T&T: Autopilots on Auto..Auto..Auto

[Scott E. Bulger]

Mike observed:  "A side issue which I did not go into before is that if the
GPS is NOT driving the autopilot, I can very quickly tell if the person on
watch understands what they are doing, by simple examination of the track
they have created."

I'd like to provide some words of novice experience supporting Mikes
observations about autopilot steering.

I had the privilege of participating in 3 deliveries with Mike in command of
the vessel.  During these trips I got to experience first hand how a trip up
the coast can be accomplished by a series of known locations and headings
that only take a degree or two of adjustment for wind and current.  Prior to
this experience I thought a course generated by the computer and provided to
the AP via a NAV function was much more effective.

I had spent quite a bit of time on my Camano getting the Nobeltec software
to drive my Raymarine ST6000 AP.  I learned how to set the arrival circle
distance, adjust the rate of turn and configure it to return to a waypoint
after dodging off course.  This was all great experience and gave me good
knowledge of the interaction between the computer and the autopilot.
Imagine my surprise when we rounded one of the buoys outside the Columbia
River bar and Mike simply dialed the AP to a course and then didn't touch it
again for a hundred miles.  When I compared the reliability and value of
this approach against the time and energy I put into getting my computer to
steer a course I realized I might have invested my time more wisely.  It's
nice that I know a lot about getting the computer to steer the boat, but as
Mike pointed out, there are aspects of inputting a course and then
monitoring it's progress against an intended track that build critical
skills.

For one thing, if you let the computer steer the boat and become overly
dependant on it, you run the risk of having a lot of precious eggs in one
basket.  On one of the trips up the coast we had been under AP control for a
number of hours.  I was really proud that a portable computer I brought
along was keeping a faithful track of our progress up the coast.  As we
approached Umatilla Reef I Observed Mike use bearings on the land to orient
him to turn at exactly the right moment.  I glanced down at my Nobeltec
software, where a track I had laid out to avoid the reef was plotted.  I was
puzzled to see the course predictor line suggested we were heading straight
to the reef.   After a few moments I realized the software had locked up at
EXACTLY the wrong moment.  For some reason at the point the track took a
90-degree turn to the East, our progress on the display stopped.  There were
no indicators that the software was having any problems, other than the fact
the boat wasn't moving and the heading we were on was completely different.
Had we been in fog or if Mike had not known exactly when to alter course
because if his experience, I would have driven us up on the reef before
realizing the software had locked up.  Talk about failing at EXACTLY the
wrong time, this was it.  Since that event I've never fully trusted the
system.

There are more aspects of technology and risk in these observations than
Mikes original post and I don't want to turn this into a computers and
Nobeltec suck exchange.  These same problems can be experienced with
dedicated chart plotters and other software.

The point is as Mike stated, there are basic, critical, repeatable skills
that should be mastered before ingesting the opiate of a Glass Helm.  If you
come to rely completely on your high tech electronics to operate your boat,
you are setting yourself up for some potentially dangerous situations.  Be
smart, learn to master the basics first and then use technology to augment
your use of the boat where it makes sense and doesn't detract from your
continued acquisition of good basic skills.

Scott Bulger, Nordhavn 40II, Alanui, Seattle WA