I've found that reading really old research is often more interesting than the cutting edge stuff. To see how ideas develop and in just a few minutes cover decades of development is really the essence of the information age. Here is just such a paper. Gatehouse suggest measuring true position by sighting known markers to triangulate your position which was considered unfeasible . Well a GPS is a whole lot easier, but wasn't around 1970.
Gleaned Points of Importance to ArduSkipper:
- where to put the speedometer - "the boundary layer beneath the hull of a typical racing yacht was nowhere more than 1 in. thick and was only about 1/2 in. thick at a position 5 ft. aft of the forefoot, the position finally chosen for the sensor [on a 24ft boat]."
- "The leeway angle, which is the angle between the yacht's fore-and-aft axis and the direction of motion through the water, reaches a maximum value when the yacht is close-hauled, this value varying between about 2° and about io°"
- Wind Vane Error - the error of measurement of wind direction due to sail deviation seldom exceeds 3 degrees and is independent of wind velocity.,, [other researchers], indicated that the error was about + 7 degrees.... [Moreover] The error is such as to make the apparent wind angle greater than it really is.
- Anemometer - The diameter of each cup is 1 in. and the length of its supporting arm is 1 1/2 in. Departures from linearity did not exceed 0.5 per cent within the speed range 2-60 knots.
When you have to make a choice of boat accessories and marine electronics it’s always better that you start with procuring those items that are vital to your boats safety and proper operation.
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