NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Fairchild A-10
From: Gary LaPook
Date: 2017 Jul 2, 22:03 +0000
From: David Pike <NoReply_DavidPike@fer3.com>
To: garylapook@pacbell.net
Sent: Sunday, July 2, 2017 2:05 PM
Subject: [NavList] Re: Fairchild A-10
From: Gary LaPook
Date: 2017 Jul 2, 22:03 +0000
The A-10 has a little lever that you push the make a pencil mark on the averger disk. So when you are looking through the sight and the object is inside the bubble you push the lever and make that mark. Do it for 2 minutes and then rotate the altitude knob until the pencil lead is at the median of all the pencil marks and read out the averaged or actually the median of all the observations.
The A-10A added a a very primitive escapement that sent a pulse to a relay which then sent a pulse to a solenoid that pushed that pencil lead to make a mark on the disk. In use you hold down a trigger and the averager sends a pulse every second to the solenoid so 120 marks in two minutes. Then center the marks agains the pencil lead and read out the altitude.. There is a 4.5 volt, three "D" cell battery holder that you connect to the sextant to run the lighting for the bubble an the light for the scale and also the averager mechanism.
gl
From: David Pike <NoReply_DavidPike@fer3.com>
To: garylapook@pacbell.net
Sent: Sunday, July 2, 2017 2:05 PM
Subject: [NavList] Re: Fairchild A-10
The guts are the same the A model just has a clockwork activated solenoid that pushes the pencil averager every second. gl
So that’s how it works; power required; I just thought mine was jammed. So faced with 60 or so pencil marks over a large or small sector of a circle, what did they do next? DaveP
