Monday, September 16, 2019

Rules and Accidents

Windsurfing accidents happen. All windsurfers loose control from time to time, and on a crowded day, this can lead to people crashing into each other. Most of the time, it's no big deal. The windsurfer  who messed up knows it, apologizes, and (hopefully) offers to pay for any damages.

But every now and then, the outcome is different. This post analyzes one such incident that happened at the beginning of August at Kalmus. We will look at the accident based on statements the two involved windsurfers made; an eye witness report; and GPS tracks from one of the windsurfers that show exactly where the accident happened. The accident will be analyzed using the "U.S. Inland Navigation Rules" and the "International Regulations for Preventing Collisions at Sea" (Colregs), which govern all boating traffic in the US, as they are described on the US Coast Guard website.

The Parties

Sailor 1 ("CM") has been a regular windsurfer at Kalmus for more than 2 decades. He loves to sail fast, and used only slalom gear until last year, when he switched to fast freeride gear. CM is the singer in a wedding band.

Sailor 2 ("GG") also likes to sail fast, but can most often be seen on raceboards. He is a regular participant at the raceboard world and national championships, and has won races several times at the East Coast Windsurfing Festival Cape Cod. In the past, he had trained with the Spanish olympic team, and trained the olympic youth division in Spain. GG is a professor at Harvard.

The eye witness ("PF")  is a regular sailor at Kalmus who happened to be at the beach at the time of the incident.

The analyst - that's me. I have been windsurfing for 40 years. I originally learned windsurfing at the University of Konstanz in Germany. The 3-day course included a final written exam where knowledge of the "right-of-way rules" was required to earn the "VDWS Grundschein", a certificate needed to rent windsurfing equipment. I am a US Sailing certified Windsurfing Instructor, and  Instructor Trainer/Examiner with the Windsurfer Instructor and Programs Association (WIPA). I have participated in a number of windsurfing races, including the 2018 US Windsurfing Nationals, and organized the East Coast Windsurfing Festival Cape Cod for a number of years, where I also had the race director role.

The Context

The accident happened at Kalmus on August 3, 2019 at 6:23 pm. Wind was from the SSW-SW at 20 mph, gusting to 25. Most windsurfers had stopped sailing by then, and were in the parking lot packing their gear or had left already. Earlier in the day, the parking lot had been completely full, and the beach packed, due to a soccer tournament.

The Accident

According to the eye witness, both windsurfers were sailing almost parallel to the beach towards the launch area. GG sailed downwind, CM sailed upwind. CM jibed at the last possible moment before the stone sea wall on the west end of the beach, and crashed into GG.

This description matches how GG described the accident. GG added that he was planning to go in after this run.

CM added that he had to jibe because of the stones in the water, and that he believed that he had the right of way because GG was on port.

After the Accident

GG noticed substantial damage to the board and approached CM, expecting an apology. Rather than getting an apology, he was told by CM in a raised voice that he had done a "dick move" by not jibing when CM expected him to jibe. When GG pointed out that he was the "stand by" boat in the given situation since he was the downwind sailor, CM started a shouting match from which GG walked away. In a second discussion later in the parking lot where GG explained which navigation rules applied in the situation, CM disagreed and suggested that they should "agree to disagree". CM refused to pay for the repair of GG's damaged board.

The Damage

GG's windsurf board sustained significant damage in the accident, as shown in the following picture:

The damage went from the top to the bottom of the board, went through both the laminate and the sandwich layer, and included breaking the styrofoam core. Cape Cod Windsurfing offered to repair the board for $150. The board was in excellent shape before the accident, and even a professional repair would lower the resale value of the board by several hundred dollars.

GPS Tracks

GG used a GPS to record his windsurfing sessions, and submitted his GPS data for analysis. Here is a picture of his tracks for the day (click on the image to see a larger version):
Zooming in on the last run and the accident shows that the accident happened close to shore:
The yellow line in the image above is 100 feet long. Typical jibe diameters are between 150 and 200 feet, so it is clear that GG did not have sufficient room to jibe. This confirms his statement that he was on his planned last run of the day. The first GPS picture shows that he was planning to exit the water at the same place where he had launched and exited before. He was in the process of slowing down to stop, and his speed had dropped from 23 knots to about 18 knots when CM hit him.


The two windsurfers involved in the accident propose two different theories about who was at fault. 

1. CM states he was on starboard, and GG was on port. The windsurfer on port would be the "give way" vessel and would have to change course to avoid a collision.

2. GG states that CM was upwind before the collision, and therefore the "give way" vessel. Furthermore, CM was in the middle of a jibe, and a sailboat or windsurfer does not have right of way during a maneuver.

A further uncertainty arises from the question whether CM was overtaking GG. CM generally tries to sail as fast as possible, and typically uses larger sails than other windsurfers; the often passes other windsurfers on the water. Since GG was slowing down to stop, it is quite possible that CM passed GG before jibing.

Assuming that CM passed GG before jibing, the rules that apply are defined in rule 13 of the "Amalgamated International & U.S. Inland Navigation Rules": "any vessel overtaking any other shall keep out of the way of the vessel being overtaken." The overtaking boat has the"duty of keeping clear of the overtaken vessel until she is finally past and clear". This means the overtaking windsurfer may not just pass another windsurfer, and then immediately change course or speed to a collision course. The conclusion is:
If CM passed GG on the way in, he did not meet his obligation of "keeping clear", and was at fault at the accident.

