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Barkerov · 09-15-15, 07:47 PM

I think I am not writing enough words and therefore coming across as an idiot who knows nothing about bombing, fuses etc. Let me start by saying that I know a lot more about aircraft than submarines and that flight sims were my first love of war simulation games. I agree totally that the way the game implements aircraft is unrealistic, the reason you supplied of giving the player a chance is probably spot on, since developers have to cater for the realists and the arcade players equally in order to maximise profit.

I don't think for one second they got closer than the fragmentation envelope of the bomb they were employing. I also am under no illusion that the bomb will fail to detonate after impact with the water becasue of damage to the bomb. After all they are designed to hit the ground at supersonic speeds. Furthermore I am not stupid enough to believe that Mythbusters provide anything more than proof of concept experiments. Your point about increasing projectile surface area / weight being confounded by muzzle velocity is correct. However the key concept, that high velocity impact with the water dramatically changes the projectiles behavior, is valid.

My query revolves around how deep is deep enough both IRL and in the game. I have not seen aircraft bombs with delay fuses yet so the first question is how damaging would a surface detonation be to a submarine at various depths. I suspect not much at periscope depth

The second question, which you got me thinking about, was how deep will a bomb penetrate underwater before detonation. Lets for a second assume that skipping of the bomb is a non issue. My feeling (please note how I distinguish between what I think by using emotive terms and what I can prove as fact) is that the bomb will lose almost all of its airborne energy upon impact with the water greatly reducing the speed at which it travels underwater particularly in the direction of depth. To get to 40ft with a 0.1 second fuse it is easy to see that it has to travel downward at 400ft per second, a value which I find very hard to believe. A half second fuse which you suggested would detonate at 225-375 feet deep would require downward motion equal to the impact velocity. This would defy the laws of physics.

I found a book today entitled "Britain's Anit-submarine Capability 1919-1939" which stated that one report concluded that "for entry velocities of more than 250fps the trajectory curvature may be so great that accurate bombing of submarines at depths greater than 50ft would be impossible". I have probably taken this quote too far out of context but there must be a reason why planes carried depth charges instead of bombs.

09-15-15, 07:47 PM	#352
Barkerov Soundman Join Date: Aug 2015 Location: Australia Posts: 147 Downloads: 42 Uploads: 0	I think I am not writing enough words and therefore coming across as an idiot who knows nothing about bombing, fuses etc. Let me start by saying that I know a lot more about aircraft than submarines and that flight sims were my first love of war simulation games. I agree totally that the way the game implements aircraft is unrealistic, the reason you supplied of giving the player a chance is probably spot on, since developers have to cater for the realists and the arcade players equally in order to maximise profit. I don't think for one second they got closer than the fragmentation envelope of the bomb they were employing. I also am under no illusion that the bomb will fail to detonate after impact with the water becasue of damage to the bomb. After all they are designed to hit the ground at supersonic speeds. Furthermore I am not stupid enough to believe that Mythbusters provide anything more than proof of concept experiments. Your point about increasing projectile surface area / weight being confounded by muzzle velocity is correct. However the key concept, that high velocity impact with the water dramatically changes the projectiles behavior, is valid. My query revolves around how deep is deep enough both IRL and in the game. I have not seen aircraft bombs with delay fuses yet so the first question is how damaging would a surface detonation be to a submarine at various depths. I suspect not much at periscope depth The second question, which you got me thinking about, was how deep will a bomb penetrate underwater before detonation. Lets for a second assume that skipping of the bomb is a non issue. My feeling (please note how I distinguish between what I think by using emotive terms and what I can prove as fact) is that the bomb will lose almost all of its airborne energy upon impact with the water greatly reducing the speed at which it travels underwater particularly in the direction of depth. To get to 40ft with a 0.1 second fuse it is easy to see that it has to travel downward at 400ft per second, a value which I find very hard to believe. A half second fuse which you suggested would detonate at 225-375 feet deep would require downward motion equal to the impact velocity. This would defy the laws of physics. I found a book today entitled "Britain's Anit-submarine Capability 1919-1939" which stated that one report concluded that "for entry velocities of more than 250fps the trajectory curvature may be so great that accurate bombing of submarines at depths greater than 50ft would be impossible". I have probably taken this quote too far out of context but there must be a reason why planes carried depth charges instead of bombs.