When Should Hikers Use Visual Distress Signals Outdoors?

On a foggy night off the coast, the way a horn slices through the haze taught me why ships never rely on just one kind of distress signal. I’ve spent enough hours watching the horizon to see how light and sound behave like two different languages at sea: light travels straight and can be blocked by waves or curvature of the Earth, while sound bounces, bends, and can carry around obstacles in ways light can’t. Because of that, mariners use both to cover as many scenarios as possible — day or night, clear or foggy, close or far. There’s also the human side. Visual signals — handheld flares, rocket parachute flares, SOS in Morse with a signal lamp — are instantly obvious at night and give rescuers a precise direction to head toward. But during heavy fog, strong winds, or when visibility is near zero, a bright flare might never be seen. That’s where sound (ship’s whistle, air horn, or even a recorded distress signal) comes in: it can warn nearby vessels, attract ships that are out of sight, and cut through the sensory confusion that happens in emergencies. Add in the fact that equipment fails and people get injured or separated; redundancy matters. Having both types increases the chance someone will notice and react. On top of physics and human factors, there are practical and regulatory reasons. International maritime practice and safety conventions push for multiple, standardized signals so crews and rescuers share a common vocabulary — whether that’s 'SOS' in Morse, visual rockets, or prolonged blasts on the horn. Technology like EPIRBs and radio provide remote alerts, but they don’t replace the immediate, local warning value of a flare or a whistle: a flare gets people looking, a horn gets people listening, and together they create situational awareness that radios alone can’t always provide. After watching a small rescue where a flare drew attention and repeated horn blasts helped guide a lifeboat in, I truly appreciate how layered those systems are — it’s like having several lifelines working at once, and that makes me a lot calmer heading out on longer trips.

You'd be surprised how ritualized distress signals are once you get into the rules — the sea isn’t forgiving of ambiguity. I’ve spent enough nights watching radios and prepping gear to know that international law and maritime best practice line up tightly: if you’re in danger, use every recognized channel and signal available and authorities and nearby vessels are legally obliged to respond where possible. Legally, the backbone is SOLAS (the Safety of Life at Sea Convention), the GMDSS provisions, the COLREGs (which include the list of recognized visual and sound distress signals), and the SAR Convention (Search and Rescue). Practically this means: make a VHF distress call on Channel 16 saying ‘Mayday’ three times, give your vessel name, position, nature of distress, number of people onboard and any injuries. Use Digital Selective Calling (DSC) to send an automated distress alert if your radio has it. Activate a 406 MHz EPIRB (or a PLB/406 device) — that’s tied into COSPAS-SARSAT satellite rescue, and registration of the beacon is legally required and crucial for quick identification. SARTs (Search and Rescue Transponders) and AIS-SARTs help rescuers home in visually and electronically. COLREG Rule 37 and related guidance lists accepted visual and sound distress signals: continuous sounding of a foghorn, gun shots fired at intervals, flames on the vessel, rockets or shells throwing stars (parachute flares), SOS in Morse code by light, orange smoke signals by day, and red hand-held flares. Many national rules also require recreational boats to carry specified visual distress signals if operating in coastal waters. Importantly, misuse of these signals — knowingly raising a false alarm — is a criminal offence in most jurisdictions and can lead to heavy fines or imprisonment; false alerts waste rescue resources and endanger others. Beyond gear and signals, there’s the legal duty placed on masters and crews: ships are required to assist persons in distress at sea, rendering assistance while considering their own safety, and to notify rescue coordination centers. Practically, this means keeping a constant radio watch where required, keeping EPIRB registrations current, testing equipment responsibly (don’t trigger real alerts), and having a plan to broadcast clear, repeatable information during a Mayday. I always sleep better knowing my EPIRB is registered and my crew can call a proper Mayday — the rules exist because they work, and respecting them matters more than pride out on the water.

Night hiking lights up a different part of my brain — it’s equal parts serene and sharpened focus. My top priority is lighting: a comfortable, reliable headlamp with a neutral white beam around 200–400 lumens is my go-to because it frees my hands and gives a wide beam for trail scanning. I always pack a compact backup flashlight and extra batteries (or a USB-rechargeable secondary light). I keep a small red filter or a headlamp mode that switches to red to preserve night vision and avoid blinding teammates or startling animals. Clothing and footwear matter more at night than people expect. I layer for temperature swings — thin base, insulating mid-layer, and a waterproof shell — plus gloves, a warm hat, and reflective accents so I stay visible to others. Sturdy boots with good tread and optional traction devices (microspikes) if there’s ice are essential. Trekking poles help with footing in low visibility. A basic first-aid kit, a compact emergency blanket, and some warm, high-calorie snacks are always in my pack. For navigation and emergencies I carry a map and compass and treat my phone/GPS as helpful but not infallible: offline maps and a fully charged power bank are critical. I also bring a whistle, a small multi-tool, duct tape patch, and if I’m heading remote, a personal locator beacon or satellite messenger. My habit is to practice using all gadgets at home before a night hike and to keep lights and emergency items in easy-to-reach pockets — that way, I feel prepared and calm under the stars, which is why I keep going back out there.