Since we cannot know for certain if CM passed GG before jibing, we must also look at the incident assuming that he did not pass him first. Common sense tells us you can't just jibe from an upwind position to get starboard rights just before you crash into someone - the other person would not even have time to react to avoid the collision! But is there something in the rules that we applies?
The first rule that does apply is Rule 6 - "Safe Speed":
"Every vessel shall at all times proceed at a safe speed so that she can take proper and effective action to avoid collision and be stopped within a distance appropriate to the prevailing circumstances and conditions."
If one windsurfer sails in a straight line, and one windsurfer changes course, only the windsurfer changing course can actually know that the collision may happen, so it is his obligation to slow down or stop.
Furthermore, Rule 7 - "Risk of Collision" states:
"Every vessel shall use all available means appropriate to the prevailing circumstances and conditions to determine if risk of collision exists. If there is any doubt such risk shall be deemed to exist."
In clear text: if you jibe and are not sure that you will be clear of anyone else in the area, you must assume that you are creating a risk of collision. Rule 8 covers actions to avoid collision, and Rule 8 e again states:
If necessary to avoid collision or allow more time to assess the situation, a vessel shall slacken her speed or take all way off by stopping or reversing her means of propulsion."
Other parts of Rule 8 state:
"Action taken to avoid collision with another vessel shall be such as to result in passing at a safe distance " and
"Any action taken to avoid collision shall be taken in accordance with Rules 4-19 and shall if the circumstances of the case admit, be positive, made in ample time and with due regard to the observance of good seamanship"
From the rules above, we can deduct the general guideline that you do not have any right of way when you maneuver. Whenever you jibe or tack, it is 100% your responsibility to make sure you do not crash into someone.
The bottom line is simple: you cannot just jibe into someone! You either have to jibe so you pass them in a safe distance (which is at least a mast length), or do it so that they have "ample time" to see you and adjust their course. If that is not possible, you'll have to stop, if necessary. In a situation like here, of course, the accident could have easily been avoided if the upwind sailor (CM) had tacked instead of  jibed.

Why bother?

Some of my readers may wonder why I bother posting about this, especially since the incident happened more than a month ago. I am not naive enough to think that CM will read this post, follow the links to the rules, and then say "Oops, now I understand I was wrong", then apologize to GG and offer to pay for the repair. I would not expect this from someone who forces windsurfing women off their boards rather than showing some courtesy, and then yells at anyone trying to explain to him the right of way rules. 
However, a few other windsurfers I talked to stated they were not sure what the rules were in such a situation, and they may find the discussion and links above helpful.
The final straw, though, was CM's continued aggressive behavior. In the past month, he had shown often that he will jibe where and when he wants to, and if someone is in the way, that's their problem. At least once, he has been seen getting dangerously close to another windsurfer. Together with the fact that his jibes have become a lot worse, with much less control and a higher crash rate than in the past, he is a danger to other sailors. Perhaps this was always the case - others tell stories where he almost got beaten up by slalom sailors at Kanaha for jibing too close to their spouses. But with his deteriorating skills and complete lack of consideration for others, he is becoming more dangerous than he was. This particular accident, in the end, had a "lucky" ending, with only a board getting damaged. Just a foot to either side, and a person would have been hit, which likely would have resulted in broken bones.
He also seems more willing to insult and threaten people than perhaps learn from the incident. When he pulled into the Kalmus parking lot a couple of days ago and noticed that I was telling Andy Brandt about the incident, it would have been a great opportunity to check with Andy if his understanding of the situation was correct - who'd know better than Andy? But instead, he rolled up to where I was rigging, and started to insult me and my friends ("you can't sail and everyone you hang out with is a bad sailor" were his kindest words), and yell at me that this was none of my business. Well, he's wrong about that. If I see someone who sails dangerously enough to cause crashes with significant damage to other windsurfer's equipment, without any signs of regret or change, I certainly will not be quiet about it. Approaching me to intimidate and insult me to keep me quiet won't work, either.

Sunday, September 8, 2019

GPS Device Poll - Initial Results

Below are some initial results from the device poll. 86 people answered the questions in less than a day.

Saturday, September 7, 2019

GPS Team Challenge Device Poll

Regular readers of this blog may have discovered that I love the GPS Team Challenge.  One of the issues that comes up on a regular basis on the "GPS and Speed talk" forum is the question about which GPS devices are allowed. On one hand, the competition aspect requires high accuracy, which means expensive devices which often have drawback; one the other hand, there is a desire for inclusiveness and making it easier and cheaper for new members to join.

One option that has been discussed is to create a two-tier system where postings from just about any GPS device are allowed, but only postings from approved, highly accurate devices count for the competition, that is the monthly and individual rankings. The "other" speedsurfing site,, has a similar system in place for "normal" and "record" postings.

I have create a short poll to see what current and potential GPSTC members think about allowing such "two-tiered" postings. You can fill it out here. Below are screen shots:
Only the first 2 questions are required, the rest is optional. Here's the second section:

I'm planning on posting the poll results on this blog and on the Seabreeze forum .. if anyone bothers answering the questions! Here's the full address of the poll:

Tuesday, September 3, 2019

Squiggles and Half Straps

Yesterday was supposed to be good for foiling in the afternoon, with wind in the mid-teens. We waited for it. And waited. And waited some more. It was almost 5 pm before the meter readings picked up to 13. 45 minutes later, I was on the water at Kalmus. Nina decided not to join me after hearing about jellyfish on shore (a first for this year), and seeing rain showers coming in.

