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Subject: Re: book on Modified H.O. 211
From: Joe Shields (jshields@XXX.XXX)
Date: Wed Sep 01 1999 - 10:06:41 EDT
For 6 bucks it is a steal! The book is 32 pages, but the actual table will
fit on very few 8.5 x 11 sheets of paper (xeroxed) so you can have an
unlimited number of backup copies stuffed inside the sextant case, in a life
raft, etc.
I have a copy of the original 1940's H.O. 211 with thumbnail indexes, but it
took me so long to obtain it and it is so old now, that it is sort of
collector's status for me, and I don't like to get it dirty.... so I have
gotten used to using Bayless' compact H.O. 211 table. I think once I got
accustomed to it, it actually became faster than using the original H.O. 211
because there are fewer pages to flip through. You do have to be careful to
make sure you are using an A col. or B col., but that is automatic for me
now.
Since purchasing a GPS for $100, I have been re-thinking Celestial Nav. as a
practical emergency backup. Celestial is a volatile skill that needs to be
practiced regularly to be of use. In the worst scenario (boat sinks -
you're on a small life raft in the middle of the ocean - no electricity, no
electronics) do you really want all the weight of H.O. 229 or 249 sloshing
around? Yet if that is what you use regularly, will you be able to pick up
H.O. 211 quickly enough to maybe send a position before the radio goes out?
I've put together a little booklet containing the H.O. 211 table pages from
Bayless, and the one page concise Sun almanac table from the instruction
manual that came with my Davis Mark III sextant. Just using that booklet
(it also contains the one page arc-to-time table and the Refraction
correction tables from a 1993 Nautical Almanac) and the plastic sextant, I
can consistently get within 10' of what my GPS says. By interpolating the
Sun's position instead of just using the daily figures for Declination and
Eq. of T. I can get even closer. That is enough of a reassuring check on
what the GPS is saying, plus provides practice time for worst scenario
disaster so that my backup method is comfortable. I can reduce a shot in 5
minutes, and everything I need is in one case (paper and pencils and back up
watch with known error rate included).
So for me Bayless is great!
-- Joe
> ----------
> From: Russell Sher[SMTP:rsher@XXX.XXX]
> Reply To: Navigation Mailing List
> Sent: Wednesday, September 01, 1999 3:17 AM
> To: NAVIGATION-L@XXX.XXX
> Subject: book on Modified H.O. 211
>
> Hi - does anyone know about the book 'COMPACT SIGHT REDUCTION TABLE:
> Modified H.O. 211, Ageton's Table'?
> (by Allan E. Bayless)
> In particular, I am interested in obtaining opinions by anyone who has
> used
> it and recommends obtaining it.
>
> Regards
> Russell
>
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