Ships Antennas

In the early days of wireless communications ships were festooned with antenna cables from bow to stern. In this time and day why are there
still remnants of these (antenna) cables? Civilian ships (VLCC tankers, container-ships, Cruise liners) don't have them. So what kind of function do they serve on warships other than for flying pennants?
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PaPa Peng wrote:

...are you sure they're actually antennas?
--
- Rufus

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The Navies don't always trust modern technology - and they do communicate quite a bit more than most civilian ships. A modern naval vessel typically have both HF (Wire like antennas), VHF (Staf like antennas) and UHF (Very small staf like antennas) as well as several satcom antennas - They also carry several raders for different purposes, whereas most civilian cary one or two.
Claus Gustafsen, MCPO RDN
"PaPa Peng" skrev i meddelelsen
In the early days of wireless communications ships were festooned with antenna cables from bow to stern. In this time and day why are there still remnants of these (antenna) cables? Civilian ships (VLCC tankers, container-ships, Cruise liners) don't have them. So what kind of function do they serve on warships other than for flying pennants?
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Don't forget that HF can also use whip antennas. An example in Australia use was the AN/URT-23V used on Fremantle-class patrol boats.
On 7/01/2012 00:53, Claus Gustafsen wrote:

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snipped-for-privacy@gmail.com says...

Somehow the internet ate my reply, so I'll try again. Most warships no longer use cable antennae for HF (unless it's a jury rig to replace a damaged whip). Those large whip antennae (10m or more tall) are the HF antennae installations on modern warships. Very often you'll see them on top corners of the bridge superstructure. They make a handy reference point for stationkeeping (Keep them in a row and you know you're exactly abeam the other ship).
The cables you see are most often temporary strongbacks which the Deck Dapartment rigs as necessary (usually as you note to carry the pennants when the ship is dressed overall). Modern masts don't need any standing rigging which used to be used, so it's all temporary now.
J <3
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Thanks everyone. My interest came from watching a fascinating PBS broadcast on Mandelbroot fractals. The particular application that caught my attention was the invention of the fractal antenna that was not only small in size but could also receive signals over a broader range of frequencies. [http://www.google.ca/search ? q=fractalantennas&hl=en&client=firefox-a&hs=OZu&rls=org.mozilla:en- US:official&prmd=imvns&tbm=isch&tbo=u&source=univ&sa=X&ei=YUcNT- n2H6iniALpvrH0Aw&ved IQBELAE&biw80&bih`5] That's the reason why the latest cell phones no longer have those stubby antennae and can pack their electronics into the ultra thin handsets we now have.
Now I am sure fractal antennae can also be used on ships - versatile, small, compact, low profile and sturdy, can operate in an enclosed weatherproof shell.This opens up many ship architecture possibilities. The design feature I am interested in is a streamlined weatherproof outer shell over the superstructure that also presents a minimal radar and thermal signature. For quick action just blow off (explosive bolts) the disposable outer shell and fire whatever missiles and guns that can be brought to bear on the enemy. In modern warfare between peers the first one that fires and gets a hit wins. There are no second chances or comebacks.
Any flaws in the argument?
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snipped-for-privacy@gmail.com says...

The reason Stealth surface ships don't work. You *can* make a low-observable ship which is effectively invisible to radar, but the enemy's lookouts can still see it, and there's this inconvenient little thing called 'sea clutter'; radar returns from the water's surface. A Stealth ship shows up as a 'hole' in the sea clutter, making it just as visible to a properly tuned radar as if it were not Stealthy.
Besides which, those covers would be expensive, and what do you do once you've blown them off? Can you also guarantee that the covers would actually blow off once they've been overpainted a couple hundred times by the crew doing routine maintenance? (Remember, ships and weapons need to be sailor-proof)
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<Jessie_C> wrote in says...

From what I've seen/read, then idea isn't to hide the ships so much as to produce a false signature that makes them look smaller.
--
Words of wisdom

What does not kill you... probably didn't cause enough tissue damage.
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No_email_for snipped-for-privacy@wahoo.com says...

That's been the way things have been heading these past 20-odd years. Reducing radar cross-section is a Good Thing : ) There's no sense making the Bad Guys' job any easier...
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<Jessie_C> on Wed, 11 Jan 2012 08:03:47 -0800 typed in rec.models.scale the following:

    The trick to Stealth, like all camouflage efforts, is not so much to "make invisible" as to "In the time they have to 'look', they 'see' what you want them to see." I.e., "not a target".     I came a cross a photograph of a B52 which had made a fly by of a US Aircraft Carrier. According to the story, the BUFF had the carrier in sight before the carrier had located it. It might have had some thing to do with the fact that the BUFF was cruising along at about flight deck height - and the Air Force paint job makes airplanes blend into the "sea haze".
    In other words, I don't have to be invisible all the way, just until I get you into range.

    Far better, IMHO, would be to make the "covers" actually part of the ship, and have ports for the missile launchers. Guns will be a different problem, but not insurmountable.
--
pyotr filipivich
"History rarely repeats herself" is the cliche. In reality she just
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