Science.....

Is it possible and what would it take to travel supersonic submerged? Just thought that I'd pick your wee brain cells!

Hmm, I doubt it, in water sound travels with a speed of around 1500 m/s, compared to around 330 m/s in air. The hig speed combined with the the enormous density of water vs. Air, the amount of friction will be sky high.

Tricky one
the sonic boom (through air) is created by the compression of air in the wake of the aeroplane creating it, compressing the gaseous state of the atmosphere to near-liquifaction.

Water, unfortunately, doesn't compress; the wake of a hydroplane attempting mach speed could be quite damaging or even dangerous to shore-based life or surface vessels.

As for actually accomplishing it regardless of collateral damage, I don't think it would be a problem from a hydrodynamics point of view but I've no idea how much energy would be required from a powerplant(s) to overcome water as a medium to mach speeds. This factor would increase far more radically with depth than altitude would for an aeroplane.

If u could create a vacumn in which the vehicle would travel, sort of like a bubble surrounding the craft, friction would be irrelevant...

Maybe use sonic waves to create a bow wave infront of it, parting the water in front of the craft???

lesofprimus said:

If u could create a vacumn in which the vehicle would travel, sort of like a bubble surrounding the craft, friction would be irrelevant...

Maybe use sonic waves to create a bow wave infront of it, parting the water in front of the craft???

Click to expand...

Like a warp envelope?
The bubble would have to move, too, so you'll still get friction.
Another interesting philosophical point here is, if the craft would be in vacuum, wouldn't it be always faster than sound, since the speed of sound is 0 or non-existant in vacuum?

Les is thinking in the right direction. Supersonic submersibles are not only theoretically possible, but also likely to be technically achievable in the not-to-distant future.

Here's a link that gives an outline of the general theory and principles involved:

Supersonic Underwater Vehicle?

JL