I had rigged the 6.5, which proved plenty big when the wind picked up to 16 mph averages. Since the tide was high, I was able to use the 90 cm mast, which is easier and more fun than the shorter masts. On the back of my zombie slalom board, I had mounted one of the Slingshot "half" footstraps, with the open end facing forward, to test it.

Here are the GPS tracks from the session:
It was a great session! Due to all the jellyfish talk, I skipped working on jibes and just tacked, with 11 of 14 tacks dry. I also crashed once in the middle of a run. The swell was quite big for the light wind, with some 2-foot rollers coming through from time to time. My Infinity 84 foil is quite sensitive to what happens in the water, and going almost parallel to the waves means that the flight height can change quite a bit going up or down a wave. So after a while, I gave up trying to foil in a straight line, and instead played with the swell. When going down a wave, the foil wanted to go drop down to the water; when going up the back of a wave, it wanted to rise up. Once I figured that out, compensating for it by moving the rig or my weight was a fun little exercise. The long mast definitely helped there! Breaches were virtually non-existent, and touch downs were gentle and brief. Drawing squiggly lines in non-breaking wind swell is so much fun!

I liked the half strap in the back. It is quite easy to slip into it sideways, and having the strap helps to have the foot in the right position, and perhaps a bit more control of the board. On the side without the strap, I found myself looking down a lot to see where exactly my foot was. I guess I'll put the second strap on the other side, but leave the front straps off for now.

I kept the session short since it looked like more rain was coming, and I did not want to make Nina wait too long. But doing a short foil session meant that I never reached the point where my attention starts to wander, and crashes slip in. We ended the day by celebrating the end of the tourist season at the British Beer Company. What a great start of September, my favorite windsurfing month of the year!

Sunday, September 1, 2019

Foil Setup: Front Wing Placement

Isn't it curious how sometimes things can be easy and confusing at the same time? Setting up equipment for windfoiling can be that way. The general rule is simple: "you want the front wing located as close to the center of your stance as possible", the Slingshot manual says. Sound easy, right? Let's look at a few examples, starting with Nina's foil setup:

This is her old Skate 90 freestyle board and the Slingshot Infinity 76 foil with a 60 cm mast, the gear she uses for foiling 90% of the time. She can foil on this in 12-13 mph wind with a 5.2 m freestyle sail, with very good control. She's also foiled through a few jibes, and started on duck jibes and 360s. Let's zoom in a bit:
I placed the ruler close to the middle of the front wing, where the "center of lift" (COL) is. If you compare it to the position of the foot straps, you can see that it is close to the middle, just a bit towards the back strap.

Now lets look at another setup that does not work nearly as well:
This is my Skate 110 with the Slingshot Infinity 84 front wing. It's shown with a 45 cm mast, but ignore the mast size for the time being. Here's a zoom-in:
You can see that the COL is much closer to the back strap. When I tried this setup (with a 71 cm mast), it was hard to get up on the foil, and felt very unbalanced once up. Nina tried it, too, and came to the same conclusion.

What's the difference? In both setups, the foil is mounted in the "C" position on the fuselage, which put the front wing closest to the front. However, my Infinity 84 wing is significantly larger than Nina's i76. All the extra area was added to the back of the foil, which moved the "center of lift" back by about an inch or two. In addition, Nina is using the Powerplate to move her foil forward even more:
You can see that the Powerplate here moves the mast forward by about 2 inches. In total, the COL for Nina's setup is about 3-4 inches further forward than for my setup!

So the obvious thing to try is to move the front wing for my setup further forward. I did this by drilling a new hole into the fuselage exactly 2 inches behind the rear hole for the "C" position. By using these two holes, I now have a "D" position where the front wing is moved forward two more inches:
You can see that the COL has moved forward to be closer to the middle of the foot straps. When I tried this setup, it worked a lot better. The foil came up a lot earlier, and it felt more balanced when up. But please note that the extra hole weakens the fuselage, and that the larger distance makes it more likely that the fuselage will bent! So I'm not recommending that you copy this approach!

When I replaced the powerbox in my Skate with a foil box, I put the foil box at the same position that the powerbox had been in. I actually had tried to use the Skate 110 for foiling before, and it had worked well enough - but I completely forgot that I had used the Powerplate, which moved the foil forward! In hind sight, I should have just added a couple of US fin boxes to the Skate 110 for use with the Slingshot pedestal mount. Adding the tracks so that they partially overlapped the powerbox would have been easier than using the foil box, and given me some adjustment room (in addition to the option to mount the mast in the A or B position). That would have made it easy to fine-tune everything for a perfectly balanced setup.

One thing that perhaps let to my confusion about the box placement is that the "C" position works very well with my slalom board:
I don't use foot straps on this board for foiling, so I placed booties where I usually put my feet. The back foot is usually all the way back against the strap that I use to attach a safety line to, and the front foot placement varies a bit depending on conditions and power. But it is easy to see that the distance between COL and back foot is more similar to Nina's setup than to my "unbalanced" setup shown in the second picture.

A closer look at the footstrap placement on the different boards reveals a significant difference: on the slalom board, the back strap positions are about 2 inches further back than on the freestyle board. That's true for the boards shown, but also for several other (newer) Fanatic slalom and freestyle boards in the garage. On some foil boards like the Slingshot Wizard, the back straps seem to be even further back, so that the back foot is where the mast is. Here's an image of the Slingshot Wizard 125 with the foot strap position highlighted:
For comparison, here's an image of a typical freeride board:
The back footstraps are several inches forward of the fin / foil box, similar to what we saw for the Fanatic Skates.

