Gybe Master Competition
Rules are easy.
to start new fun we could count how many times we did gybes , tacks or beach starts in half and hour and multiply it by total distance made at this time ( 30 minutes)

GM= Gybes x Distance (km)

For me yesterday it was

JP118L,8.0m2,fin 37.5

GM= 21 gybes x 8.62 km = 182.28

Whole idea of this matter is find an index that will appreciate your gybing or tacking skills.
Suggestion and modification are welcome as this is just first rough proposal.
BTW it is not intended to compete with alpha 500 but rather complement.


I think that calculations could be easy automated by computer if this index get some popularity.
For example programmer could count instead of gybes amounts of consequential vector direction changes with additional setup filters that min speed must reach ... 10 km or 15 km/h every time after turn to counts.
If feedback is positive we could ask nicely our great Dylan to calculate GM every time with KA72 records upload.

It would be an easy category to get a high score in but wouldn't be much fun to do so unless you are a freestyler.

Ok, I will bite.
Bored waiting for a skip bin to arrive.
Seems to favour lots of gybes/ tacks

Recent session 7.8 /120 /42fin 11x20.18 = 222
Historical session (with tacks) 6.3 / 90 / 32 21x19 = 399

and I could do my favorite course:





until it gets really really boring.

I'll humour you Macro....monday session 19gybes x 38km= 722

What's better??? a higher number or lower. maybe if you divide the number by time sailed then this could mean more??? i.e. my session was exactly an hour so 722/1hour equals 722.

Select to expand quote

FormulaNova said..
and I could do my favorite course:

until it gets really really boring.

Must have been Pre-kite days

Select to expand quote

sausage said..

I'll humour you Macro....monday session 19gybes x 38km= 722

What's better??? a higher number or lower. maybe if you divide the number by time sailed then this could mean more??? i.e. my session was exactly an hour so 722/1hour equals 722.

With all respect I think that is some mistake in calculations here.
We calculate GM for 30 minutes period (as 1 hour seems to be too long and for some becomes boring)

So if you did 38 km in 1 hour, then in 30 min 19 km
same with gybes - half of that - lets say 10 gybes in half an hour.

GM= 10 gybes x 19 km = 190

Select to expand quote

FormulaNova said..

and I could do my favorite course:





until it gets really really boring.

Looks promising for GM score but we need to know what the distance was in best 30 minutes and how many gybes.
I will not be surprised if you have higher score then me, as it looks like you have nice flat water here and I had half a meter chop. Still what counts is final score

How abut this:

GM = (Ave Speed over 30 min) x Number of Gybes

The higher the number the better the performance.

Also, rename it the Gybe Masochist

Select to expand quote

Milsy said..

i could go out in 5kts and do one thousand gypes over a couple km, the measure of that has no merit,

you are right, that is why distance counts over this 30 minutes, ( and later on even requirement to reach 15 knots max. on each leg once computer could be utilized to calculate GM. You still could do leg below 15 knots but then doesn't count ).
Now if you do even thousand gybes at 5 knots result will be very miserable.
Congratulation on this continuous gybing

BTW GM will not be incorporated in GPSTC, unless one day we all want it. For now the fun is just to compare performance and skills.

Milsy. If you post me link to this record in KA72 I may be able to help you calculate approx GM score, I could download gpx to my GPSResults and try to find good 30 min period.

Select to expand quote

John340 said..

How abut this:

GM = (Ave Speed over 30 min) x Number of Gybes

The higher the number the better the performance.

Hi John, That is exactly this same - distance = average speed over 30 min.

The higher the score that better! But as usual in racing smart tactics could help - down wind, shorter or longer runs ? flatter water etc.

What also counts that possibility for false positive result is very unlikely. ie somebody that can't gybe well and sail fast couldn't get good result here.

You are correct Macro, although the scale would be slightly different.

I still think Gybe Masochist is a better name.

Select to expand quote

John340 said..

You are correct Macro, although the scale would be slightly different.

I still think Gybe Masochist is a better name.

just 30 minutes of masochism not that much to ask

Too much to gain by doing lots of gybes at slow speed. Maybe try distance in 30 minutes times the log of the Gybes.

Select to expand quote

Paul Kelf said..

FormulaNova said..
and I could do my favorite course:

until it gets really really boring.

Must have been Pre-kite days

Nah, they are not too bad some times. Last year their numbers seemed down for some reason.

I think once they get used to you and figure out you are going to sail a normal course, you are okay. Of course there are those people that go 50 metres from the sand bar and turn around without looking, but I think you get to recognise their stance and learn to avoid them.

Select to expand quote

Ian K said..

