Downbursts

[ricki]

Some information regarding downbursts has been pulled together at:

http://fksa.org/viewforum.php?f=81

I can't recall having seen a dry microburst which may be somewhat common in your area. I have experienced wet microbursts several times, at least once while kiteboarding.

Local perspectives on this weather phenomena would be appreciated.

FKA, Inc.

transcribed by:
Rick Iossi

[RickHeninger]

This posting below I found very interesting, enough to copy and paste... I could see this happening to many... From what I understand, Mitch had a release but it was an older one with a little nub type thing that caught the loop...

Posted: Mon May 09, 2005 8:45 pm Post subject: New Rider & Corkscrew Of Death

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I received an email about something that happened last Friday to a new kiteboarder on his first time getting up on a board. Conditions were side onshore about 17 to 22 mph average 19 mph. The 140 lb. kiteboarder was flying a 9 m kite. The rider fell over, had one of his outer lines get caught inside a carabiner. He had used the carabiner to secure a knife to his harness. The kite started spinning, pulling him along about 1/2 mile out of control in bursts until the line broke. Kiteboarders should avoid wearing stuff that can catch or tangle flying lines. It is a good idea to consider using breakable line or sufficiently weak pull ties to secure possible entanglements, e.g. hook knives, etc.. His account is more interesting and impacting than this summary and follows below:



Don't use these for kiteboarding or anything else that can easily snag or catch line. Breakable line or pull ties might be a better option to consider. If they get tangled by line ideally they should break free.


Last Friday I launched the kite, got a foot hold on the board and launched myself for the first time. I'm thinking Ya I finally got the hang of this sport, I'm kicking Ass! So now I'm about 100 yards off shore. I start going back to the beach. All Right I'm kicking Ass, I'm doing it! Just before I get to shore I turn around and start going back out again. Again, Wow I must be a natural. But this time I didn't do too well, something tragic happened.

I got launched up in the air, lost control, and ate shit really bad. Some how one of the lines got caught on my harness and wouldn't let me go. I realized I was in a very serious position. The kite crashed into the water. I could tell that it wanted to launch back up again. It was feathering in the wind, changing directions, and was getting ready to do something wicked. These kites have a mind of their own, they want to go up no matter what your agenda is. The next thing I remember was a sudden jerk and their I was, getting launched up in the air and dragged through the water from 0 to 20 MPH in a second.

The kite started looping which is the worst thing imaginable ("the corkscrew of death"). It was going straight up then straight down over and over. The kite was literally circling in the air. I WAS SHITTING MYSELF AND THEIR WASN'T A THING I COULD DO ABOUT IT! I was getting thrown around like a rag doll. Then the kite would hit the water and I would get a breath. Before I could exhale I was back skipping across the water trolling for sharks with my body as bait.

I just bought a knife Wednesday and I said to my self, "I have to cut these lines. Do I really want to do that? They are like $50 a piece......" Then I got my ass kicked and dragged another 50 yards and said to my self, "If I don't cut these lines right now I AM GOING TO DIE!! I pulled the knife out, reach over just before the kite relaunched itself again, pushed the knife to the ropes, and the kite shot up in the air, and ripped the knife out of my hands in less than a second. I looked back and saw my brand new knife floating in the water. Before I could look forward again I was launched back in the air, came crashing down and started funneling saltwater as if I was at a Frat party. "OH MY GODDDDD. THE ONLY THING THAT IS GOING TO SAVE ME IS GONE. I AM SO SCREWED!!!!" I can't tell you how scared I was. That was the first time I really thought I could die. I was horrified. I was totally out of control.

I had to get unhooked from the line or it is over because I don't have enough strength to be tossed around anymore. The line was hooked onto the sheath of my knife out of all things. the very thing that was suppose to save my life I lost and got me into this mess. I opened the clip that was connecting the sheath to my harness. I wanted to take it off me. The line just snapped and broke. I guess it was too much stress. My kite was completely torn up and entangled with the lines. I was in shock.

That was the heaviest situation I have ever been in. I went through head on collisions. I have been held under water while surfing. I Got a surfboard fin stuck in my leg next to my femoral artery. I have had too many bike accidents to talk about. I have seen death face to face a few times in my life. This experience scarred the shit out of me more than anything I have been through yet. Writing about it is pretty funny but their wasn't anything humorous about this. The only thing I could think of while I was swimming back to shore was how glad I was that I bought my life vest 4 days after we talked about it online.

I went out and learned that I had been dragged over 1/2 mile downwind. I told some people about this but I don't think I will tell my family. It
might make them uneasy when I go out next week.

Thank you for the advise.
_________________

transcribed by:
Rick Iossi
http://fksa.org

[ricki]

This posting below I found very interesting, enough to copy and paste... I could see this happening to many... From what I understand, Mitch had a release but it was an older one with a little nub type thing that caught the loop...

