Examples and Pictures



Overlay of the performance window on your navigation app.


Control of SailingPD is with a series of buttons, fit for a touch screen. Filters, windows on/off, logging etc.


Sailing PD recognises wind changes, current changes etc. It will warn you accordingly. On your instruments if you want so.


SailingPD can send your own NMEA messages to instruments. In this example, a $VTG is sent to a RM Graphic. In the position of SOG you see the actual performance, in the position of COG is the best Downwind Angle for the actual TWS. The $VTG looks like this: $SPVTG,$bestangle,T,,M,$sogperf,N,,K,A



Here an example with OpenCPN. SailingPD sends a NMEA MTW message to OpenCPN with $sogperf in the data field. OpenCPN shows 96 , being the actual performance (and not almost boiling water)


SailingPD can send messages over wifi (with UDP) to handheld devices like phones and tablets. With a free UDP viewer you can see how the boat and crew are performing. R-HEAD is Real Header.



A B&G Zeus3, showing performance % in RPM field. SailingPD sends a NMEA183 to Signal K. There translation to Nmea2000 PGN takes place.


Wind Shift info on an ST60 Graphic.

V-HEAD stands for velocity header


SPD can create a deviation table for your electronic heading device. In the PDlog, HDG and COG are logged every second. Post-processing a log creates a deviation table that can be read by SPD and correct the HDG when sailing.


Also a correction for the errors of the log speed can be derived from a PD log and subsequently be used to correct the values from the water speed. X-axis is 0,5 kts steps. Separate corrections for SB and PT sailing.


SPD can also create an STW-correction table for 8 different heel angles (4 per bow).

Deviation for these same angles is also possible. Here an example of STW correction per angle. Obviously, a lot of heel only happens at high speed... This correction table was automatically created from a SPD-log with over 600.000 log entries. It took 20 seconds.


Leeway per bow and per TWA from a PDlog. A post processor is avalable.


Leeway per bow and per TWS from a PDlog



Sailing PD calculates your boat's speed against the polar with the target speeds. Performance including current or without it, performance against water speed from the log, performance into the wind. Every second.



Data from the PDLog after 24 hours of racing.

X-axis is TWAs. Left Y-axis is performance, right is degrees.

Target heel comes from measurement certificate. Note that actual heel is more than target with TWA < 100 and smaller than target when TWA is > 100.

Not enough meat on the rail upwind, and not enough sail going downwind....

Performance suffers more downwind.


TWA and Performance after 24 hours of racing. Data from the PDlog.

When the TWA gets to 100, Performance starts to drop (see arrow). Too much wind for spinaker, no asym, the genua suffers behind the main.


SPD on a W10 mini PC, feeding its data to a Raspberry Pi. Signal K on the Pi converts the SPD-data into NMEA2000 and adds labels. The result goes via N2K to a B&G display, showing Performance %, Optimum TWA for the TWS and VMG Performance.