No standard IFF protocol exists for small drones so C-UAS cannot distinguish friendly from hostile

Military aircraft carry IFF transponders broadcasting encrypted Mode 5 signals, but small tactical drones under 25 kg have no standardized IFF system -- a friendly ISR quadcopter looks identical on radar to an enemy kamikaze drone of the same size. In Ukraine, friendly drone shoot-downs by own forces account for an estimated 10-15% of drone losses. This persists because IFF transponders weigh 200-500g and draw 5-10W, a significant penalty for a drone with 1kg payload capacity. Additionally, NATO has no agreed-upon IFF standard for sub-25kg UAS -- each nation uses different drone models with different telemetry protocols.