The article doesn't say how the windmills interfere. Without a why it sounds pretty hysteric to me.

Reading between the lines in the article, it looks like one test was run on one wind farm. That sounds pretty conclusive to me!

Seriously, unless someone has their life savings invested in oil stocks, I don't see how ANYONE can be against wind farms. Why all the hate?

And just who is the British military going to detect attacking from the northeast? The Norwegians? The French? Germany?

I think energy independence will provide much more security than a radar defense against World War II opponents.

Well, same can be said for the sonar protection area off the coast of So. California that the Navy wants exemption from.

Like Samoa is going to send nuclear submarines to attack Disneyland?

myth

I could be wrong because I only had a brief read but from what I have read the affect isn't all that bad and if a radar from one direction misses an aircraft would another from a different location fill in the shadows? I think it would.

There is no need to limit wind farms, the military need more radars.

Have a read, BWEA - Radar Aviation Interests

I didn't know Al qaeda has an air force?

I think 9/11 shows you don't really need an airforce to do a lot of damage with airplanes.

Defense radars do more than track incoming warplanes... they also track civilian craft, and can/will notify when civilian craft go off course.

What rot. Set up the windmill farther away from the radar dish,
how hard is that...
.
_H*

Must be dangerous with all those windfarms that are built very close to populated areas or cover a swath of land that extends for hundreds if not thousands of miles!

windmills might affect low altitude radar, but unless someone is gonna invade by helicopter, and that would be from canada, mexico, or a very large (detected days in advance) ship off our coast, we have nothing to worry about...

now england is vulnerable to a degree, but not very much... monitor your seas, you will be fine... iow, unless they create blind spots in satellites as well, someone is simply blowing smoke.

Build Small radar installations on the other side to cover the blind spot, when the enemy bombs those you know they are coming. Or be a nice country with less enemies.

Wind farms are built where they are built to get the most consistent winds, it isn't easy to just build them further away it costs efficient operation.

Not just low altitude. An obstacle 300 feet above the radar dish at a distance of one mile from the dish would hide an airplane flying at 5000 feet at a distance of 17.5 miles. It would hide an airplane flying at 15000 feet at a distance of 50 miles. And that assumes the earth is flat, not round. A passenger jet can travel 50 miles in less than 10 minutes, a military jet could do it even faster.

So yeah, I could understand how the UK's military might take offense and someone building obstacles near their existing radar facilities.

Large scale windfarms may well have environmental impact far beyond radar shadow.

See this: Sea birds might pay for green electricity - earth - 07 May 2005 - New Scientist

In California, there is a significant movement to get rid of at least the worst offenders, built in the 1970s without the benefit of any environmental studies.

Our bombers are nape of the earth capable, and presumably so were the Soviets back in the day.
Satellites don't see everywhere at once.

There are some considerations:
1) All present day radars use the frequency distortion (doppler shift) as a key element in the signal processing to detect, track, and classify moving objects. The windmills create a lot of doppler shift, greatly reducing the sensitivity. It is detecting the low altitude targets that are the key function of most defense radars. Note that it is when the radar is seeing the windmills from the side that is the worst condition. Until lately, big doppler shifts from high structures was non-existent.
2) There is nothing preventing a terrorist from flying a Cessna or big RC airplane into a major city from a barge or tanker ship. It might be a big joke to some, but if someone does plow a Piper Cub into a school, then it will not be so funny having blind radars. (PS Some terrorist are willing to wait for the right conditions.) Many do overreact to the terrorist threats, but a great many smugglers would take advantage of this if possible.

That said, stopping the building of windmills is not the right answer. It would be ironic if the windmills were stopped, the power went out at the radar stations. There are ways of solving this with some sensible thinking.

Well, not exactly. But yes, relocate the radar towards the desired detection directon, away from the Wind-Mills.

FL_Prius_driver is right,

Modern radars use doepler to decern targets from ground reflected signals. The ground reflected signals do not have velocity with respect to the radar (unless they are 100 meter diameter whirling blades), and have no doepler shift. This is accomplished with digital signal processing, which can be designed to have a very sharp, non ringing filter to reject the ground clutter signal. Depending on the direction of the wind, the blades could be rotating perpendicular to vector towards the radar and pose minor effect. Or parallel to the the vector towards the radar and cause false detections, or noise at speeds that a plane could fly at.

These radars are so good, they can easily see high speed cars on roadways a hundred miles away, which then disappear when they come to a stop, or turn perpendicular.

Which is why the Audubon Society is in favor of wind farms - because everyone knows how much they HATE birds.

so these radars are so good they can detect terrorist attacks? or maybe they just detect the infrared signature of high explosives loaded on board