Jim Donohue wrote:



Sure they were. by the time they were 200 miles out they had a multiple
mile error.

The chief officier and navigator both stated that a cross check of the LORAN
was done. The second officier stated the LORAN was used only as a backup to
the GPS.

The NTSB found that the LORAN was never checked and should have been.

The 2M IS the navigator. At any rate, in the past, occasional multi mile
variances between GPS and Loran, though not common, did occur ....
frequently when working the limits of Loran ranges. So, a variance was
not necessarily a "drop dead". What it was, was cause to check systems
and do concurrent plots to see if it corrected .... they did not.



They had failure indicators staring them in the face the whole time. They
just never looked. Makes little difference what the failure is if the
indicator is not noted.

Complacency ..... it'll bite you in the ass at the worst possible moment.



If you are going to be navigating, you want back-ups to your back-ups.
Sure, You can carry 20 hand helds and 4 cases of batteries, but what
happens when the Chit, negatively hits the fan and all you know is GPS?


No they were simply not very competent. They were plotting the positions
hourly...but taking the positon from the busted system. Plotting the
positon from one of your 20 handhelds would have blown the whistle before
they were an hour into the failure.

I can't remember if they were transferring plots from the plotter to
paper charts. No matter, doesn't matter if it was a hand held or Loran,
a plot from either would/should start mental alarms ringing.


What happens when the system fails and you are not aware of it and you go
merrily on your way, believing it's working?
No, they were GPS Centric. They believed everything was fine, when a
system check would have said otherwise. They didn't use back-ups/double
checks, they believed the GPS would always work so consequently the
integrated nav system must be correct and never needed checking on, for
whatever reason.

Basically what I'm saying is go back to the first basic error. The GPS
wasn't working, no one checked to see if it was... they were "centric" in
that they assumed it would be, when in truth, for any number of reasons it
may not be and the prudent navigator realizes this and checks, especially
in areas such as the Nantucket-Boston Safety Fairway.

otn


And a major finding was that the system design was deficient in a number of
human factor ways that provided the environment for the grounding. For
instance the GPS had a suitable external alarm...which was not hooked up.
The report strongly suggest that redundant receivers should also have been
part of the system. The system should have cross checked the LORAN and the
GPS. All kind of simple stuff.

Yes to all, however, the officers should also have been doing this since
otn's law applies (anything designed by man, built by man, operated by
man, and maintained by man, is subject to catastrophic failure, for any
of the above reasons.) and THEY were part of the alarm system, since
alarm systems are known to fail.


otn