maximum speed jump.

hi all. as i'm pretty inexperienced from a sailing perspective, i'd like to know whether anyone has topped 25mph on an ai. yesterday i sailed off newquay in strong gusting south westerlys, 20 -30 mph. due to a fear of tipping over, i had my sail slightly furled. i was reaching out towards the cribbar then reaching back in to the town beaches. i could definately feel the lift and speeding up as the set waves lifted my stern and shot me forwards. my gps registered 25.4mph and my previous fastest was 11mph. as i carry my gps in the ai side pocket so it really doesn't shift at all when sailing, and i only turned the gps on as leaving the harbour. what distance does one have to travel for a gps to measure speed. or, over how many metres would i have to sail at max. speed to record a max. speed.

adventrue before dimentia..

tw

Wow!! Best I have yet achieved is 11.? Mph. Though surfing waves with wind push too should def lead to faster speeds. Thrilling ride for you huh

_________________
2010 Hibiscus Adventure Island

Only one day have I broken 20mph...

from a 2009 post:
If you can minimize the water resistance, and the wind and waves are just right, you can really get going.

In 2006 here in Maui (a month after getting my AI's) I got just the right conditions one day with many fast runs many 22's & 23's and finally a 28mph run on the GPS. Fastest seems to be when the wind created long wind waves (miles long). I just sailed along the tops of the waves, with less water resistance. I later found the readings were a little high from the gps bouncing around (I didn't have it mounted yet). I also found on returning home that a Small Craft Advisory had been added after I had left for my sail.

I no longer try that as I've had discussions about what would happen if something broke at that speed (thanks dear).

Above about 10mph the hull hums from planing.

Since the beginning of 2007 I've kept a log with statistics.

http://www.kayakingbob.com/sailing-log

09/22/2007 - Three of us were sailing a beam to broad reach doing 8-9mph when a VERY strong steady gust came for over a min. pushing all three of us (in formation) to 19.7MPH! We could see each others boats but couldn't see each other because of the spray off of the hulls reaching at least 1/2 the height of the mast!

That's my two big wind stories, On sailing trips (not fishing) I try to break 10mph. In good conditions I average over 5mph including drifting during snacks and lunch.

Stay safe.

http://www.hobiecat.com/community/viewtopic.php?f=71&t=13503&hilit=fast&start=24

_________________

Hobie Island Sailing since 2006

Mate, you're mad enough to be an Aussie!

_________________
Cheers, Max ● TI: the "Yella Terra" ● Website: www.MadYakker.com ● YouTube: madyakkermax

thanks for the replies. ive thought over my sunday sail and remembered initially leaving the harbour and reaching across for about 400m. this was towards shore with running swells and a full sail. the speed was exceptional and my rudder, at speed, became totally unresponsive (although locked down). the bow was dipping under as the swell lifted the stern and it was a very wet ride. after two runs like that i reefed in some sail and had a better time with increased rudder control. it was very windy so still a very wet ride, but exhilerating. ive used my gps on every sail, mainly to record duration, max speed, avg speed, distance covered and to keep track of time. i have no reason to doubt it, as the track record is showing my sail for the day. im almost reluctant to delete the detail, as i dont know if i will ever better it. i will try though.

Well, if that was meant for me, then I'm honored!

_________________

Hobie Island Sailing since 2006

Those are speeds (20s) I will never reach in my AI. You do have to be careful w/ something like a max speed reading. GPS errors do occur. An occasional error does not significantly affect "speed" or "average speed," but, it can affect a single reading like "max speed." When I first started sailing my AI, I would lay my GPS between my legs on the flat hatch cover. In that position w/ pedaling, I would get very irratic readings for max speed.

I frequently leave my GPS in the side mesh pocket. It seems to give good readings there.

Keith

_________________
2015 AI 2, 2014 Tandem

"Any intelligent fool can make things bigger and more complex ... It takes a touch of genius and a lot of courage to move in the opposite direction." A. Einstein

"Less is more" Anon

the AI's must be so much faster or have a lot less resistance in the water. i can't get my TI over like 9mph according to my gps on my cell phone. i can't even imagine what 15 would feel like let alone 20 +. i'm a little disappointed cuz i thought the TI would somehow be faster than the AI due to the increased sail area but it actually seems a bit slower from what i can read hear.

thats crazy fast by the way.