So, if you'd want to use a Slingshot Infinity 76 foil with a Wizard 125, the consensus is that the mast should be in "B" position on the fuselage. For use with a typical freeride board where the footstraps are further forward, the mast has to be in "C" position for the i76.

For the Slingshot Infinity 84 front wing used with a Wizard, the foil should be mounted in the "C" position. This means that use with a freeride board would require a "D" position! Since the fuselage does not have a "D" position, anyone trying such a setup will likely be disappointed (or has drill an extra hole).

Interestingly, Fanatic has chosen a more forward footstrap position for their foil freeride board, the Stingray:

There are lots of option to mount the rear straps, but all of them are pretty far forward. This makes sense, since Fanatic also sells several "foil ready" boards with similar strap positions. All these boards need to work well with the Fanatic foils. Compared to the Slingshot foils, the Fanatic foils have the front wing mounted further forward (the mast is further away from the front wing), which is necessary for a balanced setup.

If you buy a matching foil and foilboard from the same brand, this is not an issue, since you should be able to simply follow their setup instructions. But it you try to "mix and match" foils and boards, subtle differences like a 2-inch variation in the footstrap placement can make the difference between a setup that works beautifully and a setup that is barely useable. Similar issues arise from the position of the foil on the fuselage. For example, RRD freeride foils have the mast mounted close to the middle of the fuselage, while the Slingshot Infinity foils have the mast closer to the front wing, even in "C" position.

For board conversions, some of these problems should be avoidable by going the mast track/pedestal mount route, especially for Slingshot Infinity foils. Whatever option you choose, though, I suggest to check where the front wing will end up before you start the router!
I have contacted Slingshot with a suggestion to add a "D" position to the fuselage, and heard back from Wyatt Miller, their windsurfing guru. He said moving the mast further to the center increases the chances that the fuselage would bent, since it has more leverage. Nor does it help that the extra hole weakens the fuselage! Apparently, jumping with the larger front wings (Infinity 84 and 76) can bend the fuselage even in B or C position, so Slingshots suggests to use smaller front wings for jumping and things like loops. I had actually noticed a bit of new instability when using the "D" position, but the i84 is always sensitive to water movement caused by chop and swell, so it's hard to tell if this was caused by increasing the distance between wing and mast. To be on the safe side, I'll add a track mount to my Skate.

Tuesday, August 27, 2019

Jellyfish Time

August is jellyfish time. We had a foil session at Kalmus yesterday that was nice, except that we saw lots of jellyfish. Close to the Hyannis Port Harbor, I saw swarms with hundreds of individuals of the Altlantic Sea Nettle:
Sea nettle, Chrysaora quinquecirrha.
Picture by Jarek TuszyƄski / CC-BY-SA-3.0 & GDFL
It's a beautiful little beast, but it gets scary when you see lots of them so close together that they should worry about their tentacles getting all mixed up.

Sure enough, a little while later Nina had a close encounter of the painful kind with one of them. When her foil took a (rare) nose dive and she landed head-first in the water, a sea nettle was there to great her, wrapping itself all around her face and neck. I heard her scream from a few hundred meters away! By the time I got close to her, she was sailing to shore as quickly as she could, and then ran to the snack bar for some vinegar and baking soda treatment (life guards are not on duty during the week anymore, it seems).

When I got to shore, she was nowhere to be seen, but I had an idea what had happened, so I started carrying all our gear up from the beach. Nina was in quite a bit of pain until we got home, and she could take some pain killers and a very long, very hot shower. Hot water helps with the pain, and may denature some of the jellyfish toxin, so she felt a lot better afterwards.

A common "side effect" of sea nettle stings is congestion and sneezing, which was evident even after she took anti-histamines and a decongestant. But she slept through the night, and everything is good again this morning. Fortunately, the local jellyfish are usually more of an annoyance than a real danger - unless you are unlucky enough to have an allergic reaction. I also definitely would not want to fall in the middle of a swarm!

We had northeasterly wind yesterday for the third day in a row. On Saturday, we'd gone foiling in Barnstable Harbor, a very nice session that Nina called "the best foil session ever". She almost foiled through a duck jibe - nice! Sunday had been great, too, with a Duxbury Bay session and wind in the low twenties. I took the slalom gear out for the first time in a while - the Falcon 99 and Racing Blade 7.0 worked quite nicely to get some decent numbers for the monthly ranking in the GPS Team Challenge. I switched to freestyle gear when the tide dropped too low for runs along the entire bay, but got too cold to try anything when the sun went away. Still a great day.

As for jellyfish in Nantucket Sound, we should see a drop in numbers soon. Water temperatures have already dropped from 76 F to 72 F, which should help. However, the full moon at the end of this week may increase the number of jellyfish for another week or two. Also keep in mind that jellyfish are hard to seen on a typical choppy southwest day in Kalmus - when we go foiling on a northerly day where the water is flat and clear, we always see a lot more jellyfish. Right now, there's no way I'd windsurf in board shorts or a shorty!
After posting this to Facebook, someone pointed out that he had very good experience with anti-jellyfish sunscreen. I did not even know there was such a thing! But there are several scientific studies about the effectiveness of the "Safe Sea Sunscreen and Jellyfish Protective Lotion". On one study, the cream reduced jellyfish stings by more than 80%; in a second study,  the protective effect was even higher. We've ordered some!

