You just can't win with enviromentalist!

[riddler 0]

Not one person has mentioned just how dangerous these things are to skydivers. Don't you remember Terminal Velocity?

Trapped on the surface of a sphere. XKCD

[kallend 2,026]

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Don't you remember Terminal Velocity?

I try not to.

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The only sure way to survive a canopy collision is not to have one.

[rushmc 23]

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>Wouldn't you like to have a bunch of those in your yard?

I'd be happy with one!

Me too! Rent starts out as a flat fee per year with potention future revenue sharing

"America will never be destroyed from the outside,
if we falter and lose our freedoms,
it will be because we destroyed ourselves."
Abraham Lincoln

[rehmwa 2]

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Got a cat about a week ago. Poor little bastard darted out of a ditch at night. I didnt have a chance to try to miss it.

lucky you, they are quicker here, you really have to react quick or they get away.

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Driving is a one dimensional activity - a monkey can do it - being proud of your driving abilities is like being proud of being able to put on pants

[masterrig 1]

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>Wouldn't you like to have a bunch of those in your yard?

I'd be happy with one!

You sure wouldn't have to worry about power! Sell-off the 'excess'... it's a win-win!


Chuck

[Muffy 0]

Revive:

Wow - colectively ya'll have about 17,000 jumps. How many of those were directly downwind of an industrial wind power installation?

[Amazon 7]

I have a bunch of jumps at Byron.. Bay Area Skydivers...it is a windy place...

Sometimes I wish they would turn all those fans off

[Rookie120 0]

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Wow - colectively ya'll have about 17,000 jumps. How many of those were directly downwind of an industrial wind power installation?

I have about 25 at Byron. Whats the point?

If you find yourself in a fair fight, your tactics suck!

[Muffy 0]

Someone said NIMBY about wind turbines in a skydiving forum - that caught my attention.

One might not mind them in the backyard, but if they were in the front yard, would we have a problem landing into the downwind plume off of say, 25 Vesta V90's 4,000 feet off the landing area?

[billvon 2,990]

>but if they were in the front yard, would we have a problem landing
>into the downwind plume off of say, 25 Vesta V90's 4,000 feet off the
>landing area?

Well, everything standing up in a stiff wind is going to generate turbulence. It will likely be worse than trees, not as bad as buildings. I would imagine the 10:1 rule would apply as always.

So in the case of the Vestas, you'd want to be about 3/4 of a mile from them to reduce the odds of hitting turbulence. 4000 feet should work. Needless to say, it would be rather stupid to put a drop zone in an area downwind of the turbines; they site turbines to get the most, not the least, wind. Even Byron is considerably lower than the majority of turbines that are within sight of the DZ.

[Muffy 0]

>>it would be rather stupid to put a drop zone in an area downwind of the turbines
Agreed - but not a lot of new drop zones are being built around the world. What is being built however are an awful lot of industrial wind power plants and it's not stupidity that gets them built adjacent to an existing rural drop zone. It's just capitalism wearing the latest fashionably environmentally friendly disguise over greed.

>>the 10:1 rule
That's an interesting rule - how does that go? You need 10 feet of horizontal separation from an object for every foot in height of that obstacle to avoid potential wake turbulence. Where's that documented?

Up until now the kind of objects we've had to factor in were largely stationary right? Does a 10:1 rule apply when the object is a big as a 747 with blades alone weighing in at 40 tons spinning around as fast as 19 times a minute. Say hello to one Vestas V90. Think 10:1 still applies?

Who else knows about wake separation? There were some problems with big planes and that not so long ago. Check out what the International Civil Aviation Organization (ICAO) says about wake vortex separation at http://en.wikipedia.org/wiki/Wake_turbulence for objects about that size and mass. If we could for a moment consider a single set of those 40 ton turbine blades as a Medium class "Maximum Take Off Mass" (MTOM), and someone landing under canopy as a Light class MTOM (hell, even someone landing the jump plane fits into that class), then should the landing separation from a single industrial wind turbine be…5 nautical miles? That's 30,380 feet - 76:1. But then again, the ICAO recommendations don't have to factor in that there might be 50 other Medium class preceding aircraft flying right next to each other in that wind power plant?

So, do we really know what a safe distance from an industrial wind power plant is under canopy?

[billvon 2,990]

>What is being built however are an awful lot of industrial wind power plants
>and it's not stupidity that gets them built adjacent to an existing rural drop
>zone. It's just capitalism wearing the latest fashionably environmentally
>friendly disguise over greed.

Of course. On the plus side, if the turbines are a sufficient distance away, they will reduce maximum winds and allow jumping on (slightly) more days per year.

>Up until now the kind of objects we've had to factor in were largely
>stationary right?

Yep. Which is both good and bad. A moving object creates a transient vortex in a given point in space; a stationary object creates a more consistent (spatially) vortex. Hence the greater problem of following a canopy (or a 747) in to a landing as compared to crossing its trajectory at a 90 degree angle.

