Navigation without radar


yla

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Dec 15, 2019
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Hi I have a question,

How did the officers steer the ship to new York and back to England without radar?.

Yes I knew titanic never made it to NY but her bow is sitting on the ocean floor facing NY. Not only that, prior and after titanic, ships made the transatlatic route the same way-no radar and never got lost.

I find it amazing how officers don't get lost but they find thier way across the atalantic without any form Of navigation apart from thier own skills.

Could todays officers take a ship to NY from south Hampton without radar? I. Don't think so.

I have probably placed thread in the wrong section but didn't know where to place this thread.. Sorry.
 
May 3, 2005
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Hi I have a question,

How did the officers steer the ship to new York and back to England without radar?.

Yes I knew titanic never made it to NY but her bow is sitting on the ocean floor facing NY. Not only that, prior and after titanic, ships made the transatlati c route the same way-no radar and never got lost.

I find it amazing how officers don't get lost but they find thier way across the atalantic without any form Of navigation apart from thier own skills.

Could todays officers take a ship to NY from south Hampton without radar? I. Don't think so.

I have probably placed thread in the wrong section but didn't know where to place this thread.. Sorry. Have
It has been my observation that ships do not need radar to navigate across the Atlantic.
However, the radar was used as a lookout to continually provide a picture of the area around the ship to avoid collisions with ships in its path.

The range, or limits of the maximum distance that some surface search radars have, is governed by the distance the radar can "see" to the horizon, which could be less than 10 or 15 miles for some radar systems.

Jim Currie or Samuel Halpern could give you a better explanation of how ships navigate across the ocean without radar. Do. ships still rely on observations with sextants to navigate
and determinate their locations when crossing oceans such as the Atlantic or has this been replaced by modern electronic aids to navigation such as GPS ?

Am I correct in assuming the surface search radar has replaced the man who was the Lookout in the Crow's Nest ?
 
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May 3, 2005
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Sam -
As a former radar technician I believe I am on solid ground when I say radar is never used to plot your course from one point to another across any ocean whether it be the Atlantic or the Pacific.

And as a former radar technician I would be completely out of my bounds in knowing the methods in plotting the course from Queenstown to New York. I would have to do a little more than "simple research" on that subject.

That's why I know I keep harping that even though I did serve a short period of Sea Duty in the U.S. Navy I would never consider myself a formerMariner or even a Sailor. LOL

Cheers and thanks for all the interesting information you supply !

Robert

P.S. I only had one assignment on Shore Patrol and I wouldn't consider myself as a former Policeman . LOL


And South Hampton is in the US and Southampton is in the UK.
There is a Southampton, NY......listed as being in a high crime area. :-(
 
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T Gerard

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Feb 26, 2019
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I wonder if you mean GPS instead of radar. Up until fairly recently in maritime history you'd navigate using the sun by day and stars by night, using a tool called a sextant, and combine that with using your compass and paper charts. You could then use a method called dead reckoning to estimate your current position based on time since your last known position and speed you've been traveling. I have several friends/classmates with their US Coast Guard deck license who have told me that, even today with all the modern technology, they still have to know celestial navigation, in case all the electronics fail.
 

Georges G.

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Feb 26, 2017
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You can transfer in a few seconds all the way points joining a route, from the GPS to the Radar. So then, you can follow the track shown on the Radar PPI and cross the Atlantic sitting on the chair while smoking a cigar.
 
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May 3, 2005
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Do we have any old U.S. Navy veterans of the Dinosaur Age, such as maybe 50 or 60 years ago who are still alive and on these forums ? Or any recent active persons ?
I'm just curious if daily sextant readings are or were made on Navy ships , especially on crossings from San Diego to Honolulu for example.

During my Naval service I never had occasion to go on the Bridge except to check the radar PPI's , etc. , so I am completely ignorant of the methods they used to keep track of the location of the ship at all times. I would be interested in knowing if this was done by the sextant readings, dead reckoning , etc.or other means ? *

I have an old GPS, a " Netropa Intellinav 2" several years old now. It still shows me exactly where I am on the streets and highways of my route. I would suppose you might consider it the equivalent of a Radar PPI tracking your route ?

* This is what I mean by being a "Specialist", but never a "Sailor". LOL.

Georges G :
What would you do when you are sitting in that chair when " The smoking lamp is out" ? LOL
 
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Georges G.

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You just lit up another cigar …

The Global Positioning System (GPS) is composed of 24 to 32 satellites, the Global Navigation Satellite System (GLONASS) is composed of 24 satellites that provides an alternative to GPS with global coverage of comparable precision and Galileo, a global system being developed by the European Union and other partner countries, that is expected to be fully deployed by 2020.

