NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Rude star finder
From: Gary LaPook
Date: 2015 Dec 17, 18:18 +0000
From: John Brown <NoReply_JohnBrown@fer3.com>
To: garylapook@pacbell.net
Sent: Thursday, December 17, 2015 9:20 AM
Subject: [NavList] Re: Rude star finder
From: Gary LaPook
Date: 2015 Dec 17, 18:18 +0000
Well, as I said, i like the 2102-D, I have three of them plus the updated one with the variable latitude (I'm not going to go and get it now to read it's model number). It is usually used to plan which stars will be available so as to preset the sextant so that a star can be picked out as early after sunset as possible while the horizon is at its best. It is also useful in flight navigation for the same purpose since fixes are taken all night long and the position of the plane changes significantly between fixes. But, if you use HO 249 volume 1 for your star sights (which is its intended purpose) then it provides the information for presetting your sextant and is the way it it used in flight navigation, since the periscopic sextant absolutely needs to be pre-set. On a sailboat the stars up there tonight are the same ones that were there last night so shouldn't be any surprise. If you don't know what star is visible through a hole in the clouds then just shoot it anyway and figure it out later, it's not that hard. If it turns out that you con't then figure out which of the 57 navigational stars you just shot then the HO 2102-D wouldn't have been of any help to you anyway since it only shows those 57 stars. In this case, even if you have a 2102-D, you will have to work it out using the list of 173 stars in the Nautical Almanac.
gl
From: John Brown <NoReply_JohnBrown@fer3.com>
To: garylapook@pacbell.net
Sent: Thursday, December 17, 2015 9:20 AM
Subject: [NavList] Re: Rude star finder
Thanks Henry
An appreciation of the merits of the Rude star finder would seem to fit well with the Navlist mission statement at the head of this page. We don’t spend a lot of time discussing the astrolabe or the back staff, so I suppose that these tools must be classed as archaic rather than traditional. However, we are still here and can testify to the usefulness of 2102-D in real life under fairly normal (i.e. adverse) conditions at sea, particularly in the North Atlantic. It is good to note that this is appreciated by Sean, Alan and others who have different backgrounds, but can muster the essential supporting arguments for Captain Rude’s, no batteries required invention, without much trouble.
The 2102-D was still popular in the 1960s for the reasons you expanded on, in particular the problem of identifying stars through fleeting gaps in the cloud with a brief, time limited usable horizon and no constellations visible. So, a useful and traditional addition to the navigator’s tools, even if it has probably ‘seen its day’ - a bit like the sextant, the lunar distance, nautical astronomy generally and all the other traditional items of interest we share on Navlist.
Regards to all and best wishes for the festive season and 2016!
John