Saturday, August 17, 2019

Foil Box Conversion

With the ABK camp in Hyannis coming up in 4 weeks, it was time to get my board ready. I have been foiling on my old Warp 71 slalom board without footstraps, but that just won't do when we start working on foiling 360s. So out with the powerbox, in with the foil box! 

We had used the Skate 110 a few times with the Powerplate to see if it would work (it did). When I put it up to start on the fin box replacement, I noticed that the Powerplate had damaged the underside of the board:
Where the front end of the Powerplate meets the board, the top carbon layer was broken.  No big deal to repair, but it sure was good I had ordered a foil box!

I studied a couple of videos from Alex Aguera to get an idea on how to do this. I ended up buying a router at Harbor Freight Tools, and used it to get the old powerbox out. Here's an image from the start of this process:
I had never used a router before, but it went well enough. Cool to learn how to play with new tools!

Fitting the new box was not hard. I hit the first surprise when I glued it in with epoxy and fairing filler: when turning my back for a minute, the box started to drop, and was half way through the board before I noticed! Luckily, I turned in time, pushed it back up, and added some support below to keep it from falling again. Here's the setup:
The masking tape on the sides is keeping the fin vertical to the board. After a bit of sanding next day, the box was ready to be glassed in:
I used a layer of carbon and two layers of 4 oz S-glass, topped by a layer of 2-oz glass, on the bottom:
This was the first time I used 2 oz glass on top. This stuff is great! It makes a much smoother surface, and does not distort when you squeegee the epoxy. 

Everything had gone well so far, so I pushed on. A few hours later, I glassed the top side: a layer of 4 oz glass, 5 smaller pieces in the middle, and another layer of 4 oz and 2 oz. I copied Alex' approach, and put all pieces on before putting the epoxy on top and massaging it in. Worked great, and another new thing learned. But then I saw that the glass in the middle was bulging outward .. not good! But a few more minutes with the squeegee, and the extra air was pushed out. I watched it for a while, and then let it sit for a few hours to polymerize.

When I got back, there was an unpleasant surprise: the bubble had reformed, and pulled the glass away from parts of the fin box. Apparently, glassing both sides of the box was a bad idea. A slight increase of the outside temperature made the air expand. Usually, I glass in the late afternoon, when temps are dropping, but today, I had clearly started too early.

Fixing the problem required drilling a few small holes, injecting epoxy, and then pushing the center of the glass down. The setup included some wire, three pieces of wood, and a 12-lb weight, but it did the trick. First, though, I put a few small holes in the bottom where the glass covered the fin box, so the air could escape!

The next step was removing the glass cover at the bottom with the router and a trim bit. That was really quick and easy - cool! All that remains to be done now is finishing work - sanding, drilling a couple of holes for the screws, hot coat, and paint. The board should be ready for foiling in a couple of days, which should mean that we get plenty of wind at the start of the week to keep me on the "slapper". There are worse fates!

Monday, August 12, 2019

Five Days and Counting

Kalmus windsurfers often told stories about how it used to get windy every afternoon. I used to think those stories suffered from the same effect that makes fish you caught get bigger with every retelling of the story - not anymore! It's been blowing in the 20s for 5 days straight, and two more days are in the forecast. Nina used her 4.0 twice, and was overpowered on 4.5 and 4.7 a couple of days.

It got crowded some days, but it was almost empty on the weekend. There seems to be a relation to the "Pro Forecast" on iWindsurf - the crowds come if it's high. But there seems to be very little relation to the actual wind. In all fairness, the same seems to be true when looking at the computer predictions - none of the computer models correctly predicted wind in the high twenties. Today's Pro Forecast is all red: 16-22 knots all afternoon long. My prediction: it will get crowded!

Saturday, July 20, 2019

Jibe Practice for Foiling

We got our second foil three days ago: a Slingshot Infinity 84. I've foiled on it only for two short sessions, but so far, I love it. It gets me flying as quickly as Nina on the Infinity 76, with a sail that's just one sail size bigger. But more importantly, it can handle all my extra pounds much better than the 76 - no more spinouts and breaches! But my first attempts at foiled jibes on the i84 looked quite similar to those on the i76 - mostly crashes, with an occasional exception where I plane out of the jibe after the board touches down.

As new foilers, we are in a stage where we often hope that the wind does not pick up beyond 15-18 mph. This summer so far, the wind often has played along, but not yesterday - it picked up to the high 20s, gusting to 30. So it was time to take the old slapper out for a change - my white Skate 110 that I had repaired for foiling, since I had forgotten to put my new Skate into the van. Off to Egg Island we went. Nina tried her usual freestyle moves, but I was on a foil related mission: practice the sail first jibe!

After more than 20 AKB camps, I am a step jiber - when the sail moves, the feet switch (or at least they should). But for foiling jibes, there's plenty of advice to do a sail-first jibe (also called Power Jibe and Speed Jibe): flip the sail first, and the feet later. That's what the Horue jibing tutorial suggests, and Balz Muller says the same thing. I have tried enough step jibes on the foil to see that separating the sail and foot movements might be a good idea, but I almost never do sail-first jibes .. which means I did not really want to try them when flying. But being nicely powered on a 5.0 on perfectly flat water at Egg Island - there's no better training grounds!

So after a few regular jibes and a 360 try or two, it was sail-first jibe practice. I was surprised to find me planing out of them after just a few tries, and having tons of fun! I'm not good at multi-tasking, so flipping the sail first while maintaining the carve, and then switching the feet, seemed more natural to me than doing two things at once. When the wind picked up after a while, I ended up doing tacks on one side so that I'd be able to do some "slow speed runs" along the sandbank on the way back. Since I tack the foil much more than I usually tack my shortboards, my tacks had improved a bit - nice!

