I think this begs a little perspective. SAR units don't just go wandering looking for people. SAR costs money. They do it when they train and when they're activated. Not because they're walking their dog and feel like looking for somebody. So let's assume they are aware that there is someone lost and needs findin'.
First let's assume a rescue at sea.. Now, I'm not in the merchant marines, but I'd be hard pressed to believe there are a pair of NOD's on the bridge of every tanker, trawler, and cargo vessel. So at sea that limits assets with NV capabilities to essentially Coast Guard helicopters and search aircraft. So IR would work great for them, but you might get passed by a dozen ships that can't see your beacon because it's not visible. Alternatively, if a shrimp boat sees a blinking light, especially when there's nothing around and they've been told there's a man overboard, they're gonna check it out. If the coasties are out looking for someone they know is lost, at night, with goggles on, they are certainly going to investigate every beacon they see.
Let's move to land. Most land-based SAR groups are volunteers of some capacity, supplementing whatever official assets are in place. Most private citizens aren't going to be carrying around I2 devices of any sort, and most agencies aren't going to be using them unless they've received surplus 1033'd from the government. But for the sake of argument let's assume that everyone has them. Visible beacons are just as visible under NOD's as IR beacons. The idea that they are actively out looking for someone and would ignore a beacon because it's not IR is pretty reprehensible. I would raise hell if someone I loved got lost and someone said, "eh, we didn't check it out because it wasn't IR flashy only." Someone would be in the hospital and I would be in jail.
But a more realistic scenario is that you've got 50 people out in the woods, without thermal or night vision capabilities whatsoever, and it doesn't matter how flashy for how long your IR beacon is, they're never gonna find you.
Do IR beacons have their place? Absolutely. I would never dream of hunting at night under NOD's without IR beacons on everybody. Would I ever actively choose to carry an IR beacon
OVER a visible spectrum beacon in the event I might need it to signal rescuers? Not on my life, because that's literally what's at risk. If you want to supplement, have at it, but unless you're sneaking around waiting for a PJ to pick you up, there's no good reason to choose IR over visible. And if some local SAR dude told you that they'd investigate an IR beacon but not a visible beacon I'd run that all the way up that chain as far as it goes because that's unacceptable.
@fsardone you did a really nice job of covering why lasers aren't the best choice, but please stop with the "
OMGLASERSWILLBURNTHEPILOTSEYEBALLSOUTANDALLTHEPLANESWILLCRASH" hyperbole. While hyperbole at best, it's fear mongering at worst. Like you mentioned, they're used as a deterrent in restricted airspace. You know why? Because they are safe way of GETTING SOMEONE'S ATTENTION. What do you think would happen if the US government blinded some granny pilot who screwed up and ended up in restricted airspace, and she crashed her little rental 172 into a school full of kids.
We can have an adult discussion about the pros and (several) cons of relying on a laser as opposed to dye, signal mirror, PLB/PAB, visible light, etc., but let's leave the reality tv level drama out of it. I know pilots who were actually blinded by lasers, they were A-10 guys when the aircraft was first getting rated for NOD's use back in the early 90's and they had eyeball damage from their high power IR finger lasers when roping targets during FAC sorties. Turns out nobody thought of specular reflections from the canopy glass entering behind a set of ANVIS goggles. They used to have purple visors too, because they thought that the Iraqi's were gonna shoot lasers at the aircraft and blind the pilots. I know because there's one sitting in a helmet bag in the garage.
A bunch of us lost a friend, and if he had any one of several signaling devices, he might have been found, waterlogged and dehydrated, but alive.
We owe it to him to be honest and realistic.