The AI is only really designed to go about 8mph, and the TI about 9mph. You need the right conditions to to gain 2-3mph on top of that, including waves you can ride moving in the right direction, strong winds from the right direction and no smaller waves or conditions to slow you down.

I can reach 10mph on the AI on trips fairly often, but only for a few moments at a time riding a wave. A really nice wave and wind might break 10mph for 30 seconds or so. I broke 11mph a few times on one trip solo in the TI, but the spacing of the waves need to be further to fit the longer hull in between.

Anything above that is more a freak of conditions, and is unexpected, and thrilling (read scary!)

Also, the TI takes a little bit more time to start moving, but sails a bit faster in the same winds than the AI, but also (at least for now for me) takes more work when it gets in winds above about 18mph. I'm still learning to tame her.

_________________

Hobie Island Sailing since 2006

I've had a garmin foretrex for several years and regularly wear it jogging, skiing, paddling and sailing. The max speed readings from it are typically so far out of the realm of the activities I'm doing that I discount the value of the data. Perhaps the extreme readings are produced by arm movements. I don't know but the data seem to register extremes of speed that I know I never approached.

Timo

I find that my Garmin GPSMap, which always produces consistent readings when I mount it in the car, gives wild maximum speed readings when I carry it bushwalking, so yes, it seems to be a result of sudden short-term movements, like swinging your arms. I guess it's a function of how often it reads your position in calculating your speed. Say you were marching with the GPS in your hand and it checked your position at least twice in the time it took you to complete a full step cycle (left-right-left). During the half of the cycle when the hand carrying the GPS was swinging forward, it would record a speed of about twice your average marching speed. Likewise, if it records your position several times per second, the boat would only have to lurch forward momentarily on a wave to record a high maximum speed. I have tried setting my GPS to record a reading on the track log every second and when I analyze the log later, the highest speed recorded for any single one-second leg is less than the maximum speed which the GPS has indicated for the trip.

_________________

I also notice the difference between Max speed and the Max speed of the track log.

When I had the over 20's mpg reading it was with my Garmin etrex Vista also leashed above the middle hatch, so it was bouncing around. On the other hand, I've sailed over 10 mph often since, and we were going LOTS faster than that! So I may not have been actually going the 28mph reading, but it was fast! Fast enough that I was too busy to look at the GPS!

All of my readings since that day, the Vista was held in a Ram Mount made for it and in the last year with the GPSMap in it's Ram Mount. So no movement beyond the boats movement.

I can also tell you, on the 09/22/2007 19.7mph run, we created large rooster-tails off the bow that made it imposable to see each other in our boats. I've never seen that before or since.

But finally, if you asked me to get an AI (or TI) over 12mph, I probably could not do it without shear luck.

_________________

Hobie Island Sailing since 2006

24.5mph (45.4km/h) sounds like a GPS error to me. That is pretty common.(max speed setting)
They go alright, and I have been out in high winds, but I never have been even close to that.

I think the fastest I have gotten was like 10-11mph because a wave gave me a boost while on a fast reach. I do think the 20+mph speeds are possible though, because I think waves travel at 20+mph, so if you can catch a wave it should work.

http://www.oceanographers.net/forums/sh ... cean-Waves

"1.Deep water waves

Velocity of wave energy through water determined by wavelength

Longer waves move faster

Use period as is easier to measure than length

Speed (m/sec) = 1.56 x wave period

Typical 8 second trade wind wave moves at 12.4 m/sec=28 mph "

I agree with this estimate as well, in NC we have to go out 40-50 miles for pelagic fish, on the way back in we have to ride the swells, we would be going about 28-30mph and you could tell we were moving very close to the speed of the waves because we would end up riding the waves a lot.

One note about GPS speedometers, they are subject to errors/dropouts, and the faster you go, the more accurate they should become.

Unfortunately, our boats don't go fast enough to really get good readings, which seem to improve above 20 mph in my tests.

Water speed, (like air speed) is relative anyway. The feeling you get when you're already going "full speed" and then a gust kicks you in the pants - priceless.

_________________
The Wind Is Your Friend...