Modern Cable Layers

Nauticapedia
25th April 2012, 20:21
In "the old days" cable layers carried cables on big internal storage holds - and paid it out along the route. Is that how the cable is carried in modern cable ships? How is it stowed now - how do they get it on board - is it still created in one big length of cable or are there splices?

tyneboy
5th May 2012, 18:25
Hi John
I have worked on quite a few cableship designs in my time. It took a long time to understand how they work. The cable now is all fibre optics and yes it is usually in one length. Every few miles of cable have a repeater fitted which boosts the signal. There is a method of joining lengths of cable but this is usaully kept to a minimum as its a bit tricky and can effect the efficiency of the signal

chadburn
5th May 2012, 18:35
In "the old days" cable layers carried cables on big internal storage holds - and paid it out along the route. Is that how the cable is carried in modern cable ships? How is it stowed now - how do they get it on board - is it still created in one big length of cable or are there splices?

Depend's on the design of the Vessel, some put it over the Stern from a large "vertical" drum, other's have the Cable stored in the way you mention and take it out via the "Moonpool".

Mad Landsman
5th May 2012, 19:36
Have a look at this one:

http://www.youtube.com/watch?v=BLyO2597VWs

Documentary featuring: Tyco Resolute.
I remember seeing it on 'Quest' and discovered that it is on YouTube.

RayJordandpo
9th May 2012, 00:01
Hi John
I have worked on quite a few cableship designs in my time. It took a long time to understand how they work. The cable now is all fibre optics and yes it is usually in one length. Every few miles of cable have a repeater fitted which boosts the signal. There is a method of joining lengths of cable but this is usaully kept to a minimum as its a bit tricky and can effect the efficiency of the signal

I served as a deck officer on a couple of cable laying vessels chartered by cable and wireless. You are quite correct about the repeaters and avoiding joining fibre optic cable unless absolutely necessary (although it is sometimes unavoidable when the cable gets severed, i.e. fishing vessels etc.) I remember when we loaded the cable, it was literally wound round massive drums in the cable holds and played havoc with the magnetic compass. It also screwed up wrist watches worn by the loading gangs and a few claims went in (needless to say Timexes and Seikos became Rolexes and Omegas) I also believe that a notice was supposed to be placed at the bottom of the gangway stating that anyone with a heart pacemaker should not board the vessel whilst cable was being loaded but I can't recall seeing such a notice. I was very surprised at the speed we steamed at when laying the cable, sometimes full speed (14 knots plus) and only slowing down when the repeaters went overboard. This was in the eighties so things may well have changed by now.

tyneboy
9th May 2012, 10:19
I think that the reason that there was so much interference was that the cable had to have a charge passing through it at all times as a check that it was not damaged. A lot of the cable ships had ploughs to bury the cable when it was being layed in fishing areas etc. I am a bit surprised at the laying speed as I thought the maximum was about 6 knots.

chadburn
9th May 2012, 12:27
Thinking about Ray's words about claiming for Watch(s). Anyone remember the all Black Watch that Clive Sinclair marketed?, this was one of the first digital watches and the case was made out of plastic, it was advertised as the Watch of the future and I amongst other's fell for the patter and bought one, they were not cheap. It was amazing how fast a couple of hour's could pass whilst wearing this watch.(Jester) They were all recalled it must have cost Sinclair a fortune.

Dave Woods
9th May 2012, 21:23
To answer your first question the cable is coiled into large tanks the same as it always has been and paid out over the stern these days, although I see you have the Global Sentinel at the Ogden Point cable depot. (I spent a few years on Cable Venture, Cable Enterprise and Seaspread sat alongside there, and we left a lot of lonely ladies when we departed!) I believe that she was the last cable ship built with both Bow and Stern cable working capabilities (I stand to be corrected but the new generation cable ships from 1993 were all stern working much to the annoyance of many of the older Captains). It was normal to lay over the stern and repair over the bow, however I have seen both repair and lay over the bow and stern. The laying speed was normally about 8 knots or less, I certainly would not like to see a cable come out of the tank at anything over that especially light- weight which tends to “whip” around the cone.
The modern Fibre cables come out of the factory in one length, complete with “Repeaters” (actually they are called “Optical Amplifiers” these days) every 50 to 70Km apart. It is not uncommon to have a couple of joints in each section due to the fact that different types of fibre are used to correct for Chromatic Dispersion.
When loading the cable systems it is normal to “power up” the cable once or twice a day to check that the cable being loaded has not been damaged. When laying it is quite normal to have the power on all the time except when an amplifier is being launched; this checks that there are no flaws in the “plastic” sheath around the Fibre package allowing ingress of sea water and also the amplifiers have not been damaged during launch. When the cable is powered it is like having an electro magnet in each hold and can affect the magnetic compass, watches etc; it also affects the radars and TV’s / data monitors to some degree. Powering up and down has to be in a controlled manner; preferably quite slowly as the consequences of a sudden power down can be quite catastrophic. I remember a cable lay from Singapore to Japan when shortly after starting to lay off Singapore the power feed failed and the collapsing magnetic flux took out the computer chip in the interswitch to the two radars, thus making them inoperable until we had wired out the unit; it also damaged many of the ships computers. These days there is warning notices at the gangway and in the joining information regarding Heart Pacemakers and the detrimental effects of the magnetic field that is caused by powering the cable.

