Onshore Wind: Aeronautical and Military Impacts

Aeronautical Issues

Wind turbines can have an impact on aviation activities, typically on radar systems or on low flying. In 2001, BERR formed the Wind Energy, Defence and Civil Aviation Interests Working Group to consider the combined interests of wind farm developers, aviators and government. This group, with representatives from the Ministry of Defence (MoD), the Department for Transport, the Civil Aviation Authority (CAA), the National Air Traffic Services (NATs), the Airport Operators Association, the British Wind Energy Association and government, has produced guidelines to facilitate the development of wind energy so as to meet the UK Government’s targets, while recognising the interests of civil and military aviation.

The guidelines explain Government’s policy and the need for wind energy, the issues relating to the potential impact of wind farms on aviation activity, and the planning and consultation process.

The Consultation Process

The MoD, CAA and NATs have a statutory duty to safeguard certain sites and airspace from radar interference in the interests of national security and for the safe operation of passenger and military aviation - this duty was restated in the 2003 Energy White Paper.  Developers are encouraged to consult voluntarily with these bodies before their formal planning application is submitted in order to identify and, if possible, resolve issues.

Consultation with these bodies happens through a standard BWEA Wind Farm Developers Application Proforma contained with the guidelines in which developers list the exact locations, dimensions, construction details and output of all proposed turbines. Completed proformas are submitted to the MoD which consults with its various departments, as well as with the CAA and NATs. If a site falls within 30 kilometres of a safeguarded aerodrome, the CAA generally devolves responsibility for safeguarding the aerodrome in question.

Each development is assessed on a case-by-case basis. The CAA and NATs will object to wind energy proposals that they feel could adversely impact en-route aeronautical radar coverage.

You can find further information in Civil Aviation Authority: Publication CAP 670 -Air Traffic Services Safety Requirements.

The MoD submits holding objections to all wind energy proposals within line of sight of air defence radars, unless the developer can provide evidence that it will have no impact on the radars. Proposals within tactical training areas are also likely to raise objections.

The MoD has also placed safeguarding zones around other facilities. For example, it has imposed a precautionary 30 kilometre radius zone around a seismic monitoring facility at Eskdalemuir. The facility constitutes a key part of a global network of facilities monitoring the current nuclear test ban treaty. Wind energy proposals within the safeguarding zone will be opposed. The MoD will make a holding objection pending more detailed evaluation of proposals within a 30 kilometre and 80 kilometre radius of the facility. However, the safeguarding zone is being reviewed following detailed analysis of the impact of wind turbines on the seismic array.

The Wind Energy, Defence and Civil Aviation Interests Working Group is working to simplify and speed up the pre-planning consultation process and to develop a common and transparent assessment methodology.

Aviation Plan

In addition to work to improve the processes of consultation and assessment, there is a substantial amount of other activity going on to identify, develop and implement solutions to the potential impacts that wind turbines can have on radar systems. It is recognised that it would be beneficial to draw this work together within a single plan in order to have a coordinated approach to finding solutions to the wind turbine – radar issue. Therefore, together with stakeholders in the aviation and wind development sectors, BERR has developed an Aviation Plan to move this work forward so that wind farms can be developed while, at the same time ensuring national security and the continued safe operation of our aviation environment. The structure and principles of the Aviation Plan were endorsed by the Wind Energy, Defence and Civil Aviation Interests Working Group in March 2008.

The overall aim of the Aviation Plan is to provide a suite of generic mitigation solutions to which wind farm developers and their aviation stakeholders can turn when discussing the best potential solutions for any particular wind proposal. The development of this suite of generic solutions will be an on-going process and will build on a number of solutions that are already available to wind farm developers.

The Aviation Plan will provide a tool to identify potential further solutions that offer the most promising prospects for allowing wind turbines and radar systems to co-exist. Importantly, it will allow stakeholders to monitor the progress of programmes of work that will be established to examine the potential of generic solutions and make them technically available. In order to achieve this, the Plan will include information on some key work-streams. These are the key programmes of work being planned and undertaken to find solutions to specific problems that wind turbines currently present to radar systems. For these work-streams, the Plan will present details of the project programmes, costs and the risks to the delivery of mitigation solutions. As such The Aviation Plan is a “living” document that will be updated as progress is made on existing work-streams and new ones are identified and included within the Plan.

The current version of the Aviation Plan presents a summary of the key work-streams that will be the focus of attention over the next months and years. The programmes, costs and risks to delivery of these work-streams still need to be formalised and as these matters are agreed the information will be included within the Aviation Plan.

To ensure the delivery of the Aviation Plan, it will be managed by a senior management board that will be advised by an advisory panel. A separate funding mechanism will also be established to ensure that the work-streams will have appropriate financial support.

The value of the Aviation Plan as a tool for enabling the development of mitigation solutions has been recognised by key stakeholders that have an interest in radar systems and wind farms. To ensure the success of the plan a number of these have signed a Memorandum of Understanding to commit to the full implement the Aviation Plan and its approach to ensuring the timely and effective delivery of solutions to reduce the effect of wind turbines on aviation interests.

SDC Report

The Sustainable Development Commission (SDC): Wind Power in the UK report was launched in May 2005. Full details of their findings on aeronautical & military impacts can be viewed in this report.

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