Too much to gain by doing lots of gybes at slow speed. Maybe try distance in 30 minutes times the log of the Gybes.

Shouldn't be.
At slow speed distance will be very low.
Distance works like multiplier of your gybes.
Ideal will be this speed requirement 10 or even 15 knots max for each leg.
15 knots is quite good planing speed - so will be more adequate to cut off cheaters turning at low speed. But without computer program difficult to calculate.



This is graph representing speed. As we could see on every leg speed exceeded 20 knots at the point.
For our needs 15 knots should be adequate. 10 seems to be to low.

Didn't you try to devise something like this before Macro?

My answer is still the same.

We already have well proven and supported categories of 1 hour and Alpha 500m! that cover good Gybing and high average speeds

You can devise all sorts of other fun things to prove to yourself all sorts of esoteric things. But whats the point?

I think you're onto something Macro, combining the Alpha with the (half) hour.

But as a refinement on the idea, I think the comparisons will be better if it's the log of the gybes.

e.g Someone who can do 25 knot Alpha 500s back to back for half an hour will score....

25 knots = 12.86 m/sec, they do a distance of 12.86 X 1800 secs = 23.14 km

and do 23140/250 = 93 gybes.

log 93 = 1.968

score 1.968 X 23.14 = 45.55

Do the same calculations for 28 knot Alpha 1000s back to back for half an hour and the score is 44.4.

Comparable scores, both fantastic efforts.

The respective scores, if you multiply by the raw number of gybes, rather than the log of the gybes, are 2,152 and 1,347. Not really comparable scores for the respective efforts.

edit..

Had forgotten about proximity rules. Much easier! You only have to finish in proximity at the end of half an hour ( or thereabouts) So a few loose alphas in there don't matter, make it up at the end and always get a score.

Select to expand quote

sailquik said..

Didn't you try to devise something like this before Macro?

My answer is still the same.

We already have well proven and supported categories of 1 hour and Alpha 500m! that cover good Gybing and high average speeds

You can devise all sorts of other fun things to prove to yourself all sorts of esoteric things. But whats the point?

To be fair I created this index with people like you in mind.
I am sure that your score will be phenomenal and you quite right , this two alpha and one hour will be very relevant. This GM just almost combine this two skills in one.

So GM is not going to replace anything on GPSTC, just self test for willing to participate, even for their own knowledge or withing the mates group.
I could compare my results to similar beginner group and you could check against your advanced sailors ring.

Select to expand quote

Ian K said..

I think you're onto something Macro, combining the Alpha with the (half) hour.

But as a refinement on the idea, I think the comparisons will be better if it's the log of the gybes.

e.g Someone who can do 25 knot Alpha 500s back to back for half an hour will score....

25 knots = 12.86 m/sec, they do a distance of 12.86 X 1800 secs = 23.14 km

and do 23140/250 = 93 gybes.

log 93 = 1.968

score 1.968 X 23.14 = 45.55

Do the same calculations for 28 knot Alpha 1000s back to back for half an hour and the score is 44.4.

Comparable scores, both fantastic efforts.

The respective scores, if you multiply by the raw number of gybes, rather than the log of the gybes, are 2,152 and 1,347. Not really comparable scores for the respective efforts.

That is matter of strategy then. If you are able to perform alpha 28 then in same time should do more gybes in the same time and cover much bigger distance. Forget then about 100's of 28 alphas 500m in the row but adjust the distance to get maximum score. Additionally you are not limited to 50 m entry, as going down wind will be more efficient. That could be a bit unfair but life is not fair anyway and some have always better place to sail then others.
BTW I was thinking about the same thing. What is potentially maximum practical limit for GM value?

Just checking your calculation Ian

1 knot - 0.514 m/s

For alpha 25 knots =12.85 m/s
GM= 93 gybes x 23.14 km = score is 2152 - correct

for alpha 28 = 14.39 m/s

GM= 103 gybes x 25.90 km = 2667


Assuming that somebody is able to perform one after another alphas 500m at 25 knots and 28 knots for whole 30 minutes in row that will be maximum, theoretical humanly possible results for GM.

OK mate. I still don't get it, especially after Ian's post , but no harm I guess if it floats your boat.

One of my 1 hr's: 43.9km x 49 gybes = 2151

What does this prove again

I must admit though that doing one hours is sometimes a bit frustrating when you are at the mercy of the weather. How many times has one done a blistering 30-45 mins only to have the wind suddenly disappear

Select to expand quote

sailquik said..

OK mate. I still don't get it, especially after Ian's post , but no harm I guess if it floats your boat.

One of my 1 hr's: 43.9km x 49 gybes = 2151

What does this prove again

ok because we calculate value GM for 30 minutes period not 60 minutes for simplicity we divide both by 2.