RayJordandpo
10th May 2012, 16:28
Regarding the speed when laying fibre optic cable. I remember in open water we sometimes ran at full speed which was certainly often more than ten knots, I'm sure it was about fourteen knots. I was working for Denholms at the time and we had a Cable and Wireless crew onboard who ran the show(they eventually took over the manning). There was one Captain who's father was a test pilot for British Airways. He was a great guy and nothing fazed him, even when we forgot to slow down for a repeater going over the stern. There was also a giant Fijian bosun who had worked for C&W for years. Pity I can't remember their names.

Dave Woods
10th May 2012, 16:47
Regarding the speed when laying fibre optic cable. I remember in open water we sometimes ran at full speed which was certainly often more than ten knots, I'm sure it was about fourteen knots. I was working for Denholms at the time and we had a Cable and Wireless crew onboard who ran the show(they eventually took over the manning). There was one Captain who's father was a test pilot for British Airways. He was a great guy and nothing fazed him, even when we forgot to slow down for a repeater going over the stern. There was also a giant Fijian bosun who had worked for C&W for years. Pity I can't remember their names.

That would be Ammoy, he is still around working for "red penguin" I believe.

George Rollinson
10th May 2012, 17:26
Dave,

You beat me to a reply. Amoi was the Bosun. The Captain was Peter Worral. Bright ginger hair and lived in Vigo.

As for the speed 14 knots would normally be considered as a "runaway". Not sure what Denholm ship you were on Ray. C&W used a couple. The Flexservice 3, which they later bought, and the Northern Installer. The speed would have been Km/Hour not knots. I have laid lightweight cable on the Flex 3 at 13 kph and the 4 metre drum was wizzing around. You needed to have your wits about you at that speed! Our normal speed would have been 10-11 kph. The Northern Installer had a 18 wheel pair linear engine and its top speed would not be anywhere near 14 knots.
The best passage speed I ever achieved on the Flex 3 was an average of 12.5 knots from Port Botany to Manila shortly after a docking.

Regards

George Rollinson

Dave Woods
10th May 2012, 19:28
George,

Greetings it’s been a long time. I think you will find a couple of old friends here http://www.redpenguinltd.com/company-profile.html

I quite agree with you about the speed of payout, watching it whip around the cone on inside turns can be quite frightening, especially the stories of it over whipping and pulling the cone out. (Probably not true with light weight but possible with armour!)

Best regards

Dave.

RayJordandpo
10th May 2012, 19:38
Dave,

You beat me to a reply. Amoi was the Bosun. The Captain was Peter Worral. Bright ginger hair and lived in Vigo.

As for the speed 14 knots would normally be considered as a "runaway". Not sure what Denholm ship you were on Ray. C&W used a couple. The Flexservice 3, which they later bought, and the Northern Installer. The speed would have been Km/Hour not knots. I have laid lightweight cable on the Flex 3 at 13 kph and the 4 metre drum was wizzing around. You needed to have your wits about you at that speed! Our normal speed would have been 10-11 kph. The Northern Installer had a 18 wheel pair linear engine and its top speed would not be anywhere near 14 knots.
The best passage speed I ever achieved on the Flex 3 was an average of 12.5 knots from Port Botany to Manila shortly after a docking.

Regards

George Rollinson

You are correct on all accounts. Peter Worral was the Captain (rugby mad) and the ships were the Northern Installer and Flexservice 3.
Guess I must be having a senior moment regarding the speed