NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: David Pike
Date: 2024 Apr 1, 14:02 -0700
K McGrath
Re Chichester over the Tasman Sea: In many ways you're honoured. It's now generally believed he used a box sextant. His DH Moth with oversized floats would have been almost impossible to fly 'hands off’ for more than a few seconds, so he probably set his box sextant to a pre-calculated Hc and then estimated what fraction of the Moon’s semi-diameter its lower limb was above or below the horizon (beloe means add). He could have done this with a quick glance. Also, if he flew just below 300ft, he could ignore dip. Until the arrival of GNSS, air navigation was never an exact science. Chichester might have advised Hughes & Son a bit; the company liked to entertain and work with famous fliers, but P. F. Everitt was their main designer. DaveP
