Grounding Boat on the Bottom - Question

[ChrisG2100]

Can you ground you boat in the bottom and have the destoyers not "see" you. This doesn't work in SH3 because the destroyers sonar isn't modeled to lose the sub in the bottom clutter?

Thanks

[donut]

& NO,if you are within depth range of DDs sonar.Prehaps under thermal @ max dive. Bottom clutter dosen't figure.

[seafarer]

I'd imagine that, unless the sea bottom was iron rocks, a big long steel tube would make a pretty stark sonar return relative to a muddy sea floor. Metal objects show up really well in bottom scanning active sonar, in my limited experience with it anyway.

[Sailor Steve]

Originally Posted by seafarer

I'd imagine that, unless the sea bottom was iron rocks, a big long steel tube would make a pretty stark sonar return relative to a muddy sea floor. Metal objects show up really well in bottom scanning active sonar, in my limited experience with it anyway.

S-36 grounded on at least three separate occassions...and it worked every time.
http://en.wikipedia.org/wiki/USS_S-38_(SS-143)
http://www.hazegray.org/danfs/submar/ss143.txt

World War II navies didn't have bottom scanning sonar.

[seafarer]

Originally Posted by Sailor Steve

S-36 grounded on at least three separate occassions...and it worked every time.
http://en.wikipedia.org/wiki/USS_S-38_(SS-143)
http://www.hazegray.org/danfs/submar/ss143.txt

World War II navies didn't have bottom scanning sonar.

Reading those accounts, I'd still say it was largly luck, or perhaps the surface ships were using only narrow beam sonar and just missed her by not being thorough enough. Not that being on the bottom shielded her from sonar, active sonar at least. WWII sub hunters didn't need anything specific to find a target on the bottom (that is they did not need any special type of sonar like side scan). Their active sonar projected it's pulses in all directions (panoramic sonar) or forward and down (narrow beam). The pulse just keeps going until it's attenuated beyond detection. A very soft bottom will absorb much of the sound energy, but that would also likely be potentially disaster to bottom out on as you may not get free again. The bottom can create interferance that might confound sonar from clearly delineating the sub target, but that's iffy too.

Generally, I still do not see it as being a useful technique to escape an active sonar search.

[ChrisG2100]

Just as a note. There isn't much to do when being depth charged. Bottoming out would be nice. I got the idea from Eric Topps book. He used it at least once.

[manucapo]

my experience is that once they already detected you
is better to zig zag at slow speed than to ground
cause it seems that once they detected you and you ground, they just keep
depthcarging your general area (they dont seem to know exactly where you are)

but they will just keep depth charging and you might get lucky,

tho this has never been succesfull for me

[ChrisG2100]

U-Boat captains used it in desparation. It was better then making a hole in the water. Just Hoped ubi would model it.

Thanks