Windfarm Lighting Strategy Paper 30 December 2020 CL-5522-RPT-002 V1.0 www.cyrrus.co.uk [email protected] Windfarm Lighting Strategy Paper Executive Summary Windfarms comprised of turbines with maximum tip heights of 150m or more AGL are considered en- route obstacles and thus must be appropriately notified to aircraft flying at night. Consequently, such windfarms must be lit so that pilots can see and avoid them. The UK requirements for lighting windfarms derive from standards set by the International Civil Aviation Organisation (ICAO). Individual wind turbines are fitted with red obstruction lights which are illuminated in the hours of darkness regardless of whether aircraft are in the vicinity or not. For large windfarms this gives rise to concerns from community and other stakeholders regarding landscape and visual impacts, including effects to dark landscapes. This can result in delays and difficulties in securing permissions for windfarm development and development of bespoke lighting solutions. This Paper considers whether there are alternative systems that can be employed to meet regulatory requirements and provide for safe navigation with common standards for obstruction lighting of windfarms. It reviews existing ICAO requirements, how these are implemented by the UK, and concludes that the UK CAA could amend its existing rules to reduce environmental impacts while remaining entirely aligned with ICAO. In consideration of available options, it is considered that development of an Aircraft Detection Lighting System (ADLS) dependent upon Electronic Conspicuity (EC) has the greatest potential to resolve the challenges identified. Further consideration is made to the climatic conditions in the Western Scotland region and to what level Visual Flight Rules (VFR) are permissible. In conditions where VFR is not permitted the consideration must be made as to the requirement of having lit wind turbines. Coupled with the technical solutions available, there is a reasonable solution to minimise light pollution when no VFR flying is possible. Using an EC ADLS system, visible lighting would only be triggered as a warning to EC transmitting aircraft that have entered a safety buffer (box) and would only remain illuminated for the required amount of time. Adoption of an EC ADLS requires the correct equipment to be installed within aircraft and ultimately mandatory EC carriage at night. The Paper draws on the results of a stakeholder consultation exercise to understand the take-up of EC systems, and proposes a route forward for further stakeholder engagement between industry, the CAA and aviation users. CL-5522-RPT-002 V1.0 Cyrrus Limited 2 of 60 Windfarm Lighting Strategy Paper Abbreviations ADLS Aircraft Detection Lighting System ADS-B Automatic Dependant Surveillance-Broadcast AGL Above Ground Level ANO Air Navigation Order ASU Air Support Unit CAA Civil Aviation Authority CAT Commercial Air Transport cd candela CTA Control Area CTR Control Zone DfT Department for Transport EC Electronic Conspicuity GA General Aviation GNSS Global Navigation Surveillance Systems HEMS Helicopter Emergency Medical Service ICAO International Civil Aviation Organisation IFR Instrument Flight Rules IR Infra-Red LFA Low Flying Area MCA Maritime Coastguard Agency MCSO Mission Critical Services Onshore MET Meteorology MOD Ministry of Defence MSA Minimum Safety Altitude MSD Minimum Separation Distance MSL Mean Sea Level NATMAC National Air Traffic Management Advisory Committee NVD Night Vision Device OSA Offshore Safety Area PSR Primary Surveillance Radar SERA Standardised European Rules of the Air SPR ScottishPower Renewables SSR Secondary Surveillance Radar CL-5522-RPT-002 V1.0 Cyrrus Limited 3 of 60 Windfarm Lighting Strategy Paper TMA Terminal Manoeuvring Area TTA Tactical Training Area UAS Unmanned Aerial Systems VFR Visual Flight Rules VMC Visual Metrological Conditions CL-5522-RPT-002 V1.0 Cyrrus Limited 4 of 60 Windfarm Lighting Strategy Paper Contents EXECUTIVE SUMMARY .......................................................................................................... 2 ABBREVIATIONS ................................................................................................................... 3 CONTENTS ............................................................................................................................ 5 1. INTRODUCTION ....................................................................................................... 8 1.1. Purpose ......................................................................................................................................... 8 1.2. Background ................................................................................................................................... 8 1.3. Statement of Need ........................................................................................................................ 9 1.4. Structure of the Paper ................................................................................................................10 2. EXISTING REGULATIONS ........................................................................................ 11 2.1. ICAO ............................................................................................................................................11 2.2. UK CAA ........................................................................................................................................12 2.3. Aeronautical Studies ...................................................................................................................14 2.4. Aviation Detection Lighting Systems ..........................................................................................14 3. EXAMINATION OF THE RATIONALE FOR WIND TURBINE LIGHTING ......................... 16 3.1. Introduction ................................................................................................................................16 3.2. Airspace .......................................................................................................................................16 3.3. General Aviation .........................................................................................................................16 3.4. Ministry of Defence (MOD) .........................................................................................................17 3.5. Emergency Services and Government Agencies .........................................................................18 3.6. Survey Aircraft (Pipeline inspections etc.) ..................................................................................19 3.7. Flight Conditions and VFR at Night .............................................................................................19 3.8. Climate – Western Scotland ........................................................................................................20 3.9. Exceptions to VFR at Night Rules ................................................................................................21 3.10. Airspace Usage Summary ............................................................................................................22 4. POSSIBLE SOLUTIONS ............................................................................................ 23 4.1. General ........................................................................................................................................23 4.2. Dimming ......................................................................................................................................23 4.3. Shielding and directional intensity ..............................................................................................23 4.4. Unlit Tall Obstacle Zones .............................................................................................................25 4.5. Bespoke Aeronautical Studies .....................................................................................................25 4.6. Cardinal and Perimeter Lighting .................................................................................................25 4.7. Reduced Lighting .........................................................................................................................26 4.8. Compulsory Night Vision Goggles Zone – Infra-Red Lighting Only .............................................26 4.9. Aircraft Detection Lighting Systems (ADLS) ................................................................................26 CL-5522-RPT-002 V1.0 Cyrrus Limited 5 of 60 Windfarm Lighting Strategy Paper 4.10. Primary Surveillance Radar ADLS ................................................................................................27 4.11. EC / Transponder Activated ADLS ...............................................................................................28 5. ENGAGEMENT ACTIVITY AND RESULTS .................................................................. 31 5.1. Stakeholder Engagement ............................................................................................................31 5.2. Purpose .......................................................................................................................................31 5.3. Who responded? .........................................................................................................................31 5.4. Results .........................................................................................................................................31