"Paul" wrote in
:

Since the
"position report" message should get it's position directly from a GPS
unit, I can't understand how an error of this magnitude could occur.
I have not seen any similar errors with other ships.

If his GPS continues to report to the AIS transponder, even though it has
gotten confused from lack of signal or some idiot in engineering blinking
the power on and off causing it to reset, I can see that happening. Ever
notice how the GPS stores the last position it could get before it lost the
signal? That position, I'm sure, is what it's sending on NMEA out so the
GMDSS has the last valid data for the HF/VHF distress signal as she rolls
over.

I think his GPS was unlocking on loss of signal or had a power glitch from
the generator room.

--
There's amazing intelligence in the Universe.
You can tell because none of them ever called Earth.