What happens to British ships when satellites don't work?

[papasmurf]

Now you surprise me.


I knew it WAS but that was back in the mid 90s....

I will have to as my neighbour, (retired lifeboat coxaswain,) I think he had to do the exam/test, as did some local fishing boat skippers but they are on large fishing boats.

[johnofgwent]

It is part of Yachtmasters and similar certification.

Now you surprise me.

I knew it WAS but that was back in the mid 90s.....

[papasmurf]

Such skills are sadly lost in the amateur boating generation.

It is part of Yachtmasters and similar certification.

[johnofgwent]

It is sometime since I sweated over Norie's six figure log tables, but I seem to recall that we had sextants for the latitude and chronometers for the longitude. I can also recall bobbing up and down on an oil tanker in the middle of the Pacific, shit faced drunk for three days over the Christmas with no real idea where we were.

Indeed you did.


The half silvered mirror allowed you to bring the sun to the horizon and calculate both the latitude you had sailed to, AND know the time of local noon (sun high point in the sky) giving you the highest reading of the day...


By logging the sextants readings at intervals until you knew the one with the highest elevation today, when you did know that, you used the time on the ships chronometer set to Greenwich to work out the latitude (crudely the time zone then subdivide).


Such skills are sadly lost in the amateur boating generation.


GPS did not help you at Christmas in the Pacific


I got an irate call in a satellite phone from my uncle. It went along the lines of "I thought you were putting up a fucking GPS" and my equally robust "I fucking have" was met with "come tell the king of fucking Tonga that mybdhips got no fucking idea where it is and the King of Tonga wants his wonga"


At Christmas, earth pulls the equivalent of a right hander round marble arch as it whips round the irregular bit of its orbit. The geostationary satellites become not so geostationary and the gps signal fails. Inmarsat birds try tomcompensate with extra beams but Tonga is awkwardly placed between two birds and the signals interfere


This is the other reason i mock the story. It happens twice yearly already at apogee / perigee and ships just keep on sailing.... Or not

[johnofgwent]

Indeed though when it got misty it was useless and they had to get Tony Curtis to find the way with a little fishy thing on a bit of string

That man and his bloody horny hat have much to answer for
And Kirk bloody Douglas ....

[Borchester]

What happens to British ships when satellites don't work?

The Royal Navy and merchant fleet have no back-up if navigation systems are disrupted, experts warn.

Source: What happens to British ships when satellites don't work?

It is sometime since I sweated over Norie's six figure log tables, but I seem to recall that we had sextants for the latitude and chronometers for the longitude. I can also recall bobbing up and down on an oil tanker in the middle of the Pacific, shit faced drunk for three days over the Christmas with no real idea where we were.

[Streetwalker]

Actually I didn't, the Vikings used something very similar to that and navigated accurately with it.

Indeed though when it got misty it was useless and they had to get Tony Curtis to find the way with a little fishy thing on a bit of string

[papasmurf]

And much as I suspect our resident of Cornwall put that post up as a piss take,

Actually I didn't, the Vikings used something very similar to that and navigated accurately with it.

[johnofgwent]

The INMARSAT geostationary satellites provide the necessary reference signal and have done for years. Inmarsat was very much a British company when I helped it put its data carrier service up, and boy did we piss off the yanks when we "returned the favour" and painted the high accuracy signal all over the USA like they did to us with their low orbital birds.


We do not rely on the low orbit "cellular" gps satellites any more.


And much as I suspect our resident of Cornwall put that post up as a piss take, to be honest any bridge officer unable to use a sextant and a ships chronometer to work out where the hell the ship is without GPS is unfit to wear the uniform.


There are alternatives and always have been. That they are not as easy to use, or as accurate, as GPS is not the fault of the GPS system ....

[papasmurf]

[GBNews]

What happens to British ships when satellites don't work?

The Royal Navy and merchant fleet have no back-up if navigation systems are disrupted, experts warn.

Source: What happens to British ships when satellites don't work?