I hadn't heard about that aspect yet. Do you know what specific type of bar/quick release Mitch was using? Does anyone know if Mitch tried to release the QR or even had the opportunity? In major lofting cases, i.e. high ones, the rider often has his hands more than full just trying to manage flight as if he was using a paraglider.

[Kenny]

Rick,

Mitch was using a snap shackle with a pin release. The shackle has a nub that can catch a chicken loop even after it is released. However, I spoke with Spencer who picked up the bar after Mitch's incident. He told me that the shackle was not released. I don't know if Mitch tried to pull the shackle release and it would not release under load or if he just thought he could ride it out. Mitch has rode out several microbursts in the past.

You asked for more information about dry microbursts. I am no meterologist, but I can tell you what happens from first hand experience. Usually, there are signs of a microburst that a fairly obvious upwind. Common signs are dust devils or a cloud of dust. Microbursts are usually accompanied with some cloud activity, but sometimes the clouds are distant enough that it is not obvious as to where the formation of the microburst occurred. Microbursts are common during the time of summer that we call the summer monsoon. Each day clouds will develop during the course of the day resulting in a thunderstorm in the late afternoon or evening. Microbursts usually precede the thunderstorms earlier in the afternoon. They are usually dry and the duration is very brief yet intense. Winds can range from 20 - 80 mph. The microburst that Mitch was involved in was much more powerful than usual. I would say from past experience that the typical microburst that I have seen had winds around 20 - 40 mph. The microburst that took Mitch was around 70 with dirt and dust flying so hard that the riders on the beach quickly lost sight of Mitch as he was dragged downwind. This microburst was very apparent to the other riders. However, they only had enough time to get into shore and drop their kites before it hit. I helped Spencer untangle his lines the following Saturday and I have never seen such a tangled mess.

Kenny

[ricki]

Hello Kenny,

Thanks for writing and providing all the additional information. I had a few more questions,

Rick,

Mitch was using a snap shackle with a pin release. The shackle has a nub that can catch a chicken loop even after it is released. However, I spoke with Spencer who picked up the bar after Mitch's incident. He told me that the shackle was not released. I don't know if Mitch tried to pull the shackle release and it would not release under load or if he just thought he could ride it out. Mitch has rode out several microbursts in the past.

Did the shackle resemble the one shown below? Also, the shackle was connected directly over the plastic of the chicken loop and not through a metal ring?

You asked for more information about dry microbursts. I am no meterologist, but I can tell you what happens from first hand experience. Usually, there are signs of a microburst that a fairly obvious upwind. Common signs are dust devils or a cloud of dust. Microbursts are usually accompanied with some cloud activity, but sometimes the clouds are distant enough that it is not obvious as to where the formation of the microburst occurred.

What is the furthest away you would guess clouds might be when a microburst is initiated that might seriously impact winds in your area? Would you say virga is normally visibly present or not necessarily in these cases? I assume it can be sunny where you are when one of these hit?

Microbursts are common during the time of summer that we call the summer monsoon. Each day clouds will develop during the course of the day resulting in a thunderstorm in the late afternoon or evening. Microbursts usually precede the thunderstorms earlier in the afternoon. They are usually dry and the duration is very brief yet intense. Winds can range from 20 - 80 mph. The microburst that Mitch was involved in was much more powerful than usual. I would say from past experience that the typical microburst that I have seen had winds around 20 - 40 mph. The microburst that took Mitch was around 70 with dirt and dust flying so hard that the riders on the beach quickly lost sight of Mitch as he was dragged downwind. This microburst was very apparent to the other riders. However, they only had enough time to get into shore and drop their kites before it hit. I helped Spencer untangle his lines the following Saturday and I have never seen such a tangled mess.

Kenny

I am amazed that Mitch was able to land after the first lofting. That shows quite a bit of board and kite handling skill. Do you think he would have had time to activate any quick release just before, during or slightly after landing?

Thanks,
Rick

[Kenny]

Rick,

Concerning the snap shackle. Yes, it is similar or identical to the one shown in the photo. I believe the shackle was tied onto a standard spreader hook. The chicken loop was secured inside of the releasable end of the shackle. He was also using an older bar that had a non-releasable chicken loop. So, if the shackle did not release, the only other alternative he would have had was to cut the line.

I do not know enough about microbursts to fully answer your question. Yes, it can be sunny when a microburst hits. However, usually it is a bit overcast and there is noticable cloud activity.

