LIRD LED Inset Touchdown Zone Light

The LIRD is a unidirectional 8-inch inset LED fixture that forms the touchdown zone lighting (TDZL) array on precision-approach runways. Touchdown zone lights are a mandatory requirement under ICAO Annex 14 and FAA AC 150/5300-13 for CAT II and III operations, providing pilots with the lateral-extent and approach-angle reference they need during the final metres of a low-visibility approach when the runway centreline is the primary guidance cue.

Mounted flush with the pavement in the first 900 m from threshold on each side of the centreline, TDZL arrays must survive tens of thousands of main-gear overruns per year without degradation. The LIRD's drop-forged dome and cast-aluminium lower cover are specifically chosen for this load path, and the 6.35 mm overhang minimises tyre-strike forces that would shorten fixture life on a busy CAT III runway.

At 16 VA unidirectional the LIRD is substantially more energy-efficient than its halogen predecessor, directly reducing operating costs on arrays that may comprise 60 to 120 fixtures per runway. Variable intensity (five CCR steps per standard) means the same fixture produces FAA-compliant output at both maximum and minimum CCR current settings, preserving compatibility with existing series-circuit infrastructure during phased LED conversion programmes.

The optional Arctic Kit adds thermostatically controlled lens heating — essential for northern European, Canadian, and high-altitude airports where ice formation on optical surfaces would interrupt the continuous visibility requirement of CAT III certification. A monitoring module enables individual fixture-level fault detection, supporting the very low maximum-unserviceability thresholds that CAT III approval demands.