>So, do we really know what a safe distance from an industrial wind
>power plant is under canopy?

Nope - although I strongly suspect they are far less dangerous than buildings of a similar height.

[Muffy 0]

>>reduce maximum winds
along with increased in tubulence...

Here's some shocking news about being downwind from "the farm":

"For the first time, high-resolution SAR-derived wind speed images are utilized to identify regions of reduced wind speed and high turbulence intensity (i.e. wind wakes) downstream of wind turbine arrays"

"A decrease of the mean wind speed is found as the wind flows through the wind farms, leaving a velocity deficit of 8–9% on average, immediately downstream of the wind turbine arrays. From this point, wind speed recovers to within 2% of the free stream velocity over a distance of 5–20 km depending on the ambient wind speed, the atmospheric stability and the number of turbines in operation"

"The standard deviation of SAR-derived wind speeds is an indicator of turbulence intensity. Added turbulence intensity downstream of a wind farm is found for 7 of the 19 cases."

I do believe I'll buy that paper: http://tinyurl.com/5gbbun

[georgerussia 0]

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There have long been complaints about the bird kills for the windills along I-580 at the Altamont Pass. In response the smaller windmills have been replaced by fewer, big ones.

If all those so-called environmentalists reduced THEIR electricity usage, we'd probably need no windmills.

* Don't pray for me if you wanna help - just send me a check. *

[Gawain 0]

I've not been close enough to any of these farms to know for myself, but I often hear about these wind farms being rather noisy.

Is the noise from the generators of the windmill? Or is it from the fan blades? How noisy are they and can they be perceived as a point of noise-pollution?

So I try and I scream and I beg and I sigh
Just to prove I'm alive, and it's alright
'Cause tonight there's a way I'll make light of my treacherous life
Make light!

[Darius11 12]

Anyone think that maybe this

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The federal suit, filed in U.S. Western District Court in Austin, said the turbines could kill untold numbers of migratory birds and damage the bay. It seeks to overturn the decision by the Texas General Land office, which Patterson heads, to allow the projects to be built without environmental review or input from the public. The suit contends that the Federal Coastal Zone Management Act of 1972 and the Texas Coastal Management Program require a permit process for any energy generation facility on the coast, including wind farms.

I don’t know much about the group or the area, I do know that we have in the past done things without enough review. These things were thought to have been a good idea at the time but ended up being more harm in the long run.


Could it be that this is one of these things? That it could effect the bird population in such a way that it would effect the ecological balance?

I'd rather be hated for who I am, than loved for who I am not." - Kurt Cobain

[billvon 2,990]

>Is the noise from the generators of the windmill? Or is it from the fan blades?

It's from the blades moving fast. (Tip speeds can be very high in strong winds.) It's sort of a cross between the sound a sailplane makes when it's making a high speed pass and a helicopter.

>can they be perceived as a point of noise-pollution?

Of course; anything (from pine trees to powerlines) can be seen as a source of wind-induced noise. Since they tend to be on ridges where there's a lot of wind (and few people) it generally isn't an issue. In populated areas it can be.

Early on, people were mounting wind turbines on their houses to save money on masts. That turned out to be a very bad idea, since the vibration is transmitted through the mast.

[Muffy 0]

Research and excessively documented experiences from those living next to them suggests it wouldn't be a lot of fun or healthy to live as close to that sort of continuous noise as the developers think you can.

http://www.livinginnewyork.org/health_effects_of_wind_turbine_noise

A "wind power plant tourist" wouldn't be exposed long enough to get really annoyed though. (Seriously - the industry suggests to small communities that an installation will attract tourists - they'll even offer to put up a cute observation deck and everything.)

Not sure if a student under radio would be able to hear it in flight ("Jumper #3 - give me a left 90 left 90 to avoid the large spinning things"), so it probably would not much of a distriction unless you can perceive the low frequency noise - some people are more senstive to it than others though.

The shadow flicker can cause seisures though...

>>Jumper #3
This is funny but it also assumes Jumper #3's radio would even receive the transmission - moden wind power plants... they disrupt radio signals and RADAR...

[n23x 0]

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excessively documented experiences...

I like that expression. Are these 'excessively documented experiences' due to actual, legitimate physical discomfort? Or because the yacht club doesn't want an 'eyesore' in sight?

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home » groups » WOW - We Oppose Windfarms

Seemed like a good place to acquire objective data, right?

.jim

"Don't touch my fucking Easter eggs, I'll be back monday." ~JTFC

[rehmwa 2]

windfarms are slowing down the earth's spin

so all you naysayers don't come crying to me when the moon crashes into Ohio

stupid money grubbing developer envirofreaks

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Driving is a one dimensional activity - a monkey can do it - being proud of your driving abilities is like being proud of being able to put on pants