Rescue work at sea is like watching a well-rehearsed orchestra where each instrument—flare, radio, satellite, radar—has its cue. I love how methodical it is: an EPIRB (emergency position-indicating radio beacon) transmits on 406 MHz to the COSPAS‑SARSAT satellite system and almost instantly tells rescuers who you are if you registered the beacon, and often where you are if the beacon has GPS built in. That initial satellite ping gets routed to a Rescue Coordination Center, which is what then kicks off boats, helicopters, and aircraft. Close-range tools are just as cinematic. A VHF radio distress on channel 16, especially using DSC, sends a digital packet with your MMSI and position if your radio is hooked to GPS. A SART (search-and-rescue transponder) paints your location on rescuers’ radar as a cluster of dots, while AIS-SART will pop up as a target on modern ships. Visual pyrotechnics—parachute flares, orange smoke, signal mirrors—and sound signals like continuous horn blasts still matter, especially when electronic fixes are ambiguous. I’ve stood on deck watching a red parachute flare and felt the absolute clarity of being seen; it never fails to give me goosebumps and huge respect for how these systems all slot together.

I’ve heard this idea pop up in thrillers and crime dramas, where characters blink twice to signal they’re in trouble without alerting their captors. It’s a clever trope, but in real life, I’m skeptical. Most official distress signals—like SOS in Morse code or hand signals in aviation—are standardized for clarity. Blinking twice could easily be missed or misinterpreted as a nervous tic or dryness. That said, pop culture loves it because it’s cinematic. Think of 'The Flight Attendant' or 'Gone Girl,' where subtle cues ratchet up tension. If someone tried blinking twice at me, I’d probably ask if they had allergies before realizing they needed help. Still, the concept taps into something universal: the need for covert communication in dangerous situations. Human trafficking awareness campaigns sometimes suggest subtle gestures, like tapping a fist on a car window, but these are widely publicized. Blinking twice hasn’t reached that level of recognition. It’s more of a narrative shorthand—a way to show characters being resourceful under pressure. Fun to watch, but I wouldn’t rely on it in an emergency.

Hiking is one of those activities that feels freeing until you realize how unprepared you can be if things go sideways. I learned this the hard way during a solo trip last year—got caught in unexpected rain, and my phone died because I didn’t pack a waterproof case or portable charger. Now, I always check the weather obsessively and bring extra layers, even if the forecast says sunshine. A basic first-aid kit is non-negotiable, too; I’ve patched up enough blisters and minor cuts to know that much. Navigation is another biggie. Trails can look totally different on the way back, especially if you’re tired. I rely on offline maps (apps like Gaia GPS) and a physical compass as backup. Telling someone your route and expected return time sounds like overkill, but it’s saved hikers who’ve gotten lost. Oh, and snacks! Low blood sugar turns small stumbles into disasters. Jerky, nuts, and electrolyte tabs live permanently in my pack now.

Salt and radio static have a way of teaching you how tiny protocol can feel in the face of panic. When I write scenes with distress signals I try to make the moment sensory first: the whine of a failing generator, a flare’s sulfurous smell, the metallic taste of adrenaline. Practically speaking, a believable distress scene hinges on a few clear elements — the method of signaling, the environment that affects it, and the human mistakes or ingenuity that follow. Start with the signal itself. Use specific, recognizable tools: a VHF radio call on Channel 16, someone shouting 'MAYDAY' three times and then giving position and vessel name; an Emergency Position-Indicating Radio Beacon (EPIRB) beeping on 406 MHz; a handheld flare arc painting the sky; a reflective mirror flash cutting across a sunlit sea; smoke of a ground signal during daytime. The phrasing for radio calls matters — structure the transmission to include the distress word repeated, the vessel/individual, the nature of distress, the position (lat/long or bearings), and any immediate danger or injuries. Dropping in the term 'PAN-PAN' for urgent but not life-threatening situations can add depth and realism. Environment kills or saves a signal. Describe wind pushing smoke sideways until it's useless, rain soaking a flare’s fuse, tall buildings scrambling GPS signals, or a satellite pass being minutes away — that delay is gold for tension. People also mis-handle gear: a soaked battery, a radio left on the wrong band, a transmitter activated without an ID — those tiny errors make a callout feel human. Conversely, improvisation can be great drama: a character fashioning a mirror from broken glass to catch sunlight, Morse code tapped on a pipe, or a makeshift flag visible from the air. If you borrow from fiction, think of 'The Martian' and its inventive long-game signals and 'Cast Away' for the lone survivor’s low-tech ingenuity. Finally, pace the reveal. Don’t dump an exposition-heavy manual; show the countdown — the frantic attempts, the single successful flare, the relief or bitter irony of a missed pass. Consult real references for the technical bits so you can bend them believably without inventing impossible tech. When a rescue call is nailed, it shifts the reader’s emotional register — that’s when I let myself linger on the small human details: a shaky voice, a hand over a radio, the quiet after a repeated 'Mayday' — those are the beats that stick with me.