Distance 43.9 km /2 = 21.95 km
Gybes 49 / 2 = 25

GM = 25 gybes x 21.95 km = 548.75

This is fantastic results and if anybody doubt it try to beat it

To add value to this Sailquick achivement I could also say that result is completely unintended for this competition
- which means that you Sailquick are able to do even much better if tuning strategy to this specifically GM .
For example if you just sail 30 minutes to save energy and don't need to worry about 50 m distance at all , just sail down wind.

Don't know about sailing down wind for 1/2 an hour Macro It'll take you 1.5 hrs to get back! I like the idea of 1/2 an hour, only tried the hour once or twice, it's too antisocial, can't stop for a chat. And I get lost in alphas, either too tight or too loose.

Out of interest, do the best Alphas always just kiss the proximity circle or does someone have something close to a pb that hit the centre of the circle?

Select to expand quote

Ian K said..

Don't know about sailing down wind for 1/2 an hour Macro It'll take you 1.5 hrs to get back! I like the idea of 1/2 an hour, only tried the hour once or twice, it's too antisocial, can't stop for a chat. And I get lost in alphas, either too tight or too loose.

Out of interest, do the best Alphas always just kiss the proximity circle or does someone have something close to a pb that hit the centre of the circle?

I don't mean down the wind completely but not limited to 50 meters entry and exit distance. So just matter of convenience how much down wind at each gybe, and matter of space available.
Beside 250 meters leg may not be optimum. More test needs to be done what is optimal length at specific speed.

The best Alphas usually just get in by a meter or two. Going back upwind the return is slower, especially when accelerating out of the turn.

It is interesting that Mal Wright hit it pretty much spot in with the proximity circle @ 50m. I think it was a bit of an educated guess on his part but turned out to be about ideal!

GM Results

548.75 -Sailquick
399.00 -Lao Shi
190.00 -Sausage
182.65 -Macro

Copy that and add your result somewhere in the middle , or even below Macro*
*then replace Macro with your name

Ha, ha! Gybing every 250m for half and hour would be exhausting!

Select to expand quote

Macroscien said..


I don't mean down the wind completely but not limited to 50 meters entry and exit distance. So just matter of convenience how much down wind at each gybe, and matter of space available.
Beside 250 meters leg may not be optimum. More test needs to be done what is optimal length at specific speed.

The optimal length will depend on the loading you place on the number of gybes. I suspect that using raw gybe no.s would favour very short lengths. The log of gybes was just my guess at getting a broad flat optimum curve which would put strategy in the game. It might be that the square or cube root of gybes works better or some other fractional power. Maybe a log to a base other than 10 would do the trick. You'd have to look at hour and Alpha data from GPSTC, work out the effect of gybing on average speeds rank the best efforts and then work backwards to get the "handicap" function.

Select to expand quote

Ian K said..
Had forgotten about proximity rules. Much easier! You only have to finish in proximity at the end of half an hour ( or thereabouts) So a few loose alphas in there don't matter, make it up at the end and always get a score.

agree , maybe we should consider the same rules for GM - the first and last leg must be within this 50 meters.
In the meantime we could sail at wish up and down the wind, but to finish we need meet this entry point by 50 meters.

PS. Now just for pure scientific purpose you could post your historical GM Ian.

You guys make my head hurt.

Peter - Maybe head up to Viccy Point or Wello with Kurt and George and joint some of us MBM for some longer runs than Shearwater. Then you can compare apples with apples without another category as suggested above. I've been out at Shearwater Ave many a time and it's not the place for results on the GPSTC BUT it's a fun place to windsurf and can be lumpy beyond imagination. It's a great training ground so head north and put those skills to practice with the other members of GC Speed Team and some of the MBM (and Board Crazy Guys). You have great enthusiasm for the sport.

Also did I mention I just like to go out and have a windsurf when it's windy!

Cheers
Marty

Select to expand quote

MartinF2 said..

You guys make my head hurt.

Peter - Maybe head up to Viccy Point or Wello with Kurt and George and joint some of us MBM for some longer runs than Shearwater. Then you can compare apples with apples without another category as suggested above. I've been out at Shearwater Ave many a time and it's not the place for results on the GPSTC BUT it's a fun place to windsurf and can be lumpy beyond imagination. It's a great training ground so head north and put those skills to practice with the other members of GC Speed Team and some of the MBM (and Board Crazy Guys). You have great enthusiasm for the sport.

Also did I mention I just like to go out and have a windsurf when it's windy!

Cheers
Marty

Well said Marty. That's what we're trying to tell him over the last 2 months. Peter needs to mix with another slalom guys, watch, ask and listen.