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Apps for Sailors: Smartphone AIS

by Donald McLennan, Posted October 11, 2012

While Automatic Identification Systems (AIS) have been appearing on more commercial and recreational vessels, many sailors still find it to be cost-prohibitive. As an alternative, I recently used a combination of smartphone apps and AIS websites...

Curse of the Cursor

by Peter Nielsen, Posted September 18, 2012

The first time I ever used a GPS on an offshore passage we almost lost the boat. The navigator, delighted with his new toy, had plotted a waypoint just off our destination, but somehow missed the long, low, unlit headland between us and it.

Digital Tracking Systems

by Ralph Naranjo, Posted June 13, 2012

Some might say that seamanship has been sidelined by technology, with safety and security more dependent on button pushing than sail changing. There may be some truth to this. But at the same time, there’s no question that today’s technology does fill some very real needs.

Nav Tip: Dead Reckoning

by Tom Cunliffe, Posted April 9, 2012

There aren’t many sinking sensations to compare with the one you get when your GPS decides to take an unscheduled break, especially if you’ve been relying on an electronic chartplotter. One minute you know exactly where you are. The next you’re surrounded by a trackless sea, feeling distinctly insecure.

Judging Leeway

by Tom Cunliffe, Posted March 14, 2012

Any boat under way in a crosswind, whether it’s a rowboat crossing a lake or a powerful cruiser reaching along the coast, will be pushed sideways to some extent. The effect is called “leeway,” and even big ships are subject to it. Sometimes leeway is insignificant; often it is not.

Do You Know Your Racing Flags?

by Sail Staff, Posted March 1, 2012

Everyone knows the Answering Pennant (AP or “Cat in the Hat” flag) means racing has been postponed and that the “P” flag means a standard starting sequence. But what about the “M” flag, an “N” flag over an “A” flag, or an answering pennant flying above Pennant 2?

Sailing in fog, inshore piloting, and more

by Tom Cunliffe, Posted July 1, 2005

This month: coping with fog, inshore pilotingSeamanshipSailing in fogSummer sailing and fog seem to be inextricably linked in some parts of the country, and everyone who races or cruises will run into a bank of the gray stuff at one time or another. When you do, your priorities change from making good time toward your destination to not running into other

Cruising Tips - Navigation

by Sail Staff, Posted May 2, 2006

Chart Smart (July 2006)We arrived off Suva, the capital of Fiji, after a 10-day passage from New Zealand. While we knew the island of Viti Levu was about 5 miles off our bow, we couldn’t see it because of a heavy rainstorm. My husband, Bob, turned on the computer and looked at the electronic charts we had added to our navigation suite a few weeks earlier. We wanted to use them to

Cruising Tips - Visibility

by Sail Staff, Posted March 27, 2006

Signal Advantage (March 2006)If you have an on-the-water emergency during the day, keep in mind that a mirror is a very effective signaling device. If the weather is clear and there is sunlight, the reflection from a mirror can be seen up to 100 miles away. While it does need sun, a mirror doesn’t depend on batteries, satellites, or the electronic watchkeeping of a potential

Chartplotter Protocols

by Steve Henkind, Posted November 20, 2008

Chartplotters are powerful extensions of GPS technology and provide tremendous convenience, but they can get you into trouble if you’re not careful. While my focus is on vector-based plotters (digitized charts, which are the ones typically found on recreational sailboats), most of my observations also apply to raster-based (scanned charts) plotters.Scale change matters.