Am I completely off-base in thinking almost everything about a submersible drone is a better idea? No radar signature, much bigger haulage, can idle in location for much longer when needed, and presumably supports somewhat surreptitious unloading at sea if needed?
The Straits of Gibraltar has a strong net inflow current, which might make drone submersibles a bit prone to getting lost.
Also, the prior art for smuggling across the straits were fast launches which would bump upon to beaches and be quickly disgorged. This means that the Guardia Civil take a lot of interest in what happens along the coast.
Also, let it be said that the coast up East from Gibraltar is very much not as empty as it is from Algeciras Westwards, with a lot of development on the Costa del Sol. Makes it hard to have slower than launches/ribs submarines do their thing.
> The Straits of Gibraltar has a strong net inflow current
Just a fun fact, I heard that during WWII most of the U-boats that made it through the Strait of Gibraltar never made it out. A combination of being sunk and not having powerful enough engines to make it back out.
From a documentary I watched something like this is one of the preferred techniques for the Colombian cartels now. It's called the torpedo technique.
They design torpedo style units that get towed behind a fishing boat or such. At a desired location they detach it, and it just loiters below the surface. At some pre-arranged time it pops up to the surface and activates a radio beacon, so that a pickup ship can snag it.
It's less complicated than building an autonomous AUV, and far less likely to be spotted by arial surveillance than a narcosub. Lower capacity but still very lucrative I imagine. And very nearly risk free.
These narco-submersibles have a much higher entry cost, apparently. And you'd probably need something a few meters long, just to house the motor necessary to fight the currents.
The drone was apparently off the shelves. And the police didn't say if they ever actually got it into the air at all.
The sea is flat and you can see a long way. Radar can see a long way. These people could choose a landing spot in a hilly area with few people and many roads, where few people could see the drone land and they could unload, drive off and mingle with traffic after only a few minutes' driving.
Maybe the drone could even finish charging unattended and take off to fly back to Morocco.
It is extremely likely that the Spanish Navy or Intelligence Agency has an whole array of underwater listening devices, due to the Strait of Gibraltar.
So if you're coming from Morocco with a homemade sub (probably woefully unoptimized for being quiet), I'm gonna assume that those listening will pick up your signature.
The main downsides will be that it has much more drag to fight against and also if you're actually underwater you can't just use GPS like you can in the air making navigation much harder.
