A small diamond shaped navigational aid sitting atop a steel pole warns of “rocks” in letters so small even the use of binoculars can’t distinguish them. If you are close enough to read the message on the aid, you risk going aground.
Navigational aids are boaters’ road signs, much like signs on a highway, they direct you to safe passage. When accompanied by a chart of the area, they provide valuable information. Many boaters recognize cans, nuns and day beacons but others such as spherical red and white balls or diamond shaped aids can be confusing. If you do not understand the aids purpose or don’t have a chart to identify it, you could have a major problem.
The ability to read a chart overcomes the limitations of navigational equipment. A GPS, not equipped with a chart screen such as C charts, shows the direction to a position but the direction shown is “as the crow flies” (a straight line). It will not indicate shallows, reefs or even a land mass between two points.
Charts show red and green navigational aids; they indicate water depth, note rocky (rky) areas and wrecks, boulders (bLd) and shoals. The charts show Lighthouses and lighted aids; you can decipher one from another (G”l”FLG 45).
Boats with depth sounder transducers mounted astern should not rely solely on the sounders reading. Shoal areas, with quick depth changes, could place you hard aground by the bow while still showing good water depth astern. The use of a chart can show you where the shoals are and give you time to change course.
The ability to navigate by a chart is invaluable. Area Charts are the most reliable; most have “blow-ups” displaying local rivers and ports– an advantage when cruising somewhere unfamiliar.
To learn about charting, look for the latest edition of Chapman’s Piloting, or check out the Power Squadron or Coast Guard Auxiliary classes.
Conditions change constantly – keeping your navigational skills and knowledge updated for the water you are in is mandatory for all of our safety. You repeata this message often – thanks for the reminder!!
You forgot to mention that a chart can be completely out of date. You should never rely on any chart (electronic or paper) without updating it with the latest USCG Local Notice to Mariners available weekly via email. The prudent mariner will also consult cruising sites like Cruiser’s Net or Active Captain to take advantage of local knowledge and hazards confronting fellow boaters.
Great point Robert. Thanks for the input. Randy