flatter on the other. Or the stepper side cuts through more vertical space than the flatter side.
Stair case tilted
As we look at a propeller and the water flowing through it, the arc that the tips of the propeller follow relative to the moving water pushed by the propeller is a spiral shape, much like a spiral staircase.
Propeller Spiral
Or another way to see it, is to observe the sweep of each blade as it passes through the water.
Propeller moving water through the water
Now if we tilt the shaft of the propeller down, the spiral also tilts down.
Tilted Propeller Shaft
But we have to put put a few prefaces on this. There must be no boat hull above to affect the initial flow of water, the water must be deep and the propeller can not be moving horizontally through the water – that’s a lot of prefaces and not reality. But here is what that would look like anyway.
Propeller tilted down and moving forward
Now let’s put the propeller in close proximity to the hull of the boat where the water tends to move horizontally. This is represented here by the imaginary sweep lines. Here then you can see that the up swinging reversing blade (green -starboard) cuts more of the flowing water similar to the tilting staircase example above.
Propeller tilted with water moving horizontal
In much the same way as the tilting staircase, the down sweeping blade cuts through less flowing water than the upsweeping blade. This creates more force on the up swinging side of the propeller than the down swinging side and thus a torque is produced on the prop shaft.
This results in the following forces and thus a resultant clockwise torque on the boat.
Resultant torque on propeller
In a similar fashion, imagine yourself treading water in a swimming pool and your right arm swings in big circles while your left swings in smaller circles. Your body would move backwards but the action would also turn your face to the right and consequently your back to the left. The boat turns in exactly the same way.
In forward gear, the exact same phenomenon occurs, just in the opposite direction. However, we notice it much less because the water from the propeller is being pushed over the rudder which creates far greater forces and thus counteracts any tilt induced torque.
So in summary, a boat which has a counter rotating shaft, when in reverse, yaws clockwise (stern to the left) because the shaft is tilting downwards. Factors to reduce the effect include having a smaller diameter propeller or reducing the pitch (twist) of the blade or lengthening the shaft so that the water flow is further from the boat which would tend to allow the water flow to be more in line with the shaft. The effect is also reduced by a slower turning propeller IE less engine RPM.
An alternative way of mounting the propeller is called a saildrive and these are widely accepted in Europe. Saildrive systems have a horizontally mounted propeller shaft and therefore they do not create prop walk.
A sail drive unit does not experience prop walk
But there is no need to run out and go to the expense of converting your boat to a saildrive unit if you are experiencing frustration with prop walk. Because now that you understand the theory of propwalk, (more than 90% of sailors) all you have to do is practice the exercises in the NauticEd Maneuvering under power course a few times and you’ll have it licked.
So there you have it – now you’re 1 in a thousand sailors who understand how propwalk originates.
The NauticEd Maneuvering and docking a sailboat under Power sailing course shows students how to take advantage of propwalk. Just imagine you’re trapped in an EXTREMELY tight marina. Exercise number 8 wil show you how to get out. Turn the boat one way and you’re in trouble, turn it the other way and use a combination of wheel and throttle and you’re out of there with out a scratch.
Maneuvering and Docking a Sailboat Under Power Sailing Course
Take the NauticEd Maneuvering and docking a sailboat under Power sailing course now.
