Distance to Horizon

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rclark
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Distance to Horizon

Post by rclark »

I know this seems like a stupid question. With the Bismarck sitting in an open body of water (or any ship) how far off is the horizon? With the biggest guns the Bismark had, could she fight a battle with the othe ship out of sight or over the horizon. As a crewmember on an allied ship that would be very scary not know when something was coming.
Bgile
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Post by Bgile »

Visual range depends on weather and on the curvature of the earth’s surface. I believe you can see the surface of the water from a large ship out to about 20 to 25 kyds, depending on the weather and the hight of your ship's lookout position.

You can fire further than that. In perfect weather, firing range depends on the highest point of observation on the firing ship and on the highest visible point on the target, assuming your guns can shoot that far.

If you can see the target, it can probably also see you.

The furthest known hits in WWII were achieved at about 27,000 yds. In 1944 radar assisted fire was attempted at very long range at a Japanese destroyer, but given up when the range had opened to about 38,000 yds. No hits were achieved, although the target was straddled.

IMO it would be terrifying to be under battleship fire no matter what you were on.
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Gary
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Post by Gary »

Hi Rev Clark

Scharnhorst hit Glorious at 26,465 yards and Warspite hit Gulio Cesare at about the same range.
Both Scharnhorst and Warspite are recognised as sharing the record for the longest hit on a moving target.

After Modernistaion Warspite could shoot to about 32,000 yards whilst the un-modernised British ships ("R" class, Barham, Malaya and Repulse) were limited to 23,500 yards.

Scharnhorst could, in theory, shoot to over 40,000 yards away but the chances of her obtaining a hit at that extreme range were virtually nil.
I believe only Yamato could shoot further than Scharnhorst.

Both Bismarck and Prince of Wales could shoot to about 38,000 yards.

Image

The above photograph was taken at Jutland - note the colossal fountains of water from the shell splashes :cool:
God created the world in 6 days.........and on the 7th day he built the Scharnhorst
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Re: Distance to Horizon

Post by Tiornu »

Firing over the horizon via optical control is possible, but not likely to produce many hits. The USN felt that gunnery by top spot was limited to about 20,000 yards even for battleships. This is admittedly a conservative figure, but plans for gunnery at long range usually included spotting by aircraft or other ships. The advantages of radar are obvious. It removes a lot of the guesswork of range-finding and spotting, but few WWII radars were capable of providing useful information on target bearing--it's great to know how far to shoot, but even better if you know the proper direction! Consequently, gunnery officers were happiest when they could use their eyes and their radars.
So was it prodigal to build a gun mount giving a range of 38,000 yards? Even before radar, guns usually had more range than optical fire control could manage simply because a damaged ship might be listing to one side and thus not able to raise its guns to the maximum elevation. So Bismarck, listing 10deg, might have its gun range cut to 30,000 yards or so.
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Re: Distance to Horizon

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Ulrich Rudofsky
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Post by Ulrich Rudofsky »

With the Bismarck sitting in an open body of water (or any ship) how far off is the horizon?
Most people greatly overestimate how far they can see at sea.

Take X as the eye level of the observer in a line to the center of the earth. This triangle has a length of b = 6371 km plus the eye level height H. For example, this would be about 1.70 m for an adult. According to Pythagoras this equals: ‘a’ squared + X squared = ‘b’ squared, i.e., X squared = (a+H) squared – ‘a’ squared. Now you can calculate the distance of X to the horizon. In the end you derive a formula were X = 3.75 times the root of H, where X is in km, if you enter H in meters. So let us enter the height of the eye at H = 1.70 m, then the distance to the horizon equals about 4.7 km. A child would instead see the distance, at an eye height of 1 meter, as about 3.6 km. Accordingly, in a ship’s crows nest of 30 m height a lookout would have a visibility of about 20 km; however, a 30 meter high ship would be recognized by the lookout at a distance of about 40 km.

http://www.deutschekriegsmarine.de/Will ... ssung.html
Ulrich
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