How many of these satellites do you really need to have an acceptable fix. I sailed across the oceans on a VLCC in 1991, years before the system was declare operational, but our GPS was still giving good services.

So it is not tomorrow that will get lost on the ocean. The problem doesn’t actuality rely on GPS, but rather on its overreliance. Say you lose GPS; you still have excellent Pilot Charts for dead reckoning navigation, Loch for speed over the water, Radar for coastal approaches, Gyro for accurate headings and bearings, Depth Sounder for bathymetric lines. I crossed oceans by sextant alone. It’s good but absolutely necessary, it’s another debate …
 
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You just lit up another cigar …

The Global Positioning System (GPS) is composed of 24 to 32 satellites, the Global Navigation Satellite System (GLONASS) is composed of 24 satellites that provides an alternative to GPS with global coverage of comparable precision and Galileo, a global system being developed by the European Union and other partner countries, that is expected to be fully deployed by 2020.

How many of these satellites do you really need to have an acceptable fix. I sailed across the oceans on a VLCC in 1991, years before the system was declare operational, but our GPS was still giving good services.

So it is not tomorrow that will get lost on the ocean. The problem doesn’t actuality rely on GPS, but rather on its overreliance. Say you lose GPS; you still have excellent Pilot Charts for dead reckoning navigation, Loch for speed over the water, Radar for coastal approaches, Gyro for accurate headings and bearings, Depth Sounder for bathymetric lines. I crossed oceans by sextant alone. It’s good but absolutely necessary, it’s another debate …
Of course I am not knowledgeable about modern ships GPS.
But on my old Intellinav 2 GPS usually 12 satellites are shown and you have to get 3 out of 12 for a fix.
 

Georges G.

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Robert, just to give you an idea where navigation technology stands today, Titanic would be equipped with two certified and approved ECDIS (Electronic Chart Display and Information System), downloaded by S-57 Vector Charts (or by S-100 Real Time Bathymetric Vector Charts) which would authorize the vessel to sail with no paper charts. The ECDIS would be feed by two independent DGPS WAAS (Differential Global Positioning System) (Wide Area Augmentation System). The ECDIS would be interface by the Gyro Compass, a Satellite Compass, a Magnetic Compass, an AIS (Automatic Identification System), an overlay Digital Arpa Radar 3cm or 10cm, an Auto Tracking, a Rudder Indicator, a Rate of Turn Indicator, a Course Projector, a Pilot Auto Track, a Course recorder, a Doppler Water & Ground Speed Log, a Depth Sounder, a Wind Vane Direction/Speed Indicator, all kinds of alarm settings; guard zones, safety depth contours, course & route off track, etc., etc. All data duly recorded. I will spare you from the Maneuvering and engine Controls!

So on a sea of glass; it would be virtually impossible to hit an iceberg. But on rough seas, a small berg could become undetected, hidden by crest waves Radar return. Growlers are still quite impossible to detect by nighttime, by reduce visibility or by adverse weather. They still inflict serious damages, but nothing that could sink a liner of that type…
 
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Georges G.

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I know nothing about Sonar. But I found that on the net; «We tested the range of the sonar by looking at a solid concrete wall. The wall was clearly visible at ranges just over 300 feet». At 22½ knots you would detect an iceberg in less than 8 seconds before impact … I should’ve said in 8 seconds too late !!!
 
May 3, 2005
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I would have to do a bit of research, but I have heard that radar is not very effective on icebergs.
But since most of the iceberg is below the water - 7/8 of an iceberg is below the water - this would be a big Target for the Sonar - a big solid subject like a submarine.
Just another idea.

The ship on which I served just sailed on the Pacific during late Spring to early Fall so I have no experience with icebergs and this is all speculations..
 

Georges G.

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«In the last 25 years there have been 57 collisions with icebergs in the northern hemisphere for all vessel types (the very vast majority being Fishing Trawlers) giving a rate of 2.3 per year, or a little over one per year in the Strait of Belle Isle – Grand Banks area. An estimate of the annual number of cargo ships over the Grand Banks was made, and from that a probability of an iceberg collision of 0.05% was derived, or one collision for every 2000 cargo vessel voyages.»

In the spring time when the ice coverage permits ice classed container vessels to proceed safely via the Strait of Belle Isle, they meet up to 125 icebergs per passage. You would certainly increase the 0.05% collision probability if the detection by Radar was not efficient. Again, most damages are due to Bergy Bitts Icebergs or Growlers that would certainly not sink an ocean liner. Anyhow, I don’t really see how a Sonar transducer could be installed at the stem of a vessel, where it could be crushed not only by Growlers but by all kinds of very hard field ice of all years and thickness.
 

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