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Subject: Re: Standard sea level temperature and pressure
From: Gary Harkins (HTYCGARY@XXX.XXX)
Date: Mon Jan 13 2003 - 15:23:40 EST
In a message dated 1/13/2003 2:42:47 PM Eastern Standard Time,
marc.bernstein@XXX.XXX writes:
> For the purposes of correcting sextant altitudes standard sea level
> temperature and pressure (STP) are 10C and 1010mb.
Just a guess, but I would say that it was an arbitrary pick of a
temperature/pressure value that gives the least amount of refraction (as in
zero) and are pretty much central within the temperature and pressure range
that are normally encountered? Your example of 15C and 1013.25mb's would
have worked just as well as it also has zero correction at all values of h
according to table A4.
By the way...any chance that you are related to Norm Bernstein. He owns a
Catalina C400 and is a member of that email list.
Gary Harkins C400 #140 "Cygnus"
Website http://www.hometown.aol.com/htycgary/myhomepage/index.html
Harbour Towne Marina, Muskegon, Michigan Slip C-28
Harbour Towne Yacht Club, Life Member
C400 National Association
United States Power Squadrons-JN
NRA Life Member
MCRGO (Michigan Coalition for Responsible Gun Owners)
JPFO (Jews for the Preservation of Firearms Ownership)
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