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From: Royer, Doug (no email)
Date: Tue Nov 01 2005 - 13:41:32 EST
I wrote:
"There is a 9 page edition of HO-229".
What I meant was that there is a 9 page edition of HO-211.
Bill wrote:
Thanks to you and many others on the list, I have exceeded my initial goal
of 229 reductions, and can now knock off a reduction on a $10, 3-memory
TI-30XA using only the daily pages in less than two minutes. But still so
much more to learn.
Hope you will give 229 a look. Not ideal in strange circumstances, but does
work well for recommended observations. Coupled with an almanac, no
electricity, calculators or computers required (other than generating the
volumes ;-) Pencil and paper only. A great backup to GPS backup. <G>
It also has other tricks to play with the tables, such as star location or
identification, great-circle route calculation, and a table of offsets to
correct the LOP from a long intercept to more closely approximate a COP.
Not as painless as a calculator, but not rocket science either. Heck, even
I can do it!
Bill
"Hope you give 229 a look".
Yes, it's a great tabular method. It also has the ability to to perform
other functions as noted.
When I started out I was taught reduction using HO-208. HO-208 is a little
more tedious to use than is HO-229 but gives real solid results. HO-208 also
is able to perform the same other functions as HO-229.
Because of the number of volumes needed to cover all latitudes by both
HO-208 and HO-229 methods we started using HO-249 vol. I for everyday use.
This is quick and easy to use to reduce data but has drawbacks and only
covers those latitudes used most. Nutation and only 5 stars to chose from
with the 3 best stars noted for a particular LHA. But you can get by
nicely,for the most part,with just 1 volume aboard the vessel. Volumes II
and III cover everything else and have much greater flexibility(as they are
built to use with the same format as HO-229). But,again,one now has multiple
volumes to lug around to be able to cover everything.
I learned and then started to use HO-211 on a regular basis. 28 pages of
data covers just about everything to reduce sights. But that is all it is
capable of doing. It can't compute GC sailings etc. But being able to reduce
98% of all sights anywhere with a 28 page book(including procedures to use
the tables and a work sheet form for reduction using the Ageton Method)this
is a great tool to have and know how to use.
There is now a 9 page HO-229(Ageton)reduction book but I have never tried
it. In older navigation books they usually include the HO-211 reduction
tables in the rear of the book.
In the rear of each year's paper NA there is an interesting method with
tabular reduction tables included. Usually located behind the Polaris tables
and before the conversion of arc to time tables. I'm describing the
reduction tables inside the yearly hardback NA. I'm not sure if the
commercial volume of the NA has these included.
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