skipping 88mm stones

[Keelbuster]

I wonder if shells fired by warships skip off the surface like stones? I imagine they would, and while it would be _pure_ candy, I'd love to see something like that in SH. I can just imagine the fear as a shot that fell short bounced up and past the conning tower, unpredictable like cannon balls bouncing and spinning through lines of 19th century infantrymen.

[Brag]

Never heard of it, but I imagine it is possible. The shape of the shell is not for skipping.

During WWII Americans experimented with a skip bomb. It had had winglets for skipping.

[von stauber]

turns it it is nearly impossible to bomb/damage a dam just by dropping a bomb onto it - so a British enginneer spent his entire war time effort designing a bomb that would be dropped several hundred yards away from the dam, skip on the surface towards the dam, sink when arriving at the dam and then denotate at just the right depth- took years of trial and error to work it all out but he finally got it right and the RAF went wild blowing up germany dams

excerpt from DVD
"In 1943, the war was not going well for the Allies. The Nazis were in firm control of the European coastline and only approachable by air. Engineer Barnes Wallis had a bold (and, many thought, bizarre) idea to turn the war around. His creation--a bouncing bomb--was an innovative blend of simple physics and precision flying with the potential to unleash a torrent of destruction on Nazi industry. MAN, MOMENT, MACHINE details what happened on May 16, 1943, when 19 bomber crews embarked on one of the riskiest missions in WWII."

http://store.aetv.com/html/product/index.jhtml?id=74545

[Keelbuster]

The shape of the shell is not for skipping.

My intuition is that the reason you need a flat stone in order to get a skip is that you are throwing it relatively slow. I imagine that if you fired a round stone fast enough, it would bounce. It would also seem to depend on the angle of impact. But at certain speeds, the water just won't part for an object - like when a person falls out of a plane and hits the water, they bounce:), even though they hit near perpendicular. I figure that with shells travelling so damn fast, and with angles so small, they would often bounce. Some seadog here must have fired a deck gun, and knows the answer....

[Wreford-Brown]

There were many recorded instances in WW2 of damage being caused by ricochets off the water - a number are mentioned in Robert Ballards book on Guadalcanal. Generally a ricochet round had less force than a direct hit and was unlikely to penetrate armoured belts on warships but would play havoc with superstructure and unarmoured areas.

This usually only happened at extreme range when the trajectory of the round was nearly flat (just like skipping stones) and when the water was very calm. The shape of the round is immaterial. The 'bouncing bombs' of Dambuster fame were squat cylinders (like beer barrels) and were made to bounce by creating a rearwards rotation before they were dropped. The rifling on a barrel can cause similar rotation (albeit on a different axis) as does the circular movement put onto a skipping stone as it leaves your hand.

[bigboywooly]

I know the RN of the past used to skip canonballs to increase shot range

@ von stauber

Barnes Wallace was the genius's name

Also designed the 6ton Tallboy and 10ton Grandslam bombs
Fore runner of todays bunker busters

IIRC he also designed the Wellington bomber

[Wreford-Brown]

The Tallboys and Grand Slam were used a great deal against U-boat bunkers in occupied France. The bunkers were too massive to be more than superficially damaged, but a few U-boats were sunk by the giant waves they created washing into the U-boat pens and swamping the deck hatches. After a while, all U-boats were ordered to remain rigged for diving when in the pens with the exception of essential resupply / maintenance and the conning tower hatch.

[Brag]

Interesting comments and info, Guys! :D

[3Jane]

The Italians specialised in using the Ju87 in the 'skip bombing' roll againsed shipping, instead of it's normal use as a dive bomber.

[Keelbuster]

This usually only happened at extreme range when the trajectory of the round was nearly flat (just like skipping stones)

Interesting details - say though, at extreme range, the trajectory should be quite steep, because you have to aim high to lob a shell far - so that gravity can pull it down on your target. Flat trajectories would hold at short range where gravity doesn't have much time to act over the flight path. It seems that you get more skips with a stone when you aim relatively close.

[Wreford-Brown]

@ Keelbuster - you are, of course, right. You get maximum distance from a 45 degree angle, so you're more likely to get skips at close range. Sorry, got my physics messed up.

[Randomizer]

Actually in any long range artillery you get maximum range at quadrant elevations greater than 45 degrees. In 1918 the Paris Gun hit Paris from 110 km using a fixed elevation of 50 degrees. Absolute maximum range was achieved at 55 degress. Another example is the 155mm/45 GC-45, GHN-45 and G-5 family of howitzers that achieve maximum range (40km) at about 860 mils, about 48.4 degrees.

