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Hydra
01-15-09, 02:13 PM
Does patrolling on the surface with high telescope in SH4 increase your ability to spot ships at a greater distance as it did in RL?

SteamWake
01-15-09, 02:27 PM
Game wise no, in real life not really.

The key thing seems to be to have qualified watch crew on watch. Those guys are good and can spot things over the horizon somehow :hmm:

Hydra
01-15-09, 03:44 PM
I just finished reading Silent Running by James Calvert where he talks about patrolling in the USS Jack in the South China Sea:

By running on the surface and setting a watch on the high periscope, we achieved a significant increase in our coverage. In this condition we had an effective height of eye of fifty feet ... we could see the top of a ship at fifteen miles, her smoke even farther. Thus we were covering an area of more than seven hundred square miles with the high periscope watch, as compared to a maximum of fifty square miles with the submerged periscope watch.

Crew members volunteered for this watch because there was a pool rewarding the first member to spot a target!:yep:

I guess our lookouts are getting some feedback from the volunteers in the conning tower!

aanker
01-15-09, 04:46 PM
I have heard from many RW submariners that the high periscope was used extensively while operating on the surface.

Plug "O'Kane Tang search procedures" into Google and result 1 is an excerpt from "The Bravest Man" - page 196:

"So Tang lay to on the surface, raising her search periscope, which would reach out past the bridge's horizon. Each evening, O'Kane shifted Tang's patrol position about 20 miles" ......

and from an email message on this subject from an old friend:

"This old boat sailor was directed by the Officer of the Deck to man the high periscope a lot while on the surface. When the seas got a bit rough and green water came over the bridge, it was the best way to see a mile or two more. It wasn't easy to stay on the horizon, but we used it."

I wish this high-scope 'extended range' was modeled in SH4.

Happy Hunting!

Art

Rockin Robbins
01-15-09, 08:21 PM
Fluckey also mentions high periscope watch aboard Barb, crediting it for doubling his search radius. If you do the math it isn't quite double, but the area searched is almost quadrupled. Unfortunately the game does not extend the horizon with rising eye height.

tater
01-15-09, 09:39 PM
^^^ sort of amazes me that they'd bother with various useless eye candy, but not get the one of the most important "terrain" features in the game, the whole hull up, hull down paradigm.

Aside from water depth, just about no terrain feature is more important, LOS as a function of height/earth curvature is fundamental.

http://members.spinn.net/~merrick/Stuff/range_table_sm.jpg

Fish40
01-16-09, 05:28 AM
^^^ sort of amazes me that they'd bother with various useless eye candy, but not get the one of the most important "terrain" features in the game, the whole hull up, hull down paradigm.

Aside from water depth, just about no terrain feature is more important, LOS as a function of height/earth curvature is fundamental.

http://members.spinn.net/~merrick/Stuff/range_table_sm.jpg


Very interesting table Tater.:yep: I'm assumeing that the "height of eye" of the observer means the height above the water that a lookout is observing ( ie: out on the conning tower, or up in a crow's nest):hmm:

I'm also wondering how one could accurately measure the distance of where the horizon line cuts the ship's profile?:hmm:

old_tex
01-16-09, 07:06 PM
The formula for Line of Sight is:
distance = Sqrt(2*R*h+(h^2)), where:
R = Radius of the Earth
h = Eye Height

Note: Use the same units for all variables (km, nm, yds, m, etc)

Since the Earth is a Oblate Spheroid (a pear), the diameter and thus the radius varies according to location. The Earth's approximate radius is:
6357 ~ 6378 km
3950 ~ 3963 miles, or 8000067 ~ 8026396 yds (nm = 6076)

Therefore: Using the values in the tables listed in this thread, an Eye Height of 79 ft yields a distance of 20,610 yds.
By the formula, where the Earth's Radius is 8000067 yds and the Eye Height is 26 yds (79/3), the distance to the horizon is 20,527 yds.

That's pretty close! :up: Old_tex

SteamWake
01-16-09, 09:00 PM
we could see the top of a ship at fifteen miles, her smoke even farther. !

That explains those eagle eyes :p

kylesplanet
01-16-09, 09:43 PM
Good table Tater. :up: