B&G H5000 Pilot Computer - Manual (Page 103)

| 103 Operating variables | H5000 Operation Manual
VMG performance
VMG Performance shows the current VMG as a percentage of the VMG derived from the polar
table. The value is corrected for changes in wind speed.
Variable name (default)
Function name
VMG Performance (VMG Perf )
TACKING
Units %
Alarms N/A
Calibration N/A
Damping N/A
1
0
2
4
6
8
2
4
6
8
2
3
4
5
6
7
Polar Performance Curve
No. Description
1 Boat speed Kts
2 Optimum True Wind Angle upwind
3 Optimum True Wind Angle downwind
4 Target boat speed upwind
5 Maximum VMG upwind
6 Maximum VMG downwind
7 Target boat speed downwind
The Polar Table describes the performance of the boat in all conditions of True Wind Speed
and Angle. The Boat Speed is plotted radially against the True Wind Angle for each True Wind
Speed in turn. The result is a Polar Performance Curve shown above, this shows the boat
speed plotted for just one value of True Wind Speed.
Polar tables can be derived either by theoretical predictions, e.g. measurement certifi cates, or
by analysing the boat’s actual performance via software such as Deckman. The H5000 has one
polar table stored in its memory.