Ricochets are common at low elevations become less likely as elevations increase finally becoming virtually impossible at angles of departure greater than about 24-25 degrees.

On December 8 1914 the old battleship HMS Canopus hit SMS Gneisenau with a 12" practice round that ricochet off the water. Some sources credit HMS Warspite with a first round ricochet hit on the Italian battleship Giulio Cesare at the Battle of Punta Stilo, July 9 1940. The Americans used to skip 500 and 1000 pound bombs off the water when attacking Japanese shipping. The technique proved deadly at during the battle of the Bismarck Sea.

I doubt if SH3 models the effects though.

The potential for ricochets become likely whenever the projectile arrives at a shallow angle of fall.

Good Hunting

[Kpt. Lehmann]

Ricochets are common at low elevations become less likely as elevations increase finally becoming virtually impossible at angles of departure greater than about 24-25 degrees.


Exactly.

I've seen loads of footage of .50 caliber and 20mm tracers ricocheting after being fired at Japanese aircraft attacking U.S. ships in the Pacific. (With a little work... readers should be able to observe this on YouTube.)

Larger projectiles fired at low elevation that fail to detonate on impact with the water exhibit the same behavior. It is just typically less visible since they do not typically emply a tracer element.

[Keelbuster]

Awesome. I don't suppose it's modable in SH3 though...

[Graf Paper]

Wasn't Barnes Wallace also the bright chap who invented the "earthquake" bomb that was used to bring down otherwise bomb-proof structures by creating shockwaves deep in the ground to cause plasticization and thus destabilize a structure to the point that it collapsed under its own weight?

I say! Right jolly, old ruckus that must have been, what! :arrgh!:

Keelbuster, I really have my doubts that bouncing anything could be modeled into SH3.

As often as I've had aircraft I've shot down actually hit my boat, I'm getting suspicious of the devs having programmed in "kamikaze" behavior for aircraft that have been destroyed but the physics of SH3's engine seems to be limited and even some stuff that is implemented is skewed or off-kilter.

[Kpt. Lehmann]

Awesome. I don't suppose it's modable in SH3 though...

Unfortunately it is not.

[marees62]

turns it it is nearly impossible to bomb/damage a dam just by dropping a bomb onto it - so a British enginneer spent his entire war time effort designing a bomb that would be dropped several hundred yards away from the dam, skip on the surface towards the dam, sink when arriving at the dam and then denotate at just the right depth- took years of trial and error to work it all out but he finally got it right and the RAF went wild blowing up germany dams

excerpt from DVD
"In 1943, the war was not going well for the Allies. The Nazis were in firm control of the European coastline and only approachable by air. Engineer Barnes Wallis had a bold (and, many thought, bizarre) idea to turn the war around. His creation--a bouncing bomb--was an innovative blend of simple physics and precision flying with the potential to unleash a torrent of destruction on Nazi industry. MAN, MOMENT, MACHINE details what happened on May 16, 1943, when 19 bomber crews embarked on one of the riskiest missions in WWII."

http://store.aetv.com/html/product/index.jhtml?id=74545


I remember watching a movie a few years ago that was based on that idea. I believe the movie was called "The Dam Busters". Enjoyed it quite a bit. I think they had to modify the bomb bays in order to put a spin on the bombs before they dropped, so that they would "skip" when they hit the water. And the planes had to be going a certain speed and height for this to work properly. And I thing the bombs were round and not the "normal" bomb shape.

[Sailor Steve]

Actually the bombs were the same shape as depth charges, i.e. shaped like a drum.
http://en.wikipedia.org/wiki/Image:Duxford_UK_Feb2005_bouncingbomb.JPG
http://en.wikipedia.org/wiki/Operation_Chastise

Be sure to scoll down the page to the 'Complete List of Aircraft Involved', and see how many of the bombs hit the target with no effect.

[antikristuseke]

Ricochets are common at low elevations become less likely as elevations increase finally becoming virtually impossible at angles of departure greater than about 24-25 degrees.


Exactly.

I've seen loads of footage of .50 caliber and 20mm tracers ricocheting after being fired at Japanese aircraft attacking U.S. ships in the Pacific. (With a little work... readers should be able to observe this on YouTube.)

