Sunspots: The dangers of over-reliance on GPS

GPS is really handy when practicing those hard earned Day Skipper skills.  If when cruising the GPS shows that your chart work is wrong then it’s easy to see your mistake and work out where you went wrong, or to find someone to set out how to do it, hopefully with no harm done.  But could it be dangerous to rely solely on GPS when navigating?

Caused by huge fluctuations in the magnetic field of our sun, sunspot activity increases and decreases on an 11-year cycle, and predictions are that 2012 will not only be the peak of this sunspot cycle, but also signal the largest increase in solar activity recorded for decades.

Intense sunspot activity brings with it solar storms, emitting waves of particles to bombard our planets’ atmosphere. These storms can cause large disturbances across all sorts of radio transmissions and navigational devices, including your onboard GPS.

With this potentially dangerous series of events only a matter of months away, we begin to think about the potential dangers of relying solely on GPS to navigate a vessel. For those of us who remember navigating BG (before GPS) the danger is all too clear.

“I have experienced GPS failure three times.  Once the wire from the aerial fell off, once the whole system went off line for about 3 hours for no explicable reason (both the yacht’s fixed GPS and a couple of hand-helds did not work) and once the hand held stopped never to work again.  The GPS system also gave erroneous fixes – once 44 miles out in Scotland and once 1,000 yards out in the Dover Strait.” (Bill  – Mustang Sailing)

So Day Skipper: Don’t let those useful skills go rusty. Practice the tidal vectors, practice the 3-point fixes and keep an hourly log of your position and you will be ready for the worst.