Here's the GPS tracks from the "forbidden jibe" session in the "kiddie pool" at Egg Island:
The jibe analysis with GPS Action Replay showed that this was one of my top-15 best jibing sessions (from more than 1300 sessions). Cool!

Hopefully, the wind will remain lighter today, so that I'll get a chance to try foiling sail-first jibes. For anyone who wants to foil at Kalmus, check these tracks from my last foil session there:

I was using a relatively short (71 cm) mast, but still ran aground about 800 feet from shore at low tide (0.2 ft). I tried walking into deeper water several times, but always made ground contact again when I tried to foil away. You can see the stones pretty well on the Google Earth image. I would have probably been fine another 100 or 200 feet further out, but the ground there is uneven, and my head was barely above water in the deeper spots. I ended up just body-dragging in.
So if you foil at Kalmus, check the tides, and make sure to walk out far enough at low tide! Once the tide level goes beyond 1-1.5 ft, even a 90 cm mast should be fine, though.

Saturday, July 13, 2019

Foil pictures

We had another nice foil session 2 days ago, and Eddie took some nice pictures. Here's Nina on the foil and Gonzalo on a longboard:
Nina was on a 5.2, Gonzalo on a race sail (8.5 or 9.5). He was one of the few windsurfers who was planing consistently - most guys on 7 m sails had a few good runs, but mostly slogged.

Fortunately for me, Nina was a bit overpowered on the 5.2, so she came in after a short session and let me have a turn. I started out on the 6.5:
I never like this sail very much, largely because it is low-end oriented, while all my older Gaastra Matrix sails were top-end oriented. However, it was great for foiling, powerful but stable. Cool!

The picture above shows my favorite "flight height" on the 60 cm mast: just barely above the water, so that the board just touches the waves a bit every now and then. One excuse for flying low is that I frequently get spinouts when most of the foil is out of the water. Those are usually not very dramatic, but often end up with the board slapping back down onto the water. The gently touches when flying low are much nicer, and loose a lot less speed. But perhaps it's really just my inner chicken asserting itself.

We took turns on the foil a couple of times, and I used the 5.2 for my second session. Here's another "flying low" picture:

Occasionally, I ended up foiling a bit higher, and I'm definitely making progress controlling the height.
I'm still amazed how much fun foiling is even at low speeds. My speeds typically were around 10-13 knots, with only rare spikes above 15 knots. That's about half of the speed of sailing on freeride or slalom gear! Here are the tracks for the day:
I had a few runs of 700-800 meters, pretty much the entire distance I foiled (limited by shallows on the left, and the stones from the old pier on the right). The longest "high foil" without touching the water was probably less than half of that distance. I made a few dry jibes, one of them close to planing, but did not foil through any. In contrast, Nina foiled through one of her jibes "by accident". I'm sure she'll have more of these "accidental foiled jibes" soon.

We have ordered a second foil, and it should arrive early next week. Maybe that will cause the strong summer winds to come back? We stayed with Slingshot because we really like the modular system, and the short 60 cm masts are great for low tide foiling. But we decided to get an Infinity 84 as the second foil (together with last year's front wing which Slingshot pretty much gives away for free), since I hope that it will push my almost 200 pounds up sooner. It may be a bit slower, but I don't think that's a bad thing anymore!

I almost ended up buying a Starboard GT-R foil. It would have been a few hundred dollars cheaper, and comes with a longer fuselage, which should make keeping a constant height much easier. One of the speedsurfers we met in Western Australia, Stroppo, regularly posts sessions with top speeds in the mid-20 knot range from the Starboard GT foil. Without any doubt, I'd be at least 5 knots slower (just like on the windsurf board), but that would still be plenty fast. However, I did not see any option to buy a shorter mast for the Starboard foil, which would have made foiling at Kalmus during low tide questionable, and foiling in the Hatteras sound impossible. So all I could do to imitate Stroppo was to try to look a bit like him:

During the session, wind averages from the iWindsurf meter at Kalmus were mostly 15 mph, with a few readings of 17; gusts were mostly in the 17-18 mph range, with a couple of 20 mph readings. I tried to plane with the 6.5 m sail on my Skate 110 a few times, but either the wind was too light, or I have forgotten how to sail a "slapper" in marginal conditions. When foiling, the 5.2 m sail was mostly ok, and only a bit smaller than I like in the lulls; the 6.5 was plenty big, and I could get up onto the foil pretty much anytime I liked, with (at most) minimal pumping. After 12 sessions on our foil, and about 20 foil sessions in total, foiling already had dropped the "good day" wind definition from 18-20 mph to 15 mph (and probably 13-15 mph). Sure, I could have planed with a 7.8 m sail on the 70 cm slalom board, but that would have been a lot more exercise and a lot less pure fun :-).

