Ever pulled a Capt. Dodge?

[desirableroasted]

The link I uploaded indicated that 20-30 meters of underwater visibility is pretty fantastic. But let's assume it's average.

Even then, since a VIIC is 67 meters long, you'd still be extraordinarily lucky to see your own bow. And at 6 knots, which is about the speed you'd have to have under a merchant, (and you have to assume he is not zigging), you are eating up 3 meters a second. You'd never avoid anything in front of you... the math doesn't allow it.

So I suspect the reason there is no documentation from wartime is that U-boat captains -- who, as a rule, probably forgot more physics and mathematics than most of us will ever learn -- never even considered it.

[Puster Bill]

Originally Posted by desirableroasted

The link I uploaded indicated that 20-30 meters of underwater visibility is pretty fantastic. But let's assume it's average.

Even then, since a VIIC is 67 meters long, you'd still be extraordinarily lucky to see your own bow. And at 6 knots, which is about the speed you'd have to have under a merchant, (and you have to assume he is not zigging), you are eating up 3 meters a second. You'd never avoid anything in front of you... the math doesn't allow it.

So I suspect the reason there is no documentation from wartime is that U-boat captains -- who, as a rule, probably forgot more physics and mathematics than most of us will ever learn -- never even considered it.

I've been at least 25 meters deep in the ocean, and it seems to me that during daylight hours you could look straight up and be able to see if there was a ship above you under almost all but the very poorest visibility. When there is a large contrast (light surface, dark ship) like that, you don't have to be able to see details in order to perceive that something is above you.

Provided the periscope could handle being unhoused at 25 meters, of course. Anyone remember how deep U-977 was when her observation scope was busted due to being left up during a dive?

He has a point, try it out in GWX go down to a depth where your sub dissapears in free cam, then twist the cam so youre looking up at the surface, ive done this and the sub became immediately visible in close to 70m of water (not for sure on the depth just using a number) now at night, its darn near impossible even at P depth.

Originally Posted by Puster Bill

I've been at least 25 meters deep in the ocean, and it seems to me that during daylight hours you could look straight up and be able to see if there was a ship above you under almost all but the very poorest visibility. When there is a large contrast (light surface, dark ship) like that, you don't have to be able to see details in order to perceive that something is above you.

Provided the periscope could handle being unhoused at 25 meters, of course. Anyone remember how deep U-977 was when her observation scope was busted due to being left up during a dive?

[desirableroasted]

Originally Posted by USNSRCaseySmith

He has a point, try it out in GWX go down to a depth where your sub dissapears in free cam, then twist the cam so youre looking up at the surface, ive done this and the sub became immediately visible in close to 70m of water (not for sure on the depth just using a number) now at night, its darn near impossible even at P depth.

Yeah, in the game it is possible. I think we are trying to figure out if it was possible in real life and, if not, making a note to not exploit the game in the future.

To take another example, clicking the "lock" function in the periscope or UZO lets you "see" ships 6 or 7 nm away, even in dense fog... not possible in real life, so it's up to the player to decide whether to exploit that or not

[desirableroasted]

Originally Posted by Puster Bill

I've been at least 25 meters deep in the ocean, and it seems to me that during daylight hours you could look straight up and be able to see if there was a ship above you under almost all but the very poorest visibility. When there is a large contrast (light surface, dark ship) like that, you don't have to be able to see details in order to perceive that something is above you.

Provided the periscope could handle being unhoused at 25 meters, of course. Anyone remember how deep U-977 was when her observation scope was busted due to being left up during a dive?

I am not a diver, but diving friends tell me the difference between a sunny, clear day and a cloudy one is enormous even at fairly shallow depths (and not being a diver, I don't know how deep that is, but certainly not more than we are talking about).

It certainly seems plausible that you could look up with the scope at a fairly shallow depth and see the shadow of a ship, if the sun was right. Makes sense. But keeping it in sight while you align your boat and match its speed (especially if it is weaving) seems a whole 'nother problem.

[JokerOfFate]

I agree with Roasty here on a lot of stuff but heres my case,

"So I suspect the reason there is no documentation from wartime is that U-boat captains never even considered it."

