LIRT LED Inset Threshold and Wing-bar Light

The LIRT is a 12-inch inset LED light that covers two spatially distinct but functionally related roles: the runway threshold lights that mark the beginning of the landing area, and the threshold wing-bar lights that extend the green threshold indication laterally beyond the runway edge to give pilots a wider field-of-view reference on final approach, particularly in fog or when breaking out of cloud on a wide-body approach.

Threshold lights are emitted green in the landing direction and red in the opposite direction (serving as runway-end lights for aircraft on the opposing threshold), making bidirectional optical performance a requirement embedded into the certification standard. The LIRT achieves this in a single flush-mounted inset fitting, avoiding the alternative approach of separate threshold and runway-end fixture types.

The wing-bar function increases the power draw significantly — 73 VA for the combined threshold-plus-wing-bar configuration versus 36 VA for threshold-only — because wing-bar arrays are driven at higher intensity to reach pilots on wide approach paths. Both configurations fall within the load margins of standard 6.6A series circuits.

At 12 inches the LIRT shares a can-size with the LIRE runway edge light, meaning airports running a standardised 12-inch inset infrastructure need only one excavation template for multiple fixture types. Electronics are built to resist the shock and vibration environment of a high-traffic threshold region. Fault monitoring and Arctic Kit heating are available as options, supporting CAT III operational viability at both equatorial and high-latitude airports.