Wind farm risk to low-flying jets 

A controversial windfarm planned for one of Scotland’s most scenic areas is among developments that pose a potential risk to aircraft safety, aviation chiefs have warned.

More than 40 wind turbines over 400ft tall are planned for Lochluichart Estate, near Garve, in the Highlands, making them among the tallest anywhere in the UK. They will be visible from a series of famous mountain ranges including the Fannichs, Torridon and Strathfarrar.

Planes, including military jets, fly as low as 150ft in some exercises around the planned windfarm site although the normal limit for fixed wing aircraft is 250ft. Scotland has several tactical military training areas, including the Highlands and South Lanarkshire.

The Civil Aviation Authority (CAA) has issued written guidance to planning officials due to concern at the height and extent of such developments. Both commercial airline pilots and the Royal Air Force have voiced worries about turbine interference with flight radar.

Donald Northwood, the secretary of Garve and District Community Council, said last night: “Part of our objection to this windfarm application has been that it is a low-flight zone. These turbines will exceed 400ft but RAF Tornados fly at between 150ft and 300ft through Glen Achanalt.”

Turbines higher than 300ft must, by law, be fitted with lights so that airline pilots can see them. But the CAA is also concerned that the lack of lights on smaller structures could cause planes to crash through the blades when flying low.

Turbine blades also emit microwave radiation which can interfere with planes’ primary radar, secondary surveillance radar and navigation aids. The worry is that a build-up of wind farms could give the appearance of a ‘moving object’, making air traffic controllers believe there is an unidentified aircraft in its radar. This could have a potentially catastrophic effect if another plane is flying in the same area.

Northwood added: “The implication that microwaves could have an impact on flight safety makes the issue of the windfarm even more vital for us. I am sure that the public will be alarmed to hear this.”

The same flight control radar systems are used in helicopters, low-flying private planes, light aircraft and stealth bombers. An RAF spokesman yesterday confirmed that search and rescue helicopters and Tornado jets regularly operate in the Garve area.

He said: “We monitor all aviation developments carefully and when the CAA has concerns we will consider what further action we may want to take.”

John Urquhart, who lives one-and-half miles from the proposed windfarm site at Lochluichart, said: “This will be of great concern to the community. It is a sparsely populated area but that is not the point. A risk is a risk.”

The £89m project is planned for the Highland estate owned by Hamish Leslie Melville, 61, the managing director of international banking group Credit Suisse First Boston. He is being backed by windfarm developer LZN, which is a combination of Dutch wind farm giant KDE and Savills property consultants. The plans recently attracted controversy when it emerged that Leslie Melville is a former chairman of the National Trust for Scotland (NTS).

A spokesman for the CAA said it took action to warn Scottish councils of flight risks after planning officials recently received an application to extend the Hagshaw Hill windfarm development in Lanarkshire.

The proposal to build a further 20 turbines at the site was agreed last week just days after the biggest wind farm in the UK was switched on in Forth in neighbouring South Lanarkshire.

A spokesman said they would now monitor both ScottishPower sites after lodging their concerns during the consultation process.

He said: “We are concerned that a proliferation of wind farms in any one particular area may potentially result in greater difficulties for aviation than a single development would generate. The physical obstruction caused by a tall structure could be cause for concern as well as the effects that turbines and their blades can have on communications, navigation, radar and surveillance systems.”

The spokesman added: “We will look, on a case-by-case basis, at factors such as the proximity of the planned development to airports and airfields, flight paths and radar systems. We will continue to monitor aviation safety in relation to wind farms and take all necessary
steps to ensure that safety is maintained to the highest standards.”

Around half the planned wind farms for Scotland are in the country’s Central Belt.

The independent MSP Margo Macdonald last night demanded a review of the current planning process.

She said: “Do you think that the CAA is trying to tell us something? If the CAA is telling us that wind farms should carry a government health warning, it might have been a better idea to make their fears known before the second wind farm in the Forth area was agreed.

“We must take seriously the possibility that we can have too much of a good thing. With public safety in mind, the growing number of windfarms may soon pass saturation point across the Central Belt.

“I’m raising the matter with the Scottish Executive.”

The Executive has pledged that 40% of Scotland’s energy needs will be met by renewable sources by 2020.

By Arthur MacMillan and Siobhan McFadyen

Scotland on Sunday

29 February 2008