Larger projectiles fired at low elevation that fail to detonate on impact with the water exhibit the same behavior. It is just typically less visible since they do not typically emply a tracer element.

Usualy when you see tracers ricocheting off water its only the tracer detached from the bullet which bounces off because of the angle at which bullet hits the water.

[Kpt. Lehmann]

Ricochets are common at low elevations become less likely as elevations increase finally becoming virtually impossible at angles of departure greater than about 24-25 degrees.


Exactly.

I've seen loads of footage of .50 caliber and 20mm tracers ricocheting after being fired at Japanese aircraft attacking U.S. ships in the Pacific. (With a little work... readers should be able to observe this on YouTube.)

Larger projectiles fired at low elevation that fail to detonate on impact with the water exhibit the same behavior. It is just typically less visible since they do not typically emply a tracer element.

Usualy when you see tracers ricocheting off water its only the tracer detached from the bullet which bounces off because of the angle at which bullet hits the water.

If you are saying that the bullet itself would not skip or ricochet, you are incorrect sir. What you must realize is that water may as well be concrete when it is struck by an object at high speed... and angle is everything. Projectiles fired from low/flat trajectories, striking a horizontal surface will "skip." Otherwise you could never skip a rock across a pond.

That being said, a projectile striking the face of a wave would penetrate into the water and would likely not ricochet or "skip." (The same would be true of "point-detonation fuses" that strike anything. Instead of skipping, they'd likely just explode on contact with the water.)

If you can "skip" rocks or bombs... you can skip any projectile.;)

[joegrundman]

Solid canonballs fired in the age of sail could skip up to the three times the basic range and proceed to damage other ships.

Source: somewhere in a Patrick O'Brien novel; can't remember which one.

[antikristuseke]

If you are saying that the bullet itself would not skip or ricochet, you are incorrect sir. What you must realize is that water may as well be concrete when it is struck by an object at high speed... and angle is everything. Projectiles fired from low/flat trajectories, striking a horizontal surface will "skip." Otherwise you could never skip a rock across a pond.

That being said, a projectile striking the face of a wave would penetrate into the water and would likely not ricochet or "skip." (The same would be true of "point-detonation fuses" that strike anything. Instead of skipping, they'd likely just explode on contact with the water.)

If you can "skip" rocks or bombs... you can skip any projectile.;)

No, not the usualy at the begining od my post. I said that USUALY its only the tracer that ricochets with the bullet breaking the surface tension of the water and penetratig with the tracer coming off the back of the bullet. At shallow angles bullets can, have and will ricochet. But as i allreayd said most footage of strafing attack by aircraft, on uboats for instance, where you can clearly see tracers ricocheting off water they are no longer attached to the bullet.

[Randomizer]

If you are saying that the bullet itself would not skip or ricochet, you are incorrect sir. What you must realize is that water may as well be concrete when it is struck by an object at high speed... and angle is everything. Projectiles fired from low/flat trajectories, striking a horizontal surface will "skip." Otherwise you could never skip a rock across a pond.

That being said, a projectile striking the face of a wave would penetrate into the water and would likely not ricochet or "skip." (The same would be true of "point-detonation fuses" that strike anything. Instead of skipping, they'd likely just explode on contact with the water.)

If you can "skip" rocks or bombs... you can skip any projectile.;)

No, not the usualy at the begining od my post. I said that USUALY its only the tracer that ricochets with the bullet breaking the surface tension of the water and penetratig with the tracer coming off the back of the bullet. At shallow angles bullets can, have and will ricochet. But as i allreayd said most footage of strafing attack by aircraft, on uboats for instance, where you can clearly see tracers ricocheting off water they are no longer attached to the bullet.

Generally the tracer element is a pyrotechnic compound packed into a hollow in the base of the bullet and covered with shellac to seperate it from the propellent before firing. Sometimes there will be some sort of non-combustable mixture to delay ignition until after the projectile has travelled some distance down range.

Larger projectiles, like an APFSDS penatrator or a direct fire round like HESH tend to have the tracer element (four in the case of 105mm HESH for example), inserted into the base of the projectile in their own little holders. Seperation of the tracer element after impact is unlikely because hitting the ground will cause all components to "set-foward" due to inertia so the tracer elements would tend to stay where they are. That being said, a projectile that ricochets is unstable and may tumble along the long-axis with enough centrifugal force to eject the tracer cups. Cannot recall actually seeing it happen that way but suppose that it is possible.
Good Hunting