Wednesday, July 10, 2019

Light Wind Foiling

Yesterday's wind forecast was light, but it predicted a slight increase in the late afternoon. When the local wind meter readings increased to 11 mph, Nina suggested to try foiling with her 7.5 m longboard sail to find out how low she could go. Here's yesterday's wind graph:

By the time we were rigged and ready to go, meter readings were down to 8 mph. This may be foilable for PWA pros with huge sails and foil boards, but Nina only had 3 or 4 foil sessions on our gear, and fewer than 15 sessions overall. For more than an hour, her board stayed solidly in the water, except perhaps for a couple of seconds after vigorous pumping. But then, the wind picked up just a bit, and for 20 minutes or so, she was foiling most of the time, getting nice, long, controlled flights. When we got back home, we looked at the wind graph:

The highest wind average reading was 10 mph, gusting to 12, for about 10 minutes (9 knots gusting to 10.4). To plane on windsurfing gear, she usually needs at least 13 mph on the big slalom kit, and perhaps 18 for her freestyle gear.

Foiling in 10 mph with pretty limited experience is pretty impressive. The sail certainly helped - it's extremely light, has a deep profile and a tight leech, and soft cambers. But it was not rigged quite right, and Nina has not yet figured out how to pump it really well with the foil, so there's some room for improvement. We also just ordered a Slingshot Infinity 84 foil, which is larger and should lower the planing threshold a bit more. Hopefully, though, the larger foil will mostly help to get me going in similar light wind. Even on foils, bigger guys need a bit more power...

Tuesday, June 25, 2019

Silly Grin

I can't wipe the silly grin off my face. What a great day! It was raining. The wind meter readings were at 20 mph for about 20 minutes, and that was after I had left the water. I crashed a lot. My top speed was 17.3 knots, and my distance sailed 14.6 km - both numbers that usually would indicate a terrible day.

But I was on the foil. I had spend about 8 hours repairing my 71 cm slalom board that had a large-scale delamination on the bottom. Here's a picture of the zombie board in its current state:

Well, the little zombie works  a lot better than old Skate 110 or Nina's Bic Nova 170 I've tried before, so I've been foiling every time I got a chance in the last week, even when we got enough wind to plane on regular gear. Here are today's tracks:
It was low tide, so I stuck with the 60 cm mast, which probably limited my upwind angles (at least that's my excuse :-).  I spent a lot of time pinching upwind, but I was just barely powered most of the time. That limited the number of jibe attempts to less than a handful, but even in several of these attempts, I was amazed how long the board stayed on the foil and out of the water. Here's a video of one of the attempts:
I was so surprised to still be foiling that I just held on to the mast and waited for things to drop down...

I'm not sure what it is about foiling - the silent flying? The gently touches? The 100% concentration that forces you "into the zone"? The fun of learning something new, and be scared by going about half as fast as when windsurfing? Whatever it is, I love it! So big thanks to Andy Brandt and the ABK Boardsports crew for giving me lots of opportunities to try foiling; Slingshot for sponsoring ABK; and Britt Viehman from North Beach Windsurfing for advice and hooking us up with a great foil.

Monday, June 24, 2019

GPS Tracks in Google Earth

One of the features in GPS Speedreader I like is the ability to export GPS tracks to Google Earth to create pretty "crayon artwork", as Fangy call the images. Here's an example:
There are a few options to customize what you see:
For example, you can set a minimum speed, so that parts where you were going slow are all shown in the same color. A variety of different color schemes are also available. Here's the "high contrast" colors for the same track:

For the lower graph, I had selected the "Include time stamps and speeds" checkbox in the export options. This enables the time line in Google Earth, so you can "play" your tracks. It also write the doppler speed data to the exported file, which you can see as a graph at the bottom of the image (to see the graph, you have to right-click on the "Speed graphs" item in the side bar, and select "Show elevation profile"; then you'll have to click on the "Doppler speeds" in the graph panel). The speed graph also reacts to moving the mouse over it by showing an arrow with the speeds in the image above. You can also select regions in the graph to get average speeds for the region. Go ahead and play with it - downloads are free at

Another new feature in the just-released version 1.2.8 is support for .sbn files from Locosys GT-31 GPS devices.

Wednesday, June 19, 2019

That's Why We Use Freestyle Sails

This is why we use freestyle sails:
With freeride sails, the arms are too short for duck jibes! My large freestyle sails needs to be replaced (or have 5 (!) panels repaired), so I used a 6.0 freeride sail. I did move my hand back before the jibe, and my hands did crossover to get closer to the end of the boom:

Friday, May 31, 2019

GPS Speedreader

In recent years, I had gotten a bit frustrated with the existing GPS analysis software. For some of the GPS prototype testing, there were too many bugs that just made the life hard. Furthermore, the "older" software that was developed almost 20 years ago can be painfully slow when looking at new, higher-rate GPS data from the Locosys GW60 or the Motion GPS.

So I wrote my own, and I'm releasing it to the public today. It's free software, supplied without any warranties - but if you want to send me "beer money" to support the further development, that's great! There's a donation button on the  GPS Speedreader Help page for that. 

This post will show a few screen shots, and point out a few useful functions in GPS Speedreader. Here's the main window:
The session shown is my recent 12-hour, 306 km session where Nina grabbed the #1 spot in the GPSTC women's ranking for distance. It's a large file, and trying to see the 1-hour results in GPS Results on my Windows computer took more than 5 minutes. In GPS Speedreader, the file opens in less than half a minute, which includes calculating the results for all GPS Team Challenge categories.

The main window is divided in a left side that shows the GPS points on the top, and the category results on the bottom. The right side can show up to three graphs: tracks on top, doppler speeds in the middle, and error estimates on the bottom. Clicking anywhere will select the point or region; here, I have selected the top 2-second speed. You can zoom in using the mouse scroll wheel or trackpad gestures:
There are a few different dialogs where you can choose what you see, what your time zone is, and so on. Here are the general preferences:
GPS Speedreader was developed specifically with the GPS Team Challenge in mind, and with a lot of feedback from GPSTC advisors. It's pretty easy to post session results to the GPSTC - just select "View results in browser" from the "File" menu. This will open up a browser page with the results:
At the bottom of the results, there's a button. Click on it, and a session page on GPSTC will open, with all the numbers filled in for you. You just have to add a comment and press the "Post" button. 