I agree with most of that but not many people came back, so the likelihood of their being any documentation is small.

"clicking the "lock" function in the periscope or UZO lets you "see" ships 6 or 7 nm away, even in dense fog... not possible in real life, so it's up to the player to decide whether to exploit that or not"
Not true, the smoke from some ships can be seen from miles away, making it possible.

"And at 6 knots, which is about the speed you'd have to have under a merchant, (and you have to assume he is not zigging), you are eating up 3 meters a second. You'd never avoid anything in front of you... the math doesn't allow it."

What about the variables there, was the merchant hit, sabotage or a malfunction.

Now, I know for a fact that if things are not going your way on a battlefield then you'll use every trick and break every rule/restriction to get your boys out alive, so maybe it did happen, heck maybe it worked but they just didn't make it back to spread the news

[JokerOfFate]

So as far as I see it, there's no way to prove whether or not they did do it.

So I think we should just call it a matter of debate and do what you see fit because no matter what its a 50-50 of being real or fake.

[desirableroasted]

Originally Posted by JokerOfFate

"clicking the "lock" function in the periscope or UZO lets you "see" ships 6 or 7 nm away, even in dense fog... not possible in real life, so it's up to the player to decide whether to exploit that or not"
Not true, the smoke from some ships can be seen from miles away, making it possible.

Obviously, I wasn't clear enough.

Even in dense fog, when using the UZO or periscope, and clicking "lock" as you look around, you can detect ships out to the horizon (actually, far over the horizon). This is clearly impossible, and using it is a "game exploit."

You simply cannot see that far unless the conditions are perfect.

I live on a cliff overlooking the ocean. On a clear day, with excellent conditions, I can spot ships 9-10 nm out. I can promise you that the least bit of haze reduces that by half, and fog brings it down to 100 m.

[Draka]

One of the very first things any sailor learns is that height above water equals sighting distance to the horizon - the view from the deck of nearly any ship is far better than from the conning tower of a Uboote, much less from the periscope only barely above water. I lived on a sailboat in the Bay Area (San Francisco, CA) for seven years - and the fog there is infamous. Trust me, there were many days I couldn't see the bow from the helm position - a matter of 20 feet! Haze/fog is a killer for any Mark I eyeball visuals ....

[timmy41]

Originally Posted by JokerOfFate

"clicking the "lock" function in the periscope or UZO lets you "see" ships 6 or 7 nm away, even in dense fog... not possible in real life, so it's up to the player to decide whether to exploit that or not"
Not true, the smoke from some ships can be seen from miles away, making it possible.

you can see a ships smoke 6-7 km away in thick fog?

[JokerOfFate]

Originally Posted by timmy41

you can see a ships smoke 6-7 km away in thick fog?

I was referring to normal conditions and some weathers But not in thick fog.

Please use common sense its a wonderful gift

[timmy41]

Originally Posted by JokerOfFate

I was referring to normal conditions and some weathers But not in thick fog.

Please use common sense its a wonderful gift

The situation being discussed was thick fog.

Please learn comprehension of semantics, its a wonderful gift.

[Puster Bill]

Originally Posted by desirableroasted

I am not a diver, but diving friends tell me the difference between a sunny, clear day and a cloudy one is enormous even at fairly shallow depths (and not being a diver, I don't know how deep that is, but certainly not more than we are talking about).

It certainly seems plausible that you could look up with the scope at a fairly shallow depth and see the shadow of a ship, if the sun was right. Makes sense. But keeping it in sight while you align your boat and match its speed (especially if it is weaving) seems a whole 'nother problem.

Well, for the purposes of a reload, you don't have to be under there for very long, and you don't have to be *RIGHT* underneath a ship, just close enough that the escorts can't effectively get to you.

If you had done your work correctly, you know the course and speed of the convoy, and unless they zig or the convoy breaks up, you know direction and speed of any individual ship within the convoy.

On considering this, though, I won't attempt it using the obs scope anymore (not that I commonly did it anyway), when I do it I'll do it by sound only. You should be able to tell when you are close enough by a rapid bearing change on the hydrophones, and you should be able to get close enough to avoid a destroyer attack by sound alone.