Connor.kainalu
Member
How do you gauge performance gains with only one boat? Is there any tech that can measure minute speed differences and heading changes? I'm posting this on this forum because I plan to work in a development class (I14).
Performance gains without two boat testing
- Thread starter Connor.kainalu
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Skaf
Member
Most common tool in the fleet for this kind of thing is a Velocitek Prostart as it handles SOG, COG, and has some handy start-line functions on top. But I think most 14ers will tell you the best way to make speed improvements is to get ahold of a solid boat and spend time on the water practicing boat handling technique...
F18 Sailor
Super Anarchist
+1 to Skaf. I also find it hard to measure performance gains solo once you are past the initial performance curve in really any boat.
Daniel Holman
Anarchist
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Yeah time on water in a rigorous fashion focusing on going round corners, going through modes and gears whilst under pressure will make you better at sailing and yield decent results as long as your tactics are sound.
I'll be honest for assessing developmental gains, apart from trusting your backside (ie seat of the pants feel) I think that apart from a very serious multi channel acquisition syTem and post processing capability, everything else is pretty dodgy at best.
Its very easy to get another half knot letting some vang off, which won't be easy to associate with a couple degrees less height unless you have some very clever measuring stuff.
Thinking laterally do you know anyone local with a 49er to line up with? Or a fastsh beach cat? A 14 should do a hobie 16 upwind but an f18 would probs do the 14. Maybe something in between.
I'll be honest for assessing developmental gains, apart from trusting your backside (ie seat of the pants feel) I think that apart from a very serious multi channel acquisition syTem and post processing capability, everything else is pretty dodgy at best.
Its very easy to get another half knot letting some vang off, which won't be easy to associate with a couple degrees less height unless you have some very clever measuring stuff.
Thinking laterally do you know anyone local with a 49er to line up with? Or a fastsh beach cat? A 14 should do a hobie 16 upwind but an f18 would probs do the 14. Maybe something in between.
F18 Sailor
Super Anarchist
There may be an F18 locally. Best bet would be a 505 which isn't fast enough I think but probably a better comparison than a lot of boats. There are some Supercats in that area (17, 19) that are faster than a Hobie 16 by a good bit but not as fast as a F18 (by an equally good bit), so that might be a valid comparison. I suspect the upwind tacking angles are rather drastically different.
Daniel Holman
Anarchist
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If you are using a 505 to tune up something is very wrong with your 14 sailing.
well sailed 14 tacks thru 50 deg ish give or take I don't think that's far off beach cat with dagger territory.
well sailed 14 tacks thru 50 deg ish give or take I don't think that's far off beach cat with dagger territory.
Skaf
Member
DH I assume you mean 50deg either side of the wind (so through 100deg), otherwise I am doing something very wrong!
F18 Sailor
Super Anarchist
What SOG numbers are you seeing in the I14 upwind and downwind? Angles on a beachcat vary with wave state but 100 deg isn't uncommon, sometimes less in flat water+breeze, sometimes more in chop. SOG numbers vary from 9-13 kts once you start flying a hull upwind on the F18. Reaching and downwind low 20's are good targets but high teens are pretty easy averages.
BWR
Anarchist
If you are coming to SD, and if you decide to get a 14, there are several local boats to line up against. Some very well sailed boats, some beginners, and several in between. Just have to get out on a boat and learn to sail it first. Don't get too caught up in all the development until you know you can get the boat around a course very efficiently. Then start worrying about 1 boat, 2 boat and several boat testing and advancements. There are already local boats setting themselves up in very similar fashion so as to minimize the differences in boats, foils, rigs, sails, etc. and then try to work together to go better as a group. Get in a boat and sail it!
Daniel Holman
Anarchist
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Sog upwind maybe nearly wind speed up to 10kts in flat water up max to 12 kts on a very good day in wind. Bit footy.
Less in waves.
Bit more than wind speed downwind but topping out at high teens on vmg angles.
biggest top speed instantaneous I've ever seen (by someone else) is 25kts.
Think a new one sailed well will just have the better of a well sailed 49er in sub 12 kts, above that 49er rm takes over.
Less in waves.
Bit more than wind speed downwind but topping out at high teens on vmg angles.
biggest top speed instantaneous I've ever seen (by someone else) is 25kts.
