a new kind of signal flare

With drone technology improving exponentially, and with LED technology emitting ever more piercing light, I think it's time to think about how these two technologies can be combined into something awesome: a hovering signal flare.

My concept is simple. The original signal flare is something normally shot from a pistol. Well, the drone flare would initially operate on the same principle: imagine a tiny little robot drone tucked into a cylinder that sits inside the barrel of a flare gun. You're in the middle of the ocean, stranded after a plane crash; you point the gun into the air, fire the flare, and the drone cylinder shoots out with traditional propellant. As the drone rockets into the sky, it deploys into its quadcopter form, hovering 300 to 600 feet over your head for as long as its battery will allow—all the while emitting piercing bursts of LED light, possibly even in a Morse pattern that says "SOS" or that broadcasts GPS coordinates. AI software inside the drone allows it to remain steady even in high wind, and the drone can judge whether to rise or descend depending on wind conditions.

And speaking of GPS: the drone would come equipped with that, too: a strong link between the drone and an emitter inside the flare gun's handle would keep the drone floating over your head, no matter where the ocean currents might take you. And the drone wouldn't merely be Morse-ing out your GPS coordinates: it'd be broadcasting them in a several-miles-wide radius to any ships that might be nearby.

If the drone receives an acknowledgment signal from some nearby ship that is willing to change course and rescue you, the drone will steadily descend as the rescue vessel approaches, thus ensuring that the vessel comes right to your exact location.

For this idea to work well, several things need to happen:

1. The drone needs to be able to stay aloft for a much, much longer time than a standard flare. A standard flare can be fired up to an altitude of anywhere from 300 feet to 1,000 feet. At about 300 feet, a flare is visible up to 5 miles away. Visibility increases with height. A regular flare starts falling as soon as it's hit its maximum altitude. (source) Presumably, such a flare, even with its tiny little parachute, will remain in the air for only a few minutes. The lower it gets, the less visible its light is.

2. The LEDs on the drone flare would need to be at least as bright as the light emitted by a standard flare.

3. The drone flares that I have in mind would need to be cheap and simple to produce so that, in theory, every single passenger could have one.

4. Vessels would need to carry devices that allow them to receive and respond to a drone flare's signal. This implies something like a network made up of standardized nodes: everybody carrying the same brand or type of equipment so they can pick up signals from the same brand or type of drone flare.

I dunno... I think the concept is sound, at least, but I have no idea how realistic my idea is, given the current state of technology. Tiny quadcopter drones, sold on Amazon, don't stay aloft much longer than a few minutes before they need to be recharged. I'm envisioning a drone flare that stays aloft for an hour or more, in good weather or in bad. How do the energy requirements affect the weight of the drone? Might it be better simply to design a drone flare that, instead of hovering, uses its quadcopter rotors to brake its fall enough so that the drone, instead of plunging, settles to earth in a slow, stately manner?

Something to think about, at least. Not that I'm planning on being stranded in the ocean anytime soon, but... one never knows.


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