What happens when...

[Foghladh_mhara]

Lightning strikes a U-Boat?

Reading a book by Edward Young who was the first RNVR Officer to join the RN Submarine branch. In it he describes a passage across the Med as the watch officer. All of a sudden an electrical storm started and a fork of lightning hit the sea a bit too close for comfort. He made the decision to dive because he didn't know what the result of a lightning strike on 700 tons of steel surrounded by water would be.

Any ideas?

[BelegDraug]

Mmmhhh... interesting topic.- Maybe it could just happen like in a car, a Faraday effect where the electrons go around all the trip on the metal not damaging the people inside it... but, I don't know the "neutral" parts of a sub's interior and how could it be isolated from the current... (in a car, for example, we have plastic pieces and a metal chassis)

[Stealth Hunter]

We must remember, children, a U-boat carries EXPLOSIVES on board. You might find that the entire thing would blow up.

[BelegDraug]

Well, maybe you are right my little boy... but not all the explosives would explode when they are hit by a current... even the WWII explosives... I don't know the exact composition of a T2 explosive head, but maybe the Faraday effect would protect them from an explosion, just by discharging the current away.-

[Stealth Hunter]

Perhaps...:hmm:

And I'm 47, not a child.

[Foghladh_mhara]

Perhaps...:hmm:

And I'm 47, not a child.

So why are you playing at being a u-boat commander? At least I have an excuse...I'm only 33 :)

[BelegDraug]

Je, je... I'm 27 here... And perhaps, maybe you just get lucky and it doesn't explote... Sincerely, I don't know if the T2 would explode or not with the current from a lightning. Maybe some research would help... but I think it's a good question... Ahoy, Kaleun!!!

[KeybdFlyer]

Apologies for jumping in with an unrelated topic. Stealth_Hunter? Could you confirm you got my PM ref. the sig image? Got to drop offline shortly. Thx.

[Puster Bill]

Well, maybe you are right my little boy... but not all the explosives would explode when they are hit by a current... even the WWII explosives... I don't know the exact composition of a T2 explosive head, but maybe the Faraday effect would protect them from an explosion, just by discharging the current away.-
Don't forget, it isn't just the explosives themselves, but the pistols (ie., fuzes). They tend to use much more sensitive explosives to set off the less sensitive (but more powerful) main charge.

You've also got AA and deck gun ammunition to worry about, especially those in 'ready' containers outside the hull.

Then too, you have things that don't react well to overcurrents and overvoltages, like batteries, motors, and various electrical circuits.

[Brag]

Well, maybe you are right my little boy... but not all the explosives would explode when they are hit by a current... even the WWII explosives... I don't know the exact composition of a T2 explosive head, but maybe the Faraday effect would protect them from an explosion, just by discharging the current away.-
Don't forget, it isn't just the explosives themselves, but the pistols (ie., fuzes). They tend to use much more sensitive explosives to set off the less sensitive (but more powerful) main charge.

You've also got AA and deck gun ammunition to worry about, especially those in 'ready' containers outside the hull.

Then too, you have things that don't react well to overcurrents and overvoltages, like batteries, motors, and various electrical circuits.

All these scary things on board? Maybe I ought to request a transfer to the Red Cross.:o

[bigboywooly]

All these scary things on board? Maybe I ought to request a transfer to the Red Cross.:o

Doubt they would have you
You have provided quite a few of their " customers "
:rotfl:

[Stealth Hunter]

Perhaps...:hmm:

And I'm 47, not a child.

So why are you playing at being a u-boat commander? At least I have an excuse...I'm only 33 :)

You have no excuse, you damn Irishman.:rotfl:

Anyway, it never hurts to use a little bit of imagination for some immersion... just as long as you don't go too far, or you risk going Gothic.

[Hadrys]

Ekhem wouldn't it be the same case with everything that floats and is made from steel? ;)

Once we were diving in a small flooded excavation. But with heavy overcast from all the sudden and lightnings we felt we should get the ... out of there ASAP ;) But still I don't know how it would effect us and probably don't want to try this on my skin ;)

[Foghladh_mhara]

Well my grasp of physics is on a par with my grasp of computers, I know the stuff works but I'm buggered if I know how.

In cars its the tyres that prevent the charge earthing isn't it?

But what happens the unlucky kaleun who sticks up his scope, grips the handles and gets a lightning strike? Whilst standing in his steel tube surrounded by extremely conductive salt water!!

I assume the GWX team haven't factored this scenario in :p

[Paajtor]

I am not sure, whether the Faraday-effect would protect crew & boat entirely.
Maybe the ocean-water conducts lightning better than a metal Uboat? If so, then lightning would find an easier channel straight towards the ocean-surface, then to a Uboat.

