In general, it takes too long to get a military submarine into position. I propose a submarine just small enough to fit into a large cargo aircraft. It would have some really big parachutes on top for a drop from the air. Perhaps an air bladder on the bottom for a cushion too.
edit: okay then, a little one.
edit: ordinance can be dropped separately
edit: so can fuel and batteries-- Voice, Jun 13 2007 A couple of points:
1. Wouldn't an air bladder underneath cause it to flip over? Or are you talking about a monstrous air bladder which, until deflated, would keep the sub out of the water entirely?
2. The largest current cargo aircraft (Russian) can just about move tanks, but a 'full-size' submarine is rather bigger and heavier than a tank, isn't it?-- pertinax, Jun 13 2007 You think the enemy might notice the gigantic splash just off their coast? Still, bun for the image.-- Galbinus_Caeli, Jun 13 2007 [pertinax] You are underestimating airlift capacity a bit. The largest US airlifter, the C-5, can carry not one, but two main battle tanks. Or six helicopters.
The smallest nuclear submarine a quick google search can find is a Russian 'Paltus' class at a displacement of 750 tons. If 3/4 of that is water ballast, then you could stuff one of those into a C-5.
Germany has a Diesel/Electric sub at 520 tons. Again, if much of that is water ballast you could stuff it in.-- Galbinus_Caeli, Jun 13 2007 // full-size submarine just small enough to fit into a large cargo aircraft // - Kind of like saying "a full-size automobile just small enough to fit into a large mailbox"
[Voice] suggests a //military submarine// - the Paltus class (project 1083 - the name is also associated with project 877 [Kilo class] boats, much bigger) at 750 tons carries no armament whatsoever, so would scarcely qualify. Ballasting generally runs to about 20 to 30 percent; modern submarines have a pretty low bouyancy margin when surfaced. Since they use cylindrical hulls, a surfaced hull with a 75% bouyancy margin would immediatly capsize.
Anyway, to summarize: that smallest sub is 1/3 the weight of the smallest "military" sub, and still masses over 4 times the capacity of a C-5.-- lurch, Jun 13 2007 Thank you, [Galbinus_Caeli], I sit corrected.-- pertinax, Jun 14 2007 What about a submarine that flys? =ROCK= Caught your title just right in my ear-mitt-- evilpenguin, Jun 17 2007 I half-baked that too, but no one liked that either :-(-- Voice, Jun 17 2007 The primary purpose of a submarine is to attack by stealth. This capability is pretty much destroyed if delivered by airplane. Thus the huge fleet of nuclear powered missile and attack boats maintained by U.S. taxpayers for the benefit of General Dynamics, Raytheon, etc.
Of course none of that means that this hasn't been baked, at least in prototype form, by the Pentagon or a multitude of defense contractors looking for their next big windfall.-- nuclear hobo, Jun 17 2007 //The primary purpose of a submarine is to attack by stealth. This capability is pretty much destroyed if delivered by airplane.//
First sentence is accurate enough, but that second. . .wow! An enemy might know an airplane is approaching their coast. They might note that the plane take up a particular altitude. It is very unlikely they would know if the plane dropped anything into the water unless it made a second radar signal. Possible, but not real likely given that a drop altitude is bound to be below radar detection levels.
Also, there is no need for the sub to be dropped close enough to the shore to be seen by anyone on shore. in fact, this would be a bad idea because waters that close to shores are usually too shallow for subs to operate safely.
Finally, if the sub is flown from the US over to, say, the Mediterranean, the intelligence systems would have several hours to vector the unit to the least-trafficked sea area nearest to the destination.-- Moonguy, Jun 18 2008 Oooh, I love it when people use "vector" as if it were a verb....-- MaxwellBuchanan, Jun 18 2008 why bother with the parachute... subs are sorta "bomb" shaped already... just dive right in.-- FlyingToaster, Jun 19 2008 random, halfbakery