|

Distance between range lights

Trivia! Trivia! Trivia! All lighthouse and life saving station trivia, as well as any contests or contest links!

Postby island » Wed Apr 06, 2005 5:24 am


There is a pair of range lights in the US where the rear range light is located almost 4 miles inland from the front range light. The focal plane of the rear light is 75 feet* above that of the front light. What range is this?

*Correction: 131 feet, not 75 feet.
Last edited by island on Wed Apr 06, 2005 1:26 pm, edited 1 time in total.
island
Lt. Commissioner
 
Posts: 2035
Joined: Fri Dec 13, 2002 1:00 am

Postby Hersh » Wed Apr 06, 2005 9:35 am


Wow, that's a good one....
Mike Hershberger
Quidquid latine dictum sit, altum viditur

Image
http://www.harbor-of-refuge.com
User avatar
Hersh
Lighthouse Master
 
Posts: 3970
Joined: Sat Jun 28, 2003 12:00 am
Location: Goshen, IN

Postby Pharoslvr » Wed Apr 06, 2005 10:04 am


The range of the rear light is 14.27 nautical miles

Brent
Pharoslvr
"A smooth sea never made a skilled mariner" British Proverb

<img src="images/SmallOBLHSlogo.jpg">

1995 Charter Member
User avatar
Pharoslvr
Lighthouse God
 
Posts: 5234
Joined: Thu Oct 31, 2002 1:00 am
Location: Southern Virginia

Postby island » Wed Apr 06, 2005 1:24 pm


Error in the description above. :?

The height difference between front and rear is 131 feet as determined from the CG 2005 Light List, not 75 feet as I had stated incorrectly.
island
Lt. Commissioner
 
Posts: 2035
Joined: Fri Dec 13, 2002 1:00 am

Postby ron » Wed Apr 06, 2005 7:30 pm


well now you tell me after spending the looking for 75 feet separation
User avatar
ron
Head Keeper
 
Posts: 320
Joined: Tue Apr 08, 2003 12:00 am

Postby island » Wed Apr 06, 2005 8:01 pm


Sorry about that. Did you lean something new in your search?

Frankly I goofed when I used range light tower height instead of focal plane height when I posted the wrong difference in height. It did not look right so I went to the Light List and discovered my error.
island
Lt. Commissioner
 
Posts: 2035
Joined: Fri Dec 13, 2002 1:00 am

Postby bert911 » Thu Apr 07, 2005 8:26 am


Liston Range Lights, Fort Penn, DE?

http://www.beaconsofhope.com/liston.htm
User avatar
bert911
Assistant Inspector
 
Posts: 891
Joined: Tue Aug 19, 2003 12:00 am
Location: Winterville North Carolina

Postby island » Thu Apr 07, 2005 10:40 am


You got it, Bert.

The distance between Liston Range front and rear lights is unusually long, 6760 yards (3.8 statute miles). The rear fixed white light has a 2nd order lens and with a geographic range of 19+ miles but can be seen much further from the bridge elevation of the large ships transiting the very long Liston Range, said to be the longest in the U.S.. The southerly entrance to this range is about 24 NM from the rear light. The long distance to the entrance to the range is the reason for the long distance between range lights. If the range lights were too close together it would be difficult to use them for proper alignment when entering the range. The front range light has a focal plane of 46 feet and the light characteristic is Iso 6 seconds.

Brent.
What range lights did you find initially using the wrong height difference I posted at first?
island
Lt. Commissioner
 
Posts: 2035
Joined: Fri Dec 13, 2002 1:00 am


Return to Lighthouse Trivia & Contests

Who is online

Users browsing this forum: No registered users and 1 guest

cron