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Look Mom! No
Hands!
One of the gadgets we added to Toy Boat 2 was a Simrad AP12R autopilot.
Luxury? Or irreplaceable tool?
Background
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Installation
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Commissioning
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Peformance
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Safety&Reliability
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Summary
Fishing offshore often involves a lot of driving around. Here are some of the
challenges that you face in a skiff:
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A skiff might not track as well as larger boats, making it difficult for
the captain to drive the boat while still helping to spot fish, watch the
sonar, set up lines, etc.
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Offshore fishing may require runs of 2 - 3 hours. It is difficult and
fatiguing to steer a straight course over such a long distance, especially in a
small boat which can easily be affected by chop and swell. You can also waste
fuel by not steering a straight course.
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If you fish alone, it can be almost impossible to aggressively fight a
large fish without an autopilot, because you can not drive the boat while still
applying maximum pressure on the fish.
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Landing a fish might be difficult because if you only have one or two
people aboard, it can be hard to maintain steerage if both people have to
handle the fish.
These don't sound like very strong arguments for an autopilot, do they?
Yet, after owning one for three years, we would have to
say unequivocally that an autopilot is one of the best things we
ever bought for the boat . We are less fatigued at the
end of the day, use less fuel, and can spend much more time focused on fishing.
Underlying Concepts
An autopilot "just" steers the boat on a constant course. That course
might be manually selected by the captain, or it might be supplied by a
GPS or Loran device. But like most things in life, the actual mechanics of
how this is done are a lot more complicated than you might think.
Because of wind, current and swell, at any given point in time the bow of your
vessel could be pointed in a completely different direction from
the course the boat is travelling, or needs to be travelling. If you
simply lock the steering wheel in one position, the boat might track straight,
but you will almost certainly be off-course in a matter on
minutes. How well the autopilot recognizes that situation,
and compensates for it, is the base criteria for evaluation how good
the autopilot is.
For a more detailed look at autopilots and how they work, take a look at the West Marine Advisor on
autopilots. Suffice to say, autopilots nowadays sport some pretty sophisticated
electronics, and are "semi-intelligent" devices, meaning that they learn
how to steer the boat based on prevailing sea conditions and boat position
("sea state").
Selecting the Unit
Autopilots have to be matched to:
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The steering system - For small powerboats, the steering
system is typically either a mechanical (cable) system with a rotary
cable drum or a rack-and-pinion, or a hydraulic system. Toy Boat 2 uses a
Teleflex NFB rotary cable steering system.
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The type of steering wheel shaft being used - Most boats
use a straight shaft, which holds the steering wheel at a fixed angle relative
to the dashboard. However, the Edgewater 175CC came with a tilt steering wheel,
similar to an automobile.
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The size of your vessel - Clearly a bigger vessel
required a more powerful drive unit. The capacity on most autopilots we looked
at were well in excess of TB2's weight.
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Whether or not you have multiple steering stations - Obviously,
not an issue for us.
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The capacity of the vessel's electrical system - Autopilots
can consume a fair amount of power, so in a small boat you need to make sure
your motor's alternator output and batteries can handle the extra load.

Simrad AP12R
Control Unit
For Toy Boat 2, we selected an arbitrary cutoff price of approximately
$1,000. After all, this is only a 17.5 foot skiff, right? At the
time, that left us with only two possible choices:
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The Simrad / Robertson AP12R - Simrad also offers
a sister unit called the AP14R, which differs only in the controller unit. The
AP14R controller has an LCD display which shows heading information as sensed
by the autopilot (useful in monitoring the system and debugging problems, as
we'll see later).

Raymarine Sport
PilotPlus
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The Raymarine SportPilot/SportPilot Plus - Based on a
review of their installation manuals, the only difference between the two
Sportpilot models is that the Plus model is designed for extended continuous
use, such as cruising or trolling.

ComNav 1420
If we had hydraulic steering, our choices would have expanded to include:
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ComNav 1420 - This unit sports an attractive price tag
and most of the basic features, but at the time we were looking, was an unknown
on the Internet bulletin boards we frequent.
Comparison
The AP12R is an under-dash unit, with the main
electronics and drive unit replacing the stock rotary drum. Before purchasing
this unit, you must make sure you have enough clearance behind the
dash for the drive unit, which is fairly large (about the size of
a loaf of bread). The AP12R has a controller which is designed to be
permanently mounted on the dash, and is used to initiate navigation, make
minor steering changes, and to calibrate the device. The AP14R controller has
an LCD display which shows heading information and some status messages. It has
a coiled cord with a mounting clip, and can be handheld.
The SportPilot Plus mounts on the end of the steering wheel
shaft, and goes under the steering wheel. In order to counteract the torque of
turning the wheel, the Sportpilot Plus also has a bracket which
connects the bottom edge of the autopilot to the dashboard. This prevents
the autopilot from spinning while turning the wheel. The bracket is
articulated so that the autopilot can be used with a tilt steering
wheel. It uses a lever on the unit (similar to a turn signal or cruise
control lever on a car) and some exterior buttons on the face to provide
control.
Base features on both units were very similar. Both units had
their proponents and detractors on the Internet.
Decision
In the end, we decided to go with the Simrad, because it
appeared that there were slightly fewer problems reported. But in reality,
it could have gone either way.
We also initially thought the Simrad would work out better
with our tilt wheel. But in fact, the SportPilot Plus
would probably have worked with the tilt wheel using out-of-the-box
parts, compared to the Simrad, which required a special shaft in
order to connect to the tilt steering wheel mechanism.
Pricing worked out about the same for both units, right
around our $1,000 target. We purchased the unit through
Dave's Marine Electronics, based on price.
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