old forts used earthworks, can ships use water walls for defence

[mainsworthy]

old forts used earthworks, can ships use water walls for defence? if a ship could lower its self deeper or put up water barriers , I was just wondering thats all

[ernieschwitz]

Well the idea is interesting. Water does have an effect on projectiles, slowing them down and changing their trajectory.

[Curtis Lemay]

Submarines are entirely under water yet subject to torpedos and depth charges.

[RangerJoe]

Water is hard, there would be pressure waves that can do more damage than the actual explosion if there is no water. Plus by going lower into the water, that makes the ship more likely to sink beneath the waves without coming back up when it is desired.

[Platoonist]

It is much better for bombs or shells to explode near a target and under water. Damage is primarily from hydraulic effect through the surrounding fluid. Fluids are in-compressible. Therefore, more energy is delivered to the target than an explosion in air, which is very compressible and dissipates much more energy.

It is the same reason depth charges are so effective. A near miss is almost as deadly as a direct hit. Plus, the powerful shock waves from those near misses do nasty things to vulnerable ship systems like rudders, shafts, seals and hydraulics. Many a submarine was tracked to its eventual destruction by the knocking sound coming from a bent propeller shaft or blade.

[czert2]

old forts used earthworks, can ships use water walls for defence? if a ship could lower its self deeper or put up water barriers , I was just wondering thats all

you mean like something when ship is sinking and then sunk ?

[Matt R]

Refer to USS Monitor.

[mainsworthy]

it would be very cost effective, just bags hung on sides

[mainsworthy]

what about ICE

what im getting at, is water is the most abundant to shipsm even tanks put sandbags on

[Platoonist]

what about ICE

You might want to read up about the proposals to make a frozen ice composite material called Pykrete in WW2.

https://en.m.wikipedia.org/wiki/Pykrete

Ultimately, Pykrete was a failure. It was certainly strong, but it had to be kept cool. While it took longer to melt than pure ice, it did still melt, and the cost of building a refrigeration plant to preserve the material was staggering as it was heavy and had to be kept very cool to keep it from sagging. The Mythbusters program tried building a boat from the stuff and it didn't last too long.

[RangerJoe]

Relatively speaking, water is hard and not compressible. You want something with an air gap between steel plates. Besides the cooling problem, ice fractures easily.

[Platoonist]

it would be very cost effective, just bags hung on sides

The problem with any sort of ship armor nowadays is that the benefits don't justify the weight and the cost anymore. That's why no one builds battleships anymore. Moreover, you can't put super-thick armor everywhere so in past practice it was usually concentrated around the waterline and reduced everywhere else. That made sense when the primary threat was optically sighted gun fire from other ships at visual range. It doesn't make sense against a supersonic missile that can pick its trajectory in flight and plunge straight down through the ship's deck while your ice bags hang uselessly from the sides.

[mainsworthy]

I was thinking temp armor when needed

[RangerJoe]

I suppose that water coming from a high pressure hose like a fire fighting hose would stop some of these small aerial drones. But the water would have to hit the drone to knock it down and there are better ways to eliminate them.

[mainsworthy]

what about ice bullets

[mainsworthy]

i think its so cheap for ships to get water, it should be considered. it just makes sense to me. a missile detonates on impact and if it impacts ice before the ship then damage should be less

[RangerJoe]

what about ice bullets

I have thought about that but they have to be kept very cold plus the friction from the air after they have been fired would melt them if they were not shattered when the bullets are fired.

[RangerJoe]

i think its so cheap for ships to get water, it should be considered. it just makes sense to me. a missile detonates on impact and if it impacts ice before the ship then damage should be less

It would depend upon how think the ice is but also the ice will transfer energy to the ship. Then there is the problem of how thick is the ice and how do you keep it intact and frozen.

[ElvisJJonesRambo]

Hologram ships, aka Ghost ships would be fun.
Cast an Armada of vessels across the Air & Sea to trick radar.
Enemy wastes ammo on nothing.

Wonder Woman had the invisible jet, but she was visible.
She can still be spotted.

[Platoonist]

I'm no engineer but I'm fairly certain that the massive thermal and kinetic energy in the forward shockwave of a missile going Mach 1+ would flash any ice shield into a weal of steam in milliseconds.

Plus, spreading tons of ice on a ship's decks would severely compromise it's center of mass and stability. I can't imagine any sane captain wanting to see his ship capsized before battle is even joined. Then there is the nightmare of trying to do damage control on iced-up decks.