A reminder

Let’s not lose our radar range and bearing and celestial navigation skills.


Posted on | February 14, 2011
Every day that passes increases our dependence on the clever satellites of the Global Positioning System.

Seafarers think that their primary role is to help them navigate but in truth, the position of the ship on the surface of the sea is well down the list of GPS priorities.

Telecommunication and internet traffic depends on their precision timing, as do virtually all emergency services. Financial transactions, even the humble cash dispenser and the electronic tills in retail outlets depend upon GPS, just as much as half the equipment in the average hospital. There is scarcely an industry in the developed world that does not depend on these orbiting man-made stars.

Aboard ship, more and more equipment depends on the weak signals transmitted from 20,000 kms out in space. Position-finding equipment, radar, AIS, communication gear, gyro-compasses and computers that offer diagnostic signals are just part of the ship’s outfit that depend upon these radio waves from space. And our vulnerability to any interruption of these useful signals grows constantly.

This perhaps worrying message was given recently by Professor David Last, the immediate past-president of the Royal Institute of Navigation.

Speaking about the “new stars we sail by” at the Royal Society of Edinburgh, Professor Last reminded his listeners of the trials of a GPS signal jammer which was activated at Flamborough Head as the Northern Lighthouse Board tender sailed past in the North Sea.

The result was pandemonium, with virtually every system aboard this exceptionally well-equipped (and well-prepared) ship gave up the ghost in a simultaneous burst of loud alarms. Only the vessel’s enhanced Loran was unaffected by the interruption.

Each of the satellites we depend upon (and there will be some 140 of them out there by 2015 in the competing (or complementary) GPS systems, radiates no more power than a car headlight and can be swamped by man-made radio interference, or the radio noise from solar activity.

The mad, the bad and the terrorist can obtain, over the internet, a pocket-sized jammer that will block signals at a range of 30km from the source. And while not wishing to alarm us unduly, Professor Last also noted that the next solar “maximum”, which happens every 11 years, is expected to affect life here on earth in 2013. It is worth considering our extraordinary growth in dependence upon our friendly satellites since the last solar max, in 2002. That one fried the Canadian telecoms system. We have been warned.