NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: ball drop sextant report, 1949
From: Robert Eno
Date: 2006 Sep 20, 21:18 -0500
I have a ball drop sextant in my collection, along with the operation
manual. It includes the principle of operation. I can scan it in for anyone
who wants to have a look.
It is a cumbersome piece of gear and I honestly cannot figure out why or how
the designers believed that this would be a workable instrument.
Robert
----- Original Message -----
From: "Paul Hirose" <cfuhb-acdgw@earthlink.net>
To: "Google nav list" <NavList@fer3.com>
Sent: Wednesday, September 20, 2006 12:45 AM
Subject: [NavList 1304] ball drop sextant report, 1949
>
> In the U.S. Dept. of Transportation archives I found a 1949 Civil
> Aeronautics Administration report on a new aircraft sextant of the "ball
> drop" type, developed by the U.S. Naval Observatory. The CAA tested it
> against a conventional Pioneer bubble sextant, best known by its
> military designation AN5851-1 or A-14.
>
> The ball drop sextant performed poorly. "The only possible conclusion to
> be reached from the flight tests is that the ball drop sextant fails by
> a great deal of attaining the accuracy necessary for celestial
> navigation in the air."
>
> Unfortunately, the report does not go into its principle of operation
> much beyond "the ball drop sextant uses the line of fall of a small
> steel ball to establish a vertical line".
>
> You will have to navigate to the page. My attempts to create a clickable
> link have failed, probably due to the way Javascript is used at the
> site. Also, if you have Internet Explorer's security settings turned up,
> it will be necessary to add the site IE's list of trusted sites.
>
> http://dotlibrary.specialcollection.net/
>
> Click "FAA and CAA Research Reports"
> Click "CAA TECHNICAL DEVELOPMENT REPORTS"
> Then look for the ball drop sextant report (the browser Search function
> will find it if you enter "sextant").
> The page has an small portion of the report, and a link to download a
> PDF scan of the whole thing, which is about 1.2 MB.
>
> --
> I block messages that contain attachments or HTML.
>
>
>
>
>
> >
--~--~---------~--~----~------------~-------~--~----~
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To , send email to NavList-@fer3.com
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From: Robert Eno
Date: 2006 Sep 20, 21:18 -0500
I have a ball drop sextant in my collection, along with the operation
manual. It includes the principle of operation. I can scan it in for anyone
who wants to have a look.
It is a cumbersome piece of gear and I honestly cannot figure out why or how
the designers believed that this would be a workable instrument.
Robert
----- Original Message -----
From: "Paul Hirose" <cfuhb-acdgw@earthlink.net>
To: "Google nav list" <NavList@fer3.com>
Sent: Wednesday, September 20, 2006 12:45 AM
Subject: [NavList 1304] ball drop sextant report, 1949
>
> In the U.S. Dept. of Transportation archives I found a 1949 Civil
> Aeronautics Administration report on a new aircraft sextant of the "ball
> drop" type, developed by the U.S. Naval Observatory. The CAA tested it
> against a conventional Pioneer bubble sextant, best known by its
> military designation AN5851-1 or A-14.
>
> The ball drop sextant performed poorly. "The only possible conclusion to
> be reached from the flight tests is that the ball drop sextant fails by
> a great deal of attaining the accuracy necessary for celestial
> navigation in the air."
>
> Unfortunately, the report does not go into its principle of operation
> much beyond "the ball drop sextant uses the line of fall of a small
> steel ball to establish a vertical line".
>
> You will have to navigate to the page. My attempts to create a clickable
> link have failed, probably due to the way Javascript is used at the
> site. Also, if you have Internet Explorer's security settings turned up,
> it will be necessary to add the site IE's list of trusted sites.
>
> http://dotlibrary.specialcollection.net/
>
> Click "FAA and CAA Research Reports"
> Click "CAA TECHNICAL DEVELOPMENT REPORTS"
> Then look for the ball drop sextant report (the browser Search function
> will find it if you enter "sextant").
> The page has an small portion of the report, and a link to download a
> PDF scan of the whole thing, which is about 1.2 MB.
>
> --
> I block messages that contain attachments or HTML.
>
>
>
>
>
> >
--~--~---------~--~----~------------~-------~--~----~
To post to this group, send email to NavList@fer3.com
To , send email to NavList-@fer3.com
-~----------~----~----~----~------~----~------~--~---
