Learning the Failure Modes on your GPS/plotting system.
Here are some crucial, but easy to perform tests involving the integrity of the GPS signal
and the resultant change or lack of change in the computer screen.
1. What happens on the computer screen when GPS is turned ON?
1.1 Normally it takes 15 seconds to get valid signals.
Does your GPS ON indicator turn on instantly?
1.2 What happens when the GPS never gets past the
Acquiring mode in a POOR COVERAGE area?
Is there a little box indicating that the GPS is ON
even though it is stuck in the Acquiring mode?
2. What shows up when the GPS indicates its battery is running low?
3. What happens when the GPS is turned OFF or the cable is disconnected.
3.1 While logging is ON
Does it go into dead reckoning?
Does it continue putting down a track?
Does the track look different?
Can you switch it back to tracking?
3.2 While logging is OFF
Does it go into dead reckoning?
Does it start to put down a track?
What does the track look like?
4. What happens when the GPS goes into a "POOR COVERAGE" mode?
4.1 While logging is ON
4.2 While logging is OFF
5. Can you see all the above changes or indicators regardless of the "Tracking Console" position on the screen?
6. Can you see the above changes if you chose to hide the status bar?
If these test are too complex or time consuming for you then please read the NTBS report
on the Royal Majesty accident with 1500 passengers aboard.
I ran into a problem with mine when the Electronic Chart System (Chart Plotting Software) went into dead reckoning and didn't come out of it till the computer was completely powered down an rebooted from cold. For more detail click here.
