How to Navigate in a Fog
Objects may seem larger than they appear...
When operating in fog be aware that visibility can drop drastically. When visibility is between 30 and 150 yards objects, including other boats, may appear twice as large as normal. The illusion also tends to make you think that they are approaching at a much faster rate than they actually are.
Steering a straight line without a compass...
Many a small recreational boat owner will find themselves steering in fog without a compass. With no compass and with no reference points because of limited visibility, even the best helmsman will tend to steer in circles.
To steer a straight course, attach a light line high on the bow or from the mast and drag a drogue, cushion, or anything that can create resistance over the stern. Keep the line centered where it passes over the stern and you will steer a straight line.
Actions to take in fog...
If you see a fog bank approaching or fog starting to form be sure to fix your position by any and all means necessary, including electronically or by bearings. If possible, anchor and wait out the fog in an area which is too shallow to allow large ships in. Don't forget to ring your bell for 5 seconds every minute while at anchor. Post as many lookouts as you have onboard and listen intently for the sounds of other vessels.
If you hear a vessel approaching, sound the optional one short - one prolonged - one short blast to notify them of your presence.