Think a new one sailed well will just have the better of a well sailed 49er in sub 12 kts, above that 49er rm takes over.
Team_GBR
Super Anarchist
Daniel is right about data acquisition and analysis for training on your own. You need a lot of data points to know what is making a difference. At least you need to be able to sync video and gps data and then to be able to analyse what you have recorded after the sailing. GPS tracking alone doesn't help, because you have no way of knowing what changes were made and when. The next challenge is collecting wind speed data.
When new to a class, just get out on the water. Unless you are some Olympic rock star, just time on the water will give you huge gains and your butt meter will be accurate enough. You might combine it with a Prostart but you need to be careful because you need to be sure you understand what is causing changes in measured SOG and COG. Another issue is accuracy. Put 2 Prostarts on a boat and the chances are they will show very slightly different numbers as the accuracy is + or - 0.2 knots.
The other challenge is understanding what you are aiming at. You cannot work in isolation. You need target numbers and if you read what Daniel says (below), you will see that having numbers from the top guys isn't really very helpful
To start with, get some setting numbers to use as a base. With these, go out sailing and become the best you can be. Practice going through the gears and practice turning corners. Then go sail against others. Find how you are going against them and then repeat the process. For 99% of people, development of new ideas is the last thing you want for a fairly long time. If you cannot get competitive with standard gear and settings, you probably aren't going to change that through development.
When new to a class, just get out on the water. Unless you are some Olympic rock star, just time on the water will give you huge gains and your butt meter will be accurate enough. You might combine it with a Prostart but you need to be careful because you need to be sure you understand what is causing changes in measured SOG and COG. Another issue is accuracy. Put 2 Prostarts on a boat and the chances are they will show very slightly different numbers as the accuracy is + or - 0.2 knots.
The other challenge is understanding what you are aiming at. You cannot work in isolation. You need target numbers and if you read what Daniel says (below), you will see that having numbers from the top guys isn't really very helpful
This is because speed vary so much with conditions, be it wind or sea state.
To start with, get some setting numbers to use as a base. With these, go out sailing and become the best you can be. Practice going through the gears and practice turning corners. Then go sail against others. Find how you are going against them and then repeat the process. For 99% of people, development of new ideas is the last thing you want for a fairly long time. If you cannot get competitive with standard gear and settings, you probably aren't going to change that through development.
While I agree in general that two devices may show different values, there's no confidence level associated with that ±0.2 kn, reasons why it occurs nor methodology for how it was determined (e.g. it might be from latency due to averaging over a period, or from atmospheric effects that are only partially accommodated, or based on the minimum number of satellites in range, or …). So just because the accuracy is quoted as "±0.2 kn" doesn't mean it doesn't usually show speed to a much greater accuracy (or much lower if some higher level of confidence is used).
GPS can measure speed extremely accurately where speed is determined directly from observations (which the ProStart claims to do in the manual). It wouldn't take much to evaluate accuracy compared to a second or third device.
Matt D
Super Anarchist
While I agree that there are no substitutes for sailing with other boats, sometimes that isn’t feasible, and you wind up training solo. On the I14 I sail, we pair a Tactic Microcompass, and Speedpuck for instantaneous feedback. Post post-sail analysis, I've occasionally synced GoPro footage with GPS data via RaceQs. I've been surprised at how useful the data has been for tuning (I had very low expectations).
I've found the greatest advantage of the video/GPS combo has been clarifying when high or low modes pay, quantifying the cost of various maneuvers, and subsequently prioritizing training objectives. (A dauntingly long list!)
I've found the greatest advantage of the video/GPS combo has been clarifying when high or low modes pay, quantifying the cost of various maneuvers, and subsequently prioritizing training objectives. (A dauntingly long list!)
Pewit
Member
+1 for RaceQs for analysis combined with an action camera - and you can mount a smartphone below deck (in a waterproof container/case) to do the tracking. Pair it with a Pebble watch for RaceQs live feed/remote control via Bluetooth or use a Garmin watch with GPS which can run RaceQs without the phone.
http://raceqs.com/smart-watch/
Skaf
Member
We've been using a Garmin Virb to get action footage with GPS speed & position. It also has a handy heel angle overlay, just in case I needed yet another reminder to keep the boat FLAT!!!!