I think he could have had time to release after the first lofting. I have been lofted about 45 feet in a microburst (ithat was in 2001 - I drop my kite when I see them coming now) and I was able to release after the initial loft. Spencer told me that Mitch had control of the kite while in the air. I would think after being lofted so high that Mitch would try to release after the initial loft, but he often referred to tea bagging as controlled jumps, so I don't know if he tried to release and was unable or if he thought he would just ride it out. We can only speculate at this point.

Kenny

[ricki]

Hello Kenny,

About how many times would you say you have been hit by microbursts? How about some of the other riders on the forum? Would you have a guess as to how many might be noticeable from some of your launches in a given season?

From what I have read they seem to have fairly local influence, under 2.5 miles in area by definition. So, even though they may be fairly common it may be less common that the high velocity component of one coincides with your location before it dissapates.

Then again, it would seem that Utah gets its share of powerful damaging microbursts as in other areas. So, it seems to come down to luck of the draw somewhat and how soon you seen signs of one moving in and react to totally depower your kite.

The idea of a warning horn was made on kiteforum. This has been used for good effect in dealing with wet microbursts and other tropical unstable weather in Antigua and Cabarete for a few years.

Rick

[Kenny]

Rick,

I have only experienced microbursts 3-4 times, but I usually kite in the morning on south wind days when microbursts are more likely. The wind becomes more holey and gusty in the afternoons when microbursts are common. I personally would rather ride in light smooth wind than strong, spiky, gusty stuff. I would say that they are fairly common at Rush Lake. Most riders around here have had a brush with a microburst. Mitch probably had more experience with them than anyone else I know for a couple reasons: 1. He liked high wind days which are usually out of the south (the only time we would ever see microburst type conditions out of the north is during a frontal switch). 2. He worked as a roofer with flexible hours, so he would always be kiting on high wind days when other riders had to work. He rode his 5 meter many times this year.

A horn is a good idea. I bought a couple small ones at Wal-Mart, but they are not loud enough. I need to pick up a big one at a local marine products store.

Kenny

[ricki]

Hello Kenny,

I hear you about uneven gusty wind, it really isn't much fun. It can also really take a bite out of you as well. We have had three days of such conditions with the passing of Hurricane Dennis.

So, the lake falls in an extended valley running south from Great Salt Lake forming the Rush Valley. Is the launch area located to the left of "Rush Valley" on the photo below?



It looks like you have some mountains to the east and west probably generating some fairly gusty winds through rotor? Is the wind more even out of the north off the big lake?



Aside from time of launch, what other things do you consider when trying to avoid microbursts? What visual signs do you first notice? I imagine that routine testing of quick releases is fairly popular at your launches.

Regarding air horns, you could order online as well such as: http://www.westmarine.com/webapp/wcs/st ... ctId=93252

Four sharp blasts, repeated seems to be a fairly common emergency signal.

Thanks for all your input.

[newkiteguy]

I picked up the book Steve recommended in his post and man, what there is to learn!

These beasts are very real and not so hard to know when they may be likely to occure. Some simple steps can be taken to check, the most basic being if there are dark, textured clouds, chance of thunderstorms in the forecast, then most likely there may be micro's out there.

There are many other sources and things to look for. They had a huge stacks of these books and I also hung around the Soaring Center and watched a weather video. Lots of help.

The book is "Understanding the Sky". The lady there gave me the UWA deal, so it was under $20 with tax.

[Marty Lowe]

So, the lake falls in an extended valley running south from Great Salt Lake forming the Rush Valley. Is the launch area located to the left of "Rush Valley" on the photo below?

It looks like you have some mountains to the east and west probably generating some fairly gusty winds through rotor? Is the wind more even out of the north off the big lake?

Aside from time of launch, what other things do you consider when trying to avoid microbursts? What visual signs do you first notice? I imagine that routine testing of quick releases is fairly popular at your launches.
Thanks for all your input.

Rick,

IMHO

Yes, The launch is to the left of the words "Rush Valley" in the top photo.

The common belief is that the mountians on both sides "pinch" the wind into Rush, helping the flow.

The North wind at Rush can be very smooth, unless there is a little west cant to the wind.
Most of the South winds we get at all of our locations are quite gusty, compared to the North winds we can get.

Saturday was quit nice 13M (south winds) at Rush, no clouds in the sky before 1:00, but there were small dust devils to the south of the lake. It is getting so dry, that it does not take much to get the dust in the air. I find myself looking upwind more for that kind of thing. The forcast was for slight chance of thunderstorms. The wind basically died by 1:00

There is a lot more talk of safety, and helping newbees, but there was a guy that was locked into a carabeener. we gave him shit, but to no avail. If it would have been stronger winds (the wind was almost dead by then) I may have refused to launch him. I think from now on. I will refuse to launch anyone without a good release.
Some of us discussed with Mitch his release, but Mitch was a hang on type of guy, I don't think any current release would have mattered.



-Marty