TL421 Halogen Elevated High-Intensity Directional Light

The TL421 is a 6.6 A series-circuit halogen elevated directional light built for the most demanding segments of an approach and runway lighting system — approach centreline bars, approach side rows, threshold, threshold wing bar, and runway end. The fixture accepts a PK30d airport bulb and delivers between 65 W (runway end) and 200 W (threshold wing bar) of arc-tested halogen intensity, ensuring precise photometric compliance with ICAO Annex 14 Appendix 2 tables and EASA CS ADR-DSN requirements across all three instrument categories.

At 2.3 kg and 214 × 292 × 179 mm, the TL421 is dimensionally matched to standard frangible couplings and breakaway mounting systems. Horizontal adjustment spans 0–360° and vertical adjustment spans −10 to +14°, enabling precise optical alignment on complex approach geometries without cutting new foundations. The IP67 rating and a tested wind resistance of up to 480 km/h provide a robust margin above real-world cyclonic and shamal wind conditions encountered in Gulf-region operations.

The TL421 occupies a specific role in Transcon's product range: it is the high-intensity workhorse for airports that maintain halogen-based approach systems or that are upgrading segment by segment, retaining existing series circuit regulators. Procurement engineers evaluating a like-for-like fixture replacement — or equipping a new runway designed to a CAT II/III standard — will find the TL421 directly aligned to the photometric tables without the driver-electronics overhead of the LED equivalent. Operating temperature tolerance of −50 to +55 °C makes it equally viable at high-altitude Central Asian aerodromes and in the high-ambient-temperature ramp environments typical of GCC airports.