NavList:

One note: in this era, and even more so a few decades earlier, it was not unusual to quote angles to seconds. This by itself does not indicate fraud since it does not imply accuracy of seconds. If you wanted to specify any angle less than a minute of arc, seconds were considered the normal option. Fastidious navigators worked everything out to seconds of arc because they believed that this was "correct procedure". The distinction between accuracy and precision was not widely understood and rarely practiced in that time period. Of course in reality, the accuracy of their sights could not have been better than 5 or 10 minutes of arc or possibly much worse, due the likelihood of unusual refraction for low altitudes which Brad and Hewitt already mentioned and also the simple fact that he was using a bubble horizon from a bouncing aircraft.

Hewitt asked if this had been discussed before. The first reference to Byrd in NavList messages that I can find was in a passing reference in a post back in October 2002 by Robert Eno in a thread on Astro Compass History. Five years and a few days later, Gary LaPook also mentioned Byrd in the same context.

In May 2009, Bill Morris described his restoration of a sextant of a type similar to the one used by Byrd. It's a marine sextant with a bubble attachment. He included a photo of his restored instrument:
http://fer3.com/arc/m2.aspx/g8452

In March, 2010 Peter Fogg quoted from a book review which said "Byrd ... claimed to be the first to fly over the North Pole but almost cer­tainly didn't, faking his navigation observations. His pilot, Bernt Balchen, was once asked why Byrd was blocking his career and replied: "Because he didn't fly over the North Pole and he knows I know it." Balchen then detailed statistics showing that Byrd, worried about oil leaking from one of the engines of the Fokker Trimotor, turned back 190 kilometers from the Pole and fudged his figures."

In early 2010 and with follow-ups a year later, there were a few references to Byrd's sextant in a thread on zeppelin navigation:
http://www.fer3.com/arc/sort2.aspx?y=201001&y2=201112&subject=zep
In this thread, there is a short video posted by Gary showing Byrd using his bubble sextant: http://fer3.com/arc/m2.aspx/g15807

-FER

----------------------------------------------------------------
NavList message boards and member settings: www.fer3.com/NavList
Members may optionally receive posts by email.
To cancel email delivery, send a message to NoMail[at]fer3.com
----------------------------------------------------------------