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FROM THE NAV STATION
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Ya-hoo!! We're finally finished with March -- Ya-hoo!!! I met a lot of new faces at the GLSS Safety Seminar last week. I even met a few folks who said that their traditional launch date is always Easter weekend. I'm jealous! It will be another month before I'm in the water. However, I'm still getting ready for the Mac Solo! Here's Step #11 in the countdown to the Mac Solo -- only 11 weeks away!
Step #11 - Study Your GPS Manual, Review Charts, Enter WP's
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Back in the olden days when Loran's were seen to be a frivolous luxury on a pleasure boat, dead reckoning was the mode of operation. Consequently, skippers knew their charts & plotting tools as a second language. We shared "tricks" to help us remember the important stuff like, "Can dead men vote twice?" That was the mnemonic to help us remember C-D-M-V-T or compass, deviation, magnetic, variation, true. If that still sounds Greek, that helped us translate from the actual compass reading at the helm to the true reading on the chart. And... All of this to give us our latitude and longitude within a half mile or so!
The electronic age entered yachting with the speed of a Great Lakes thunderstorm! The Loran entered the scene only to be replaced more quickly by the GPS. Today you can buy a GPS with electronic charts included for less money than you can buy a set of (paper) charts. At first glance the GPS is a piece-of-cake right out of the box! Connect two wires to the battery. Put up the antenna. And turn it on! Bingo - you've got your latitude and longitude to three decimal places and within 10-feet of accuracy! It's no wonder that dead reckoning has become a lost art!
Although dead reckoning was a lot of work for a rough estimation of position, the process gathered a ton of auxiliary information. For example, we jotted notes which read something like, "Expect 25-feet of water on this heading in about 90-minutes." This so-called auxiliary information warned us of upcoming shallow water as well as provided us with a confirmation of our dead-reckon position. A seasoned skipper would translate the bottom line of this entire process to: "If you know where you are, you can't run aground."
With a leap of faith, we could take that last statement and assume that we will never run aground since we have a GPS onboard to tell us exactly where we are to three decimal places! WRONG! I can remember hearing a VHF conversation between a skipper and the Coast Guard. He claimed that his GPS was giving bad readings, he was aground and needed assistance. The Coast Guard asked what the "bad readings" were on the GPS. I copied those reading and looked at the chart. His so-called "bad readings" put him in 2-feet of water surrounded by rocks. Chances are that he knew exactly where he was via the GPS, but had no idea where he was on the chart!
Take some time to read your GPS manual - from cover to cover. Read it like a textbook that you will be tested on. Plan to get 100% on your test. You can put your GPS to work for you, but you have to understand what it can do first. For example, assume that you will be tacking through Gray's Reef - why not set up a cross-track alarm that would automatically mark the safe boundary of your tacking limits? Enter various waypoints in your GPS all the way up the lake. Enter WP's for the things you want to avoid as well as WP's for your intended path. Enter a seemingly "innocent" un-lit can. During the night (or in fog) a quick verification with your GPS can tell you that this can is a quarter-mile to starboard - or a quarter-mile dead ahead! Put a notation on your chart for the points that you have transferred into the GPS.
Even if you work hard to load all possible Mac-Solo waypoints into your GPS, I can guarantee you that you'll still be doing some "button pushing" sometime during the Challenge. However, you can work NOW to guarantee yourself that you won't have to read the GPS manual during the Mac-Solo! There's a wealth of information in your electronics. Plan to use this for your own safety!
One more loose end to wrap up... If the mnemonic "Can Dead Men Vote Twice?" is used to translate from the actual compass reading at the helm to the true reading on the chart, then it begs the answer to: "What is the mnemonic to go from the chart back to the helm?" We'll find out how many old salts we've got out there!!!
Respectfully,
Patrick Nugent