But I do know, that lightning is a pretty rare event out on the open oceans.
Check this map (http://science.nasa.gov/headlines/images/lightning2/lightningmap_large.gif)....taken from this article (http://science.nasa.gov/headlines/y2001/ast05dec_1.htm?list69136).

Lightning. It avoids the ocean, but likes Florida. It's attracted to the Himalayas and even more so to central Africa. And lightning almost never strikes the north or south poles. These are just a few of the things NASA scientists have learned using satellites to monitor worldwide lightning.

[Tom]

I am not sure, whether the Faraday-effect would protect crew & boat entirely.

It should. All the electricity should stay on the outer surface of the boat. However, if the boat was on the surface when the lightning struck, there would probably be lookouts on the bridge. And since the bridge was the highest part of the boat... well, I wouldn't want to be one of the lookouts. Even if the lightning struck some other part than the bridge, the potential differences caused by the current of the lightning would likely cause a nasty (if not lethal) shock.

You've also got AA and deck gun ammunition to worry about, especially those in 'ready' containers outside the hull.

If the containers were metal, the faraday-effect should keep the electricity outside. And if they weren't metal, they most likely weren't conductive enough for much electricity to pass inside.

[KeybdFlyer]

Decided to test Faraday Cage effect during last night's thunderstorm. Sat in a tin bath of water on front lawn. Am now devoid of all body-hair and have difficulty hearing approaching DDs. Please advise.

[IrischKapitan]

I am not sure, whether the Faraday-effect would protect crew & boat entirely.
Maybe the ocean-water conducts lightning better than a metal Uboat? If so, then lightning would find an easier channel straight towards the ocean-surface, then to a Uboat.

But I do know, that lightning is a pretty rare event out on the open oceans.
Check this map (http://science.nasa.gov/headlines/images/lightning2/lightningmap_large.gif)....taken from this article (http://science.nasa.gov/headlines/y2001/ast05dec_1.htm?list69136).

Lightning. It avoids the ocean, but likes Florida. It's attracted to the Himalayas and even more so to central Africa. And lightning almost never strikes the north or south poles. These are just a few of the things NASA scientists have learned using satellites to monitor worldwide lightning.



Water naturally isnt a very good conducter, but of course it will conduct but not to the same degree as lets say, copper. To increase the conductivity of water, some sort of acid would have to be added to it (any physics student should know this). Also lighting srickes the highest thing from ground leval no matter if its wood or lets say, a U-Boat.

The farady effect would not occour (someone will probably tell me I'm wrong) because the U-boat is earthed all the time from the water and thus sending the charge down to the bottom....

What would happen to the men inside ? I dont really know, and I sure as hell dont want to be the one who finds out!

[Foghladh_mhara]

Decided to test Faraday Cage effect during last night's thunderstorm. Sat in a tin bath of water on front lawn. Am now devoid of all body-hair and have difficulty hearing approaching DDs. Please advise.

Repeat experiment whilst holding a long metal object to simulate the periscope. Your doing good work there and we all appreciate it. If you dont report back within 12 hours we'll have the answer to the question one way or another :up:

[Growler]

Hmmm...

Interesting topic. Something to consider, in all our deliberations on this one.

I can't speak for the Kreigsmarine, but I know that on many steel-hulled US vessels, a sacrifical anode is suspended from the ship's hull (underwater). Here's a good description from Wiki:
In cathodic protection, a metal anode that is more reactive to the corrosive environment of the system to be protected is electrically linked to the protected system, and partially corrodesironsteel ship's hull may be protected by a zinc sacrificial anode, which will dissolve into the seawater and prevent the hull from being corroded. Sacrificial anodes are particularly needed for systems where a static charge is generated by the action of flowing liquids, such as pipelines and watercraft. or dissolves, which protects the metal of the system it is connected to. As an example,iron or steel ship's hull may be protected by a zinc sacrificial anode, which will dissolve into the seawater and prevent the hull from being corroded. Sacrificial anodes are particularly needed for systems where a static charge is generated by the action of flowing liquids, such as pipelines and watercraft.
At least one anode is found in tank-type hot water heaters. The anode should be removed and checked yearly, and replaced if 6 inches (15 cm) or more of bare wire is showing. This will greatly extend the life of the tank.

Note the last part about a hot water tank; a good wrench, and you can see what that anode looks like for yourself.

I would surmise that such a sacrificial anode would serve a dual purpose of "grounding" any current from a lightning strike to the water around the exterior hull, in addition to protecting the hull from corrosion, but I'm only guessing.

I know that the Taney, in Baltimore, also has a steel grounding cable from her hull to a pierside cleat, to dissipate any lightning that may hit that ship. Whether or not this serves to alleviate the hit her anodes would take, I don't know.

Anyway, just something to think about.