An Instrument Landing System (ILS) is a highly accurate radio signal navigation aid consisting of two antennas which transmit signals to receivers in the aircraft cockpit—a glide path tower located next to the runway at the northern end and a localiser antenna at the southern end. These antennas provide the pilot with vertical and horizontal guidance when landing in low visibility. An ILS is not used by departing aircraft.
How will an ILS improve flight reliability?
Gold Coast Airport is operating safely without an ILS and the public can continue to travel by air with confidence. An ILS enables airlines and airports to continue operations in low visibility conditions, such as rain and low cloud. This will increase the reliability of landing at the airport. In any weather conditions, pilots must be able to see the runway before landing.
Installing an ILS at Gold Coast Airport will reduce the “decision altitude” or height at which a pilot must make the decision to continue with the landing with the runway in sight or to go-around or divert because the runway is obscured by cloud. An ILS will reduce the decision height, or minima, from 430 feet to 280 feet, improving the chance of landing in poor weather. However, an ILS will not guarantee a landing in all weather—the decision to land in poor weather is ultimately up to the pilot-in-command.
What is the difference between ILS and Smart Tracking?
Smart Tracking is satellite-assisted navigation technology allowing aircraft to fly with greater accuracy and can assist in allowing an aircraft to land in low visibility conditions.
At the Gold Coast, Smart Tracking allows aircraft to approach Runway 14 from the south and north with the majority of the flight path over the water before making a final approach for landing. Smart Tracking at Gold Coast Airport has a decision altitude or minima—where the pilot must be able to see the runway to continue with the landing—of 430 feet.
In comparison, an ILS provides a minimum decision altitude of 280 feet and improves the predictability of landing in low visibility conditions.