Originally Posted by jackdale
If you are using an integrated system, you may want to leave it in. The knotmeter, in conjunction with the GPS, can make set and and drift estimates. It can also be used with the wind instruments to make calculations for true wind angles and true wind speeds.
Yes, true. However, we don't have an integrated system. Even if we did, I'd still leave it out because around here the impeller would be completely fouled in about 3 days of non-use. Ours is centerline on the bottom of the hull -- it's either a dive down to clean it or swapping out the blank with the attendant geyser, every time we use the boat. Just too much hassle for a very marginal increase in data.
Remember, while bottom growth is about as fast as anywhere here on the Chesapeake, tidal currents are thankfully negligible in most places. Yes, there's a correlation.