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- - Am I the only one who... (https://www.subsim.com/radioroom/showthread.php?t=168682)

Am I the only one who...

...uses his periscope underwater? :D Once followed a merchant vessel down to 60 meters with my observation scope. It's also neat watching those depth charges come down...:-?

in real life one could not up the scope beyond 20 meters deep due to the pressure of the water, and the fact that if one was somehow strong enough to, it would break the seal and allow water to pour in. Also, water in real life is often murkier than it is in game.
but none of those limitations are modeled.

just an FYI hahaha.

often i simply dont raise it when under attack due to fear of damaging it.

I used to do that with stock SH3, but GWX bumps the visbility way down, so it's like looking through frosted glass.

I remember raising my periscope at lower than periscope depth in 688(I), resulting in a flooded periscope. This was back when I was a dumb kid, so I'm a bit smarter now (I'll still forget to lower the periscopes in GWX and TMO on common occasion!). :dead:

I doubt they'd be able to see much beyond the subs bow in those RL murky Atlantic waters.

I doubt you would be able to raise it to begin with due to water pressure. If you did manage you would end up flooding your control room. They were not meant to be used beyond a certain depth.

I always figured those scopes were hydraulically actuated with the way they sound when going up.

also they were not meant to be used while moving fast, anything over 2 knots would damage/shear it off

Hard to believe it was quite that fragile, sir. Anything over two knots would certainly feather the surface and give you up, though.

Well it wouldn't break that fast, but the vibration would get worse as the speed increased, which would lead to damage. Same deal with the snorkel.

You wouldn't have to push it up to full extension if you were mucking about submerged, though.

They were very susceptible to speed. They would start vibrating above 3-4 kts and above 5-6 they would bend backwards or break off due to the water pressure.

Think about it for a sec we are talking about extending a hollow metal tube 2" diameter 14-16 meters up while moving at over 10km an hour. A basketball hoop is 3 meters off the ground. We are talking about a distance FIVE times that.

Nuff said.

6 Knots max with periscope raised:

Quote:

Periscopes suffered from two main problems, the most important was vibration. When fully extended, the long unsupported tube created turbulence on a moving U-boat. At 6 knots, it caused excessive vibration which rendered it almost impossible to use. This was dampened by using an extension bracket to reduce the unsupported length and the pointed end was redesigned to minimize the forward hydrodynamic resistance. Nevertheless, vibrations still occurred, but to a much lesser degree. The other problem was fogging of the lenses. Since the damp atmosphere of the U-boat caused fogging, it was especially important that the tube was not only watertight, but was airtight as well. Any fracture on the airtight casing caused by a depth charge attack would result in fogging of the tubes.

http://www.uboataces.com/periscopes.shtml

The same restriction was encountered with the snorkrl:

Quote:

Another problem with running the diesels submerged was in the engine noise. As diesel engines were much noisier than their electrical counterpart, this meant that the U-boat’s hydrophones could not be used. The U-boat still had to rely on the limited view provided by the periscope, but to add to the problem, the periscope could not be used at speeds of over six knots.

http://www.uboataces.com/snorkel.shtml

Some more info but without any reference to speeds:

http://www.uboatarchive.net/BDUOrder2.htm