A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Quartz article: reinstating celestial...
From: Lu Abel
Date: 2015 Oct 22, 17:24 +0000
From: Lu Abel
Date: 2015 Oct 22, 17:24 +0000
As of right now, there are three different fully operational worldwide satellite navigation systems -- GPS, Glosnass, and Beidou. Plus there are three others (Europe's not-quite-in-service) Galileo, and partial coverage systems fielded by Japan and India. So if some hypothetical adversary "took out" GPS, there would still be several other systems from which positional information could be obtained.
I have no explicit knowledge of this, but it also seems to me that warships might have inertial navigation systems as backup to GPS. US submarines stay underwater (and therefore out of GPS's reach) for long periods of time and it's claimed that their INS's are amazingly accurate.
As a total aside, I have a colleague who claims his new iPhone displays Glosnass location data as well as GPS data. I asked him about how to get the display and he says "my phone just came that way" Does anyone have insight into this?
From: Paul Dolkas <NoReply_Dolkas@fer3.com>
Sent: Wednesday, October 21, 2015 5:17 PM
Subject: [NavList] Re: Quartz article: reinstating celestial...
I might have missed something, but it seems obvious to me why the Navy is reinstating having it’s cadets have a basic working knowledge of CN. If I were an adversary, the first thing I would want to do if trying to mess up our defense capability is to try and take out as much of the satellite infrastructure that our armed forces depend on. Navigation and communication. So it makes sense that we retain CN as a worst-case backup, should something like this occur.But guys, get serious. There’s no reason, in this day and age, for resorting to pencil & paper arithmetic, when there are calculators and cell phone apps that do the same thing. Just because the GPS satellites could be disabled doesn’t mean that the CN calculators go belly up at the same time. We are talking about two independent technologies. I applaud the Navy for re-instating CN. But this is the 21st century for God’s sakes. Let’s stop pretending we are back in the days of wooden ships and sails.Paul DolkasFrom: NavList@fer3.com [mailto:NavList@fer3.com] On Behalf Of Lu Abel
Sent: Wednesday, October 21, 2015 12:07 PM
Subject: [NavList] Re: Quartz article: reinstating celestial...Excellent insights as usual, Frank.If it wasn't apparent from my inquiry about the sight reduction methods that would be used for the USNA course I, too, was wondering what sort of scenario would lead to a practical need for celestial.For example, in a reply to my post Robert Eno suggested that the midshipmen wold be doing LOC reductions using a scientific calculator. But if I look at the guts of a calculator vs a GPS set, they're identical -- a battery, a keyboard, a display, and a chip that provides the functionality. There's no real difference except the functionality embedded in the chip and I can imagine no scenario where only GPS chips are fried.But there's something organic about pre-GPS navigation where awareness of one's surroundings (whether on shore or in the sky) and use of them is the way one obtains a position. Not just some numbers on some electronic display, God-only-knows-how-they-got-there.So, yeah, tradition and awareness -- not necessarily practical needs -- are very likely the motivation for the resumption of teaching Celestial at the US Naval Academy.LuFrom: Frank Reed <NoReply_FrankReed@fer3.com>
Sent: Tuesday, October 20, 2015 6:52 PM
Subject: [NavList] Re: Quartz article: reinstating celestial...Dave Pike, you wrote:
"On celestial being a back-up for loss of GNSS. Unless the USN has a device that can guarantee clear skies at all times, celestial is a pretty unreliable back-up. This leads me back to my original suggestion that this is as much to do with maintaining standards, engendering confidence in tyro navigating officers, and inculcating a strong sense of the traditions of the USN from John Barry and John Paul Jones onwards as with GNSS loss. The obvious short-term replacement for temporary loss of GNSS is SINS or eLoran, if available, and if all else fails, there’s dead-reckoning."I agree with your suggestion about motivations, and I agree with your assessment on the appropriate sequence of replacements for navigation methods. The Naval Academy has an actual semester-length course devoted to USN history. History matters to them. Also, I think it's important to remember that the US Naval Academy is not a "trade school". It endeavors to be a general education institution, not quite liberal arts, but much more broad than what one might expect from a military academy and even more broad than the expectations for an engineering college. They aim to create officers who are ambassadors of a sort for the USA, as well as competent mariners. If you look at the course listings on their web site, it's much more than a school for naval officers. The topic of celestial navigation certainly fits in with the broad aims of education at Annapolis even if there is no expectation of practical value from the subject.I worry that some folks are reading too much into the tea leaves on this story (not here, but particularly in other media coverage). It's just one school, and it's a navigation education program with limited aims. This news tells us next to nothing about navigational practice.Frank Reed
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