GPS Speedreader does not have all the functions that other programs have. For example, background images are not supported, and there is no "Jibe analysis" like in GPS Action Replay Pro. I will probably add some more features over time, based on feedback on the Seabreeze GPS forum. But with summer starting here, I'll hopefully spend more time on the water soon!

A couple of things are unique to GPS Speedreader, though, and deserve mentioning. One is the "Compare files" function which I wrote to make comparing different GPS units easy. You can open two (or more) GPS files from the same session, and Speedreader will compare the results in all GPSTC categories. It will even compare the error ranges, and flag any discrepancies with a yellow, red, or orange background. If you want to have a close look at the data, you can pick which columns are shown in the data table:
But that may be more for geeks. Perhaps a thing that's more useful for many is that Speedreader supports opening files by drag and drop. On Mac and Windows, you can drop GPS files onto the application icon; on Mac, Windows, and Linux, you can drop files onto the main window.

To read more about GPS Speedreader, check the online help at To download the program and start playing with it, visit

Tuesday, May 21, 2019

Oops She Did It Again

Seven years ago, Nina briefly held the #1 spot in the women's distance ranking on the GPS Team Challenge - the unofficial women's distance world record for windsurfing. Her distance of 202.79 km was beaten a few month later by  speedfalconster, who sailed 207.55 km - barely 3 miles more. Her record latest until 2016, when the Australian speedsurfer Cheryl sailed 226 km. Cheryl sailed at Albany, a wonderfully flat spot that is in my top-3 list of the best windsurfing spots in the world.

Nina tried to get the record back a few months later during our regular spring trip to Hatteras. During the attempt, she also competed in the first Hatteras long distance race, where she won the Women's Open division. Alas, the waiting for the start of the two races ended up costing her the distance record when the wind died in the afternoon, just three kilometers shy of Cheryl's record. Another couple of months later, speedfalconster sailed 248 km to be back on top.

Nina had talked about another distance attempt a few times before, although she'd rather keep working on freestyle tricks (unlike me, she considers sailing back and forth for hours as "boring"). However, we never quite got the right conditions .. until this forecast came along:
Planing winds all day, and 14 hours between sunrise and sunset! I was definitely doing distance! So Nina decided to play along and forget about freestyle for a day.

The setup was good, but not quite perfect. One issue were the relatively weak winds in the morning; a bigger issue were the strong winds in the afternoon, and the southwesterly direction which means high water levels and more chop. Unlike earlier distance attempts, we did not have a house right on the Sound, so some of the daylight time would be wasted rigging and derigging. Perhaps even worse was that our fitness levels were still just mediocre, after having fought several severe colds since returning from Oz.

But when we got up at 5 am Monday morning, the local meters showed 18 mph wind - it was a go! We left the house just as the sun was coming up, and started sailing at 7 am. Believing that the predicted forecast would happen, we both rigged a bit small - 6.3 and 7.0. That meant some pumping  from time to time to get going, and slim chances to plane through jibes.

We sailed for about 5 hours, knocking off the first 150 km with relative ease. During lunch break, the wind dropped, shifted, and then picked up. Here's the wind graph from the "KHK Resort" meter for the day:
I downsized from 112/7.0 to 99/6.3 by grabbing Nina's gear. However, the wind in the high 20s meant lots of chop, and I found myself blowing jibes and not feeling comfortable anymore. What's the point of sailing for 12 hours if you're not having fun? I replaced the slalom board with my Tabou 3S96, which handles chops a lot better. I kept he cambered race sail (Loft RacingBlade 6.3), but the combo worked surprisingly well, and I enjoyed the next few hours of sailing. Nina switched to her freestyle gear - Fanatic Skate 86 and Idol 4.5, which she often sails in crazy conditions. We sailed these combos until we both had sailed about 250 km - Nina had her World Record back! But she was not yet tired and wanted to go for another 60 km. I hoped to add another 100 km, but by then, the wind and chop had increased to levels where our sails where just too big. Nina downsized her Idol to 4.0, and I switched to a 4.7 wave sail.

Then, things did not go quite as planned. An hour later, Nina had to stop because her hernia was acting up. Her total distance for the day was 277 km, about 30 km above the previous record. Nice!

I never got comfortable with the 4.7 wave sail, going between underpowered to overpowered in every run. Maybe the difference from the super-stable race sail was too much; maybe the chop had gotten too high; or maybe I was just getting tired, but I was getting slower, and spent a lot more energy than before. As the sun dipped lower on the horizon, I also saw a lot more wild life - including jumping, spear-like fish that are know to occasionally pierce windsurfers ankles. So I decided to stop an hour before the sun went down, so we'd be able to put all the gear back into the van while it was still light. Here are my GPS tracks for the day (click on the image for a larger version):
These are Nina's tracks:
Here's the women's ranking for distance on the GPS Team Challenge:
Today, the wind turned to NE, which means much shallower and flatter water. We went for a quick sail, and it was lovely - if only we would have had such flat water yesterday! But NE wind here rarely lasts all day - today, it lasted just a few hours. Maybe we have to go back to Australia for the next distance attempt :-).