gps-icesailing

Dear friends,

just a quick question to understand Alpha racing . I have to look for @1Km in GPS Results for the right analysis.

In the base rules it is not so clear for me.So i have to go 500m in , gybe and 500 m out ?

Cause when i look into @500 there are different results to my uploaded results.

When i take a look at @1km its the same in gpsresults and in the uploaded session.

Thanks for reply

Michael

standard Alpha Racing is the @500m, which is a distance over 500m with the start and end point within a distance of 50m. In fact this mean you sail 500m as fast as you can include a gybe and tryining to reach your entry point within 50m. 

For the Gyro GPS device I use 250m > gybe > 250m, total of 500m.

Distance between the start and end point 50m.

My display is +- 0.01km/h compared with GPSResults.

Alpha 500 its called (cause youre jibing point is at 500m) , total distance yes 1000m.

return point must within 50m

In my opinion the jibing point during an Alpha 500 is at 250m! (total distance is 500m)

With @500, the distance is max. 500 m (i.e. 500 m or less), with the jibe anywhere in the (max) 500 meter (which is usually somewhere around 250). See: https://www.seabreeze.com.au/forums/Windsurfing/Gps/What-is-an-Alpha?page=1

Thanks Harry for above link. It explains quite good, but I'm still wondering about the start and stop. I suppose since the alpha 500 is maximum 500 metres in total, then I can't start the alpha on an existing broad reach and end by going past that point (within 50 meters) and continue further at top speed? Correct me if I'm wrong. Do I have to stand completely still for a few seconds and then beachstart as fast as possible, sail approx 200-250 metres, gybe, sail back to the starting point 200-250 metres (within 50 metres) and hop off the board to make a complete stop as fast as possible from full speed (I know it sounds stupid, but the actual stopping can take a little time and slow the speed average). The rules for @500 doesn't say anything about how to start and stop so I feel kind of stupid... Maybe just going back and forth 250 meters in an 8 shape gybing like crazy without stopping will also create the alpha?

Thanks Harry for above link. It explains quite good, but I'm still wondering about the start and stop. I suppose since the alpha 500 is maximum 500 metres in total, then I can't start the alpha on an existing broad reach and end by going past that point (within 50 meters) and continue further at top speed? Correct me if I'm wrong. Do I have to stand completely still for a few seconds and then beachstart as fast as possible, sail approx 200-250 metres, gybe, sail back to the starting point 200-250 metres (within 50 metres) and hop off the board to make a complete stop as fast as possible from full speed (I know it sounds stupid, but the actual stopping can take a little time and slow the speed average). The rules for @500 doesn't say anything about how to start and stop so I feel kind of stupid... Maybe just going back and forth 250 meters in an 8 shape gybing like crazy without stopping will also create the alpha?

Hi,

Some more background can be found here -> https://logiqx.github.io/gps-wizard/alpha-racing/ 

Thanks a lot :-) Short answer for those in a hurry: Gybe like crazy without stopping (shortish runs in a small area). 

For a legal alfa 500 : 

  • Go as fast as possible half wind, for at least 225 m
  • Make a planing jibe with minimal height loss (max 50 m)
  • Go as fast as possible half wind back, for at least 250 m.
  • The average speed over the last 500 meter is then your alfa 500, if your exit is within 50 m of your entrance...
  • If your heigth loss is more then 50 m, the alfa is not legal, try again....

As the height loss is difficult to "guess", a reference is nice to have (sandbank, beach or whatever is parallel to half wind. Or mount a ESP-GPS to your boom, and get life feedback of your height loss while doing the alfa....

 

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