Technology
How a Senture ADLS decides when the lights go on.
Three questions: how many sensors does the site need, where must aircraft be detected, and what happens when something fails?
01 Planning
Fewer sensors, placed where the terrain allows.
The Senture Optimizer is our in-house planning tool. It combines the turbine layout with a satellite elevation model and searches for the fewest sensor sites that let no aircraft enter the activation zone unseen. Where terrain shadow remains, our coverage maps show it openly.
- Copernicus terrain model and turbine coordinates as input
- Candidates on every hilltop and on a grid across the permitted area
- Viewshed of every candidate at the lower detection limit
- Sensors added only until the barrier is closed
- Coverage maps and elevation profiles ready for the authority
Representative example in real terrain typical of the Norwegian coast, not a real wind farm. Primary radar, activation zone 1,500 m, detection zone 2,500 m beyond it, lower detection limit 100 ft above ground. Elevation data: Copernicus DEM.
02 Sensors
The right sensor mix for the site and the regulator.
| Primary radar | Transponder receiver | Transponder interrogator | Pilot activated lighting | |
|---|---|---|---|---|
| DETECTS | Every aircraft in the detection volume | Aircraft with an active transponder | Aircraft with an active transponder, including their range | Aircraft whose pilot keys the frequency |
| NEEDS ON BOARD | Nothing | Transponder | Transponder | VHF radio |
| TYPICAL ROLE | Main sensor where non-cooperative detection is required | Main sensor where transponders are mandatory | Where transponders are mandatory but existing radars do not interrogate them enough at the site | Additional input for low-level, rescue and ambulance flights |
| HARDWARE | Terma SCANTER 5202, 12 ft or 18 ft antenna | Light:Guard Receiver (LGR), listening only | Transponder interrogator (SSR), installed within the wind farm at a location with a clear all-round view | ICAO-compliant PALC receiver |
03 Signal flow
How the signals flow.
From sensor to obstruction light in three steps: the sensors report to the QUAD server, it decides, and the light control unit at the wind farm switches the lights through the light controller. Every step is supervised by the next.
Sees every aircraft, with or without transponder.
Listens passively to transponder and ADS-B signals.
Interrogates transponders and measures their range.
Pilots switch the lights on by radio.
Lights switched on by remote command, for example by state authorities.
Brings the inputs of all sensors together and decides for each wind farm: can an aircraft be inside the activation zone? Any doubt counts as yes.
EVERY STATE EXCEPT CLEAR MEANS LIGHTS ON
Runs in the data centre of the Light:Guard Group and serves all connected wind farms.
Receives the state of its wind farm and translates it into commands for the light controller.
The turbine side, connected via the manufacturer interface, for example Modbus TCP or OPC UA.
Visible red light: switched by the ADLS. Infrared light: always on, not controlled.
If a stage hears nothing from the one before it, the lights go on.
1QUAD server watches every sensor
2Light control unit watches the QUAD server
3Light controller watches the light control unit
04 Fail-safe
An ADLS never switches lights off. It holds them off.
Lights are suppressed only while every condition is met. A sensor fault, a network loss or a power failure releases the suppression, and the lights return to normal operation.
Are all sensors and links healthy?
NO: LIGHTS ON
YES
Is the activation zone free of aircraft?
NO: LIGHTS ON
YES
No request for light from a pilot or by remote command?
NO: LIGHTS ON
YES
Suppress lights, check again continuously
05 Detection zones
The authority defines the airspace. We document that it is covered.
Light activation zone
The horizontal area around the wind farm. When an aircraft enters it, the lights switch on in good time.
Lower detection limit
The lowest height at which detection is required, either a fixed height above ground or derived from the minimum safe altitude. It drives mast height and sensor positions.
Detection volume
The airspace the sensors must cover without gaps, shown by line-of-sight analysis and confirmed by flight test.
Upper detection limit
The height above the highest obstacle up to which aircraft must be detected. Higher traffic is clear of the turbines.
06 Reporting
Dark nights you can prove.
Every system component keeps a permanent, encrypted VPN connection to the data centre of the Light:Guard Group. Our operations team supervises it around the clock, and you see your own wind farm live in OWL, our online monitoring platform.
If something goes wrong, an alert goes out immediately. Many faults can be diagnosed and resolved remotely, without waiting for a site visit.
LIVE STATUS
Operating state of every component and of the whole system, live in OWL
24/7 ALERTS
Automatic fault detection and an immediate alert to the operations team, for example by email
REMOTE SERVICE
Troubleshooting, firmware and software updates and configuration changes without a site visit
ADLS REPORTS
Automated reports on lights-off time, detection events and availability for any period you choose: an auditable record for you and the authority
07 Retrofit
New obstruction lights for older turbines.
Many turbines still run hard-wired obstruction lights that often no longer meet current marking requirements. BeaconLink replaces them with a complete retrofit kit, without touching the turbine SCADA.
It is a compliance upgrade in its own right. And when you decide on ADLS later, the lights are already prepared for it.
THREE KITS
BeaconLink HI
Nacelle lights for turbines of 150 m and above
BeaconLink MI
Nacelle lights for turbines below 150 m, red or red and white
BeaconLink LI
Tower lights, added to HI or MI where the rules require them
NO SCADA WORK
Installed alongside the turbine control, not into it. No integration project with the turbine manufacturer.
INFRARED
Infrared output together with the red light, for crews flying with night vision goggles.
SYNCHRONISED
All turbines of the wind farm flash in step, as updated national rules often require.
MONITORED IN OWL
Light status and failure alerts, online in OWL.
Questions
What operators ask us first.
How long does an ADLS project take?
Typically 12 to 18 months from site assessment to approval. The authority review is usually the longest step.
Does it work for existing wind farms?
Yes. We deliver for new builds and retrofit existing turbines. Where the installed obstruction lights are not ADLS-ready, BeaconLink replaces them.
Radar or transponder?
It depends on what the national authority accepts. Radar sees every aircraft. Transponder systems cost less but only see aircraft with an active transponder.
How much of the night do the lights stay off?
It depends on local air traffic. Remote sites reach very high lights-off times, sites near airports far less. We estimate it for your site.