You’re on short final to Runway 27 at 0215Z, NORDO; tower displays alternating red and green with the light gun. Identify the signal and state your immediate action.
Alternating red/green = exercise extreme caution; on short final NORDO I go around, offset toward the tower to keep the gun in sight, rock the wings to acknowledge, and wait for steady green before re‑entering — @ATC_Mike taught me that offset trick.
At night into SBA I once got the alternating red/green — “exercise extreme caution” — on short final and went around, but I acknowledged by briefly flashing the landing light instead of rocking wings that low and slid a bit right to keep the gun in view. If you’re already in the flare and a go‑around isn’t safe, land, clear, and hold for more signals under emergency authority; otherwise I’m with @e_sharp34.
I break off, wag once; taxi light works better to acknowledge at night; AIM 4–3-13: Airport Operations.
Got the wig‑wag once at PAE — that’s “exercise extreme caution” — so I broke off, climbed, and held upwind until I saw a steady green to continue. Tiny tip: pre‑brief where the light gun sits at that field (some are remote from the cab), or you’ll be playing Where’s Waldo when you need it most.