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US Navy going to teach celestial navigation

4K views 26 replies 17 participants last post by  hellosailor 
#1 ·
#4 · (Edited)
Let me tell you a true story:

I was servicing on a US nuclear submarine in about 1985. We were part of a NATO exercise and were suppose to be the bad guy and attack the fleet as it made its' way from the US over to the North Sea. Due to a few mechanical problems we left late and were in a maximum catch up to them mode. This means we were basically staying deep and going as fast as were could.

While underway we lost our 400-Hz power system that powered the nav equipment like the gyro/sonar/radar etc, which means basically we were now blind. The standard operating procedure for this was that we had to surface. So we slow down and come up to near the surface. But prior to fully surfacing we need to look around to be sure there's not a ship etc over us. So we turn to starboard and look though the periscope and then turn to port and look again; and once we know we are clear we surface.

We then get our 400-Hz power system back up. But we don't know where we are or which direction we are pointed in order to reset our position on the gyro etc. This is before GPS and the method of confirming your position was to wait for a NavSat to come over to get a position fix off it. But the next NavSat isn't going to be over us for hours and we are getting further behind the fleet.

So since we are in the middle of the ocean and there is nothing to hit while down deep under water, all we need to do is keep heading in the general direction (North in this case) in order to make some progress in catching back up to the fleet. So the Radio Officer takes a star position for North and we dive down deep and go back to running fast.

4 hours later we slow down and come up to periscope depth to take a fix off the NavSat to confirm our position etc. That's when we find out that instead of heading North we have been going South and are further away that when we started. Because apparently that wasn't the North Star that we took a fix off of.

That's my real life story of a multi-billion dollar nuclear attack submarine being lost at sea and why some training in celestial navigation may be useful training today, even on a submarine.


There's more to the story, but for this topic the above is the useful parts.
 
#10 ·
The is probably due to the newer Russian technology that shuts down essentially all electronic gizmos on US warships, such as Aegis defense systems, etc. Apparently, these are aircraft, etc. borne electronic jamming systems; as apparently was used against US warships in the Black Sea recently .... and turned off most of the vital electronic systems on board. If your electronics are shut down, its either big balls of string, bread crumbs or eyeball celestial navigation.
Code Named- "Khibiny" is the newest complex radioelectronic jamming of the Russkies. The USN has no current answer nor countermeasures.

Ref.: AEGIS Fail in Black SEA, Ruskies Burn Down USS Donald ?Duck? | Veterans Today
Do websearch: Khibiny
 
#17 ·
It's actually due to some recent research that was done on GPS signal interference. If you're within reasonable range of a victim, you can simply override the GPS signals, and make the GPS receiver thing it's wherever you want it to be. THis has been demonstrated publicly, and it's rumored that's how Iran captured that US drone a bit ago. (Presumably anything that was emitting radio signals nearby in a war would be immediately vaporized by any reasonable warship, but ¯\_(ツ)_/¯ )
 
#18 ·
GPS spoofing has been discussed, openly, for a long time. I think it was 15 years ago that 2600 magazine (a hackerzine) went into the details of how to build a spoofer. And as recently as two years ago, eBay was full of ads from China for GPS jammers. A NJ trucker who didn't like his employer's tracking software was arrested for using one, after his regular passes by Newark airport were tracked down to him. The airport apparently got tired of GPSes going on the fritz.
So, jamming or spoofing, either one is actually available off the shelf with old cheap technology. However, as 2600 pointed out so many years ago, the military has a fine inventory of what are generally called "anti-radiation missiles". These are most commonly used to fly into a anti-aircraft radar controller and blow it into confetti. But that same technology works equally well with GPS "transmitters", whether they are spoofing or jamming.
You turn it on once, and you can get away with spoofing. As long as no one has been waiting or watching for you, in which case the problem can be quickly eliminated.

One of those cat-and-mouse games that DHS and DoD would prefer not to discuss with the public, for obvious reasons.

IIRC, even after the USNA dropped the "requirement" for celestial nav, they kept the (Plath? Cassens & Plath?) sextants onboard the 44's (?) and still encouraged the cadets to get familiar with them.
 
#19 ·
I would think that if the navy was serious about relying on celestial for navigation they would contract to have a star finder instrument built. Space probes use such a thing. If would be fast and accurate. It could also work in daylight and in limited visibility. Also, taking celestial shots from the steady deck of a ship with a computer and comfortable desk for performing the calculations is vastly simpler than what we small boat sailors must contend with.
 
#20 ·
"I would think that if the navy was serious about relying on celestial for navigation they would contract to have a star finder instrument built."
Not necessary. The Air Force already did this, IIRC for the Blackbirds. The "ball" could actually find and fix navigational stars, even in broad daylight. They did this because the Blackbirds had not room for a navigator, unlike the B-52s, which did have a navigation "bubble" and did use special sextants (rarely found as surplus now) until someone decided that in-flight refueling and bubbles didn't mix, at which point they went back to putting in a flat metal plate on the fuselage.

The equipment is out there, but it was and would still be damned expensive.

Once upon a time, submarines used big expensive 3-D inertial guidance systems with things like ring accelerometers in them. Now? That's a chip on a $5 sub-assembly in every smartphone. Much cheaper to use 3d accelerometers to guide the ship while, when, or if the GPS goes down.
 
#21 · (Edited)
Priorities should be sunlines. LAN and running fixes for morning, noon and evening sites. The rest can come later. This body is used most of the time--not stars or planets. Plus it works on all platforms, from the smallest to the largest. Sailboats or ships. In the US Coast Guard, we used the sun 90% of the time with great results. Stars and planet if you can get them, but more prone to error unless you use an astigmatizer lens fitted to the group of index shades.
 
#22 · (Edited)
Yup. And, if you know what you're doing, you can obtain a FIX (both Lat and Lon) around noon by taking: (1) the normal "noon shot" at meridian passage for latitude; and (2) several sights before and after Local Apparent Noon (LAN) for longitude. These latter sights for longitude don't require any correction, just simple math.

And, none of these sights require sight reduction tables. Only need access to a nautical almanac, paper or electronic.

This is the method I've used at sea and have taught in celestial nav classes. Simple, clean, quick, and effective.

Bill
 
#23 ·
Crossing over to Caribe back before there as an ARC that was our chosen and only known to us method. About a week before Barbadoes it clouded over and when an island should have shown I used my little transistor radio. Found it was either to port or starboard (180??) Chose port and ended in Tobago.34 days from GCanary. Just sailing ,never lost.
 
#25 ·
Yes, I have the iNA app for the iPad and iPhone. For practice it saves having to buy the book every year. It is good because its output is much like the book.

I wouldn't rely on any electronic gizmos for my at-sea celestial because the main reason is to be independent of as many systems as possible: Sextant, watch, almanac, pencil.
 
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#27 ·
The sight reduction apps (for Palm, iOs, Android, Windows) have been rock solid for twenty years now. The platform you run them on is the frail part. An antique Palm PDA that has no other job, no internet connections, and runs on two AAA cells for four months without losing the programs if those die, has something to be said for it. (Also fits in the sextant case, where it belongs.(G)
 
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