Windfarms and military radar

[rogcal]

Sorry to invade your forum with this query but I don't think the real experts I need to hear from live in my usual forum (private flying) and I'm hoping someone on here can help!

After almost 4 years of concern Scottish Power last week withdrew their application to develop a 6 turbine wind farm on land approx 1km from my house and strip.

On the face of it some would say good news but Scottish Power have mad it quite clear that they will resubmit the application next year when they have resolved the problems that led the MOD to object to the development on aircraft safety grounds i.e the turbines would affect the precision approach radar at Cottesmore and to a lesser extent the radar at Cranwell.

It seems they are hopeful that "new technology" will resolve the matter and my question to those that are in the know is, "is there there something being developed that will resolve the problem in favour of wind farm developers.

I have my own theories on how it could be acheived i.e. transponders on each turbine blade tip and software developed to recognise a blade as such and removing it's return from the display screen.

Any assistance may help put a lot of people's minds at rest if such a technological breakthrough is still years away or not, as the case may be.

Thanks.

[FlightTester]

Over here in the wilds of Kansas we have a number of windfarms and a great deal of storm tracking doppler radars. The windfarms cause problems with the radar due to the echo from the blades - to be expected. The great thing with doppler radar is that it's looking for things that are moving (Doppler Effect), the only movement on a windfarm is generally the blades - the farms themselves are stationary. Our Met folks have learned that if a large return that looks like a storm is stationary, then it's probably a windfarm. Shouldn't be too hard to do likewise with a Harrier or Tornado on approach at ~160Kts i.e. radar blip moving across the ground at 160Kts - probably not a return from the windfarm!

Radar can also be "sector blanked" as far as I recall. So anything in a certain sector can be deselected so as not to show a return. Unless the proposed site for the windfarm is on the extended centerline for the runway at Cottesmore (which if I remember from my time there is 04/22) I would have thought that would be the easiest option.

[rogcal]

Thanks for that "Flight Tester".

So, the way I read your response is that as long as the wind isn't blowing and the blades are standing still, it's OK to fly our Harriers and Tornados and if the radar is sector blanked to not pick up returns from the wind farm, I'd better not operate from my strip next to it, as I won't be seen either!

I didn't see a punch line, so you must be serious.

What intigues me is that if a storm is an area where wind farms are located, the storm is by default going to cause a disturbance to the atmosphere and the consequent wind is going to turn the blades (the tips of which can reach 200mph as in the case of the Vestas V90 turbine) and if that's the case how could the doppler radar differentiate between a blade tip arcing through the air at 200mph at elevations between 250 and 500 feet and a Tornado/Harrier travelling at a similar speed.

Of course I could be way off beam here and have completely missed your point but one comment you did make had me conjuring up pictures in my mind of wind turbine towers being on wheels, so they could move around when a stationary storm is in the area and help your met guys work out which is which.;)

[FlightTester]

and if that's the case how could the doppler radar differentiate between a blade tip arcing through the air at 200mph at elevations between 250 and 500 feet and a Tornado/Harrier travelling at a similar speed.



Radar is capable of processing in 3D. So lets think of this as a time/distance/speed equation. The blades are rotating at 200mph (speed), and they're 250ft high (vertical distance), therefore in 30 seconds (time) the radar return should have travelled approximately 1.5 miles along the ground (horizontal distance). If the return that the controller is looking at has a speed and vertical component, but no horizontal component, then it has to be a rotating object that's not moving - Windfarm.

To answer your other question - when you're out and about presumably you're SSR equipped i.e. a transponder and squawking 7000, SSR is colocated on the primary radar - generally speaking the controller is looking at your secondary return, not your primary one.

[rogcal]

Wood and fabric with no transponder!

It's uncontrolled airspace and MK1 eyeball is the primary collision avoidance technology.:eek:

[FlightTester]

Ahh! Mk1 eyeball and climb to above 2000ft as quickly as possible then!

I used to fly along the Penines quite a bit - Blackpool - Kirby Lonsdale - Lancaster - Blackpool. It's quite interesting to watch a Tornado following the M6 as a navigational tool 1000ft below you!

Good Luck and Clear Skies

[Seldomfitforpurpose]

Nimby :=

[NorthSouth]

rogcal: for someone in your position the effects of the wind farm on radar will have little or no impact because I imagine you would rarely, if ever, want more than a Basic Service from Cottesmore so they're not looking to identify you on radar anyway. Your best defence is simply calling them on the radio. You then become known to them and they can take you into account. There are no solutions to PAR on the horizon and the effects on surveillance radar aren't likely to be solved in a year. Then again the RAF has been dealing with wind farm and other clutter on radar quite happily at many of its airfields ever since radar was invented. It's nothing new.

NS

[danieloakworth]

Rogical,

I do a bit (quite a lot actually) of work in this area and am familiar with the site in question. Yes Scot power have withdrawn to save themselves getting refused. MOD had made it very clear that they were opposed to the development and were not about to change their opinion. Scotpower have a history of mitigating aviation concerns not least in Glasgow where an additional radar was procured to cover a gap in coverage created by Whitlee Farm wind farm. This solution isn't applicable in Lincs due to lack of the terrain shieilding needed for the new radar. If you have a look at the BWEA website there is a fair bit of info on emerging technologies. The reality is that there is a fix on the way and it is likely to come from a mix of solutions, rather than a single technology. That said the RAF operate beyond obsolete ATC radars which makes it difficult to apply the sort of modern mitigation that your average small regional airport can accept.

Bottom line if you're an anti, then forget aviation issues as they are solveable in the long run.