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Old 05-28-2001, 12:57 PM
Johnny L.A. Johnny L.A. is online now
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On most large ships and many large boats I've noticed a round transparent disc about a foot across in the front bridge window. I seem to remember seeing a vertical radius in them. What is this? I assume it is some sort of navigation device whereby an object's position can be identified as so-many degrees off of the bow. Is that right? What is it called?
'Never say "no" to adventure. Always say "yes". Otherwise you'll lead a very dull life.' -- Commander Caractacus Pott, R.N. (Retired)

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Old 05-28-2001, 01:11 PM
Rayne Man Rayne Man is offline
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Windscreen Wiper

On some ships that disk is a type of windscreen(shield) wiper. What happens is that the disk spins at high speed and throws all the water off. Thus the crew on the bridge always have an clear area to look through even in very heavy rain or spray
Old 05-28-2001, 01:31 PM
CnoteChris CnoteChris is offline
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Here's a picture of one for those who are curious.
Old 05-28-2001, 01:31 PM
Johnny L.A. Johnny L.A. is online now
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That makes sense. They have the same sort of thing for movie cameras.
Old 05-28-2001, 02:43 PM
ElvisL1ves ElvisL1ves is offline
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The same things are used on the enclosures of some high-speed production milling machines, so the operator can see what's going on through the "rainstorm" of coolant.


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