Celestial Navigators - Sight Reduction Tables Pub 229 v Pub 249

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Over the winter I have been getting my Celestial Navigation up to speed.

I have a few passages planned over the summer that I will have time to do some old fashioned navigation with sextant and universal plotting sheets. Ultimately this is for a RYA Ocean Ticket sometime in the future.

I've been looking at both the Pub 229 - Sight Reduction Tables for Marine Navigation and Pub 249 - Sight Reduction Tables for Air Navigation.

While both publications have the same data with different layouts I would be interested to hear if anybody has a preference or is it just what you are used to?

I am beginning to view 229 as the way to go.
 
It may sound strange - but the Air Nav versions were commonly used on Ships ! For Stars that is.

As for Sun ... it was often down to which Shipping Co you were in ... the 'old hand' Co's like Blue Star / Cunard etc seemed to stick with Long by Chron ... while us Tanker / Bulker guys tended to use Marc St Helaire.
 
Refueler said:
It may sound strange - but the Air Nav versions were commonly used on Ships ! For Stars that is.

As for Sun ... it was often down to which Shipping Co you were in ... the 'old hand' Co's like Blue Star / Cunard etc seemed to stick with Long by Chron ... while us Tanker / Bulker guys tended to use Marc St Helaire.
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Depending who you read/watch on YouTube both are used, hence the question about what others do. Pub 249 Vol 1 will be needed for stars.

As stated in post #1 I am beginning to think that Pub 229 works better for my brain.

Company practice is their choice. I choose to keep UTC onboard and move to Zone Time when I go ashore. While in the UK it means that I don't have to faff about with tide tables and get caught out not adding the hour when we go to BST. When ashore overseas I set my watch's 'other time zone' and revert to UTC when back onboard. I have had a few laughs with people as they swap time zones and get totally confused, e.g. Portugal = WET, Spain = CET, France = CET and UK WET.
 
AP3270 (=Pub249/NP303/Ho249) is my preferred option. Two volumes cover all latitudes with another, Vol 1, for stars. Pub229 consists of 6 volumes so if you're covering a wide range of latitudes then you may need to carry more books (I find it quicker to use the hardcopies) although of course that is irrelevant if you download them.

The word "Rapid" in the title of Pub249 suggests that the process using those tables is quicker but Pub229 yields figures that are of higher precision. I've never found that supposed loss of precision to be an issue. For instance, an Azimuth to the nearest degree rather than the nearest tenth of a degree is fine for me, same with Hc and d.
 
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Our American friends allow free download, of Pub 229 and 249 plus other useful stuff, for the moment. All OH publications are chargeable.

As a Scot I have a reputation to uphold and enjoy my visits to the library to print off the latitudes I need.
 
If you decide that Pub229 is the way you want to go I have a copy of NP401 (Same as Pub229) for latitudes 45° to 60° so good for UK Waters. You are welcome to it at a Scotsman's favourite price if you like. :)
 
S04 said:
If you decide that Pub229 is the way you want to go I have a copy of NP401 (Same as Pub229) for latitudes 45° to 60° so good for UK Waters. You are welcome to it at a Scotsman's favourite price if you like. :)
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Thank you for the kind offer @S04.

I am building an A4 folder with all the paperwork that I need rather than have lots of different books to flick between. I print off the daily pages for when I am sailing and don't need all the 'interesting technical content' at the front of many of the reduction tables. Part of my contribution to reducing the number of trees chopped down for paper.
 
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I seem to remember the RYA course using the air navigation tables, but will check when home. You can get a printed version from Amazon's print on demand service for about a tenner.
 
You can also print on demand a nautical almanac from the free website of the same name on Lulu. It takes a while as for some reason some pages have been produced US letter, but the bulk is A4. So a few pages need resizing.
 
Then there's Reed's Astro Navigation Tables 2025, originated by Lt Cdr Harry Baker and then called 'Reeds Heavenly Bodies'.


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This slim publication has all that was needed for a passage from Liverpool, outside Ireland, to La Coruna using only astro and trad nav.

It's unlikely to be quite as cheap as photocopying pages in a library, or 'borrowing' a copy of His Maj's Air Tables, but an online search shows some sharp prices.
 
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I've also got "Celestial Navigation with the S Table" by Mike Pepperday. A complete sight reduction method for all bodies. In only nine pages!
Works directly from your DR position rather than an assumed position.
 
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