Depth charges.
The weapon described is a depth charge.
Airplanes dropped depth charges and specialised torpedoes
Most pleasure submarines are either personal watercraft with limited diving capability, or tourist submarines with limited depth capability.
No, submarine crews do not generally feel waves when operating submerged. During "normal" undersea operations, submarines are almost always below a depth that would cause them to react to wave action.
Define "submarine" and "bottom of the sea".Submarines are designed for a particular pressure/depth. The designers also incorporate a margin of error, so the actual depth at which the submarine would be crushed by external pressure ("crush depth") is generally marginally greater than its "design depth". Submarines normally operate at a fraction of their design depth (this is called "test depth") under normal peacetime conditions. Different navies use different fractions as the test depth; the German navy specifies a test depth of half the design depth, while the US navy uses 2/3 of design depth.If the sea floor depth at a particular point is less than the sub's test depth, then they can approach it (though, for various reasons, actually touching it is nearly always a bad idea).The deepest known point in the ocean is the Challenger Deep in the Marianas Trench, at about 10,916 meters. Two human-manned vessels (one solo craft and one with two occupants) have gotten within a few meters of the bottom there, but both of them were technically "submersibles" rather than "submarines"; they had limited mobility and basically existed to go primarily straight down (and, hopefully, back up) rather than cruise for long distances horizontally. Actual submarines generally have much lower design depths. For example Virginia-class US nuclear attack submarines have a test depth of only about 240 meters (putting their design depth at about 360 meters).
Yes sonar can be used at periscope depth. Surface ships also have sonar arrays on them. They are usually used to detect submarines.
The military submarines maintain depth by use of the planes. As they move through the water, a little up or down "tilt" on the planes will keep the boat at the correct depth.
Because thin metals will crush under extreme depth
U.S. Submarines can dive 800-plus feet. (Official depth; however, can dive deeper. The US Navy itself acknowledges that most of it's attack submarines can operate down to at least 985 feet, and many to over 1400 feet.
It's about 2.5 miles below the surface of the North Atlantic. That depth is far beyond where a diver can go, but specialized deep-sea submarines can visit the wreck site.
It depends on the submarine. If measure the distance from the top a fully extended periscope to the bottom of the boat you will get the "Depth of the Keel" at which the periscope is out of the water. Generally between 30 feet and 70 feet.