The Simrad AP12H autopilot package comes with a course computer, control head, compass, hydraulic pump, and linear feedback unit.
Another version of this autopilot is available for boats with mechanical cable steering.
Operation of the Simrad AP12H is fairly simple. With the unit turned on, the Stby/Auto LED will blink, indicating the autopilot is ready to go to work.
Pressing the Stby/Auto button engages the autopilot in a course-hold mode and turns the LED on steady. Whatever course youre steering when you select the Stby/Auto button is the course the autopilot will hold.
To change course one-degree, push the port or starboard arrow button once; youll get a single beep and a single flash on the associated LED to confirm the command. Hold either button down and youll get a 10 or more degree course change. The longer you hold the button, the more the course changes. Each 10 degrees of course change is confirmed by a double beep and double LED flash.
Tracking a Course
The Simrad AP12H is also capable of navigating to a waypoint when GPS data is available. To engage the navigation mode, first select Stby/Auto then Nav. Both associated LEDs will turn on steady to indicate lock on.
Gain can be adjusted in any mode: One push of the Gain button will flash the Gain LED from one to nine times, corresponding to the amount of gain currently selected. To increase gain, press the starboard arrow; to decrease, press the port arrow.
We found the default gain setting of five to work well for us over a wide range of operating conditions. In seas less than 3 feet, the autopilot tracks a straight course nicely, both in the navigation mode and the course-hold mode. Occasionally gain adjustments are needed as conditions change.
The arrow buttons are active in all modes and serve as a dodge feature. This lets you maneuver around an obstacle close ahead without disconnecting the autopilot. One caution, we tested the dodge function at various gain settings and found the turns to be quite aggressive at high-gain settings. At our preferred gain setting of five, a dodge turn is smooth and effective.
About 18 months into our evaluation, the autopilot failed to engage when selected. After conferring with Simrad support, we were able to diagnose the problem as a failed linear feedback unit. Its a long cylindrical part that attaches to the hydraulic steering cylinder on the engine. Our guess is that the constant exposure to salt water led to an early demise. We dont think this should have happened in such a short time and in our opinion, this part needs to be reengineered for a longer service life.
Our warranty claim for the new feedback unit did not go well. Once we confirmed the problem, Simrad asked us for the autopilot serial number to determine if it was still under warranty. The company said it was not and advised us a replacement part would cost almost $400. This seemed expensive for a single piece of a $1,400 autopilot system. So once we got over the shock of the repair cost, we began to research the situation and discovered that our unit should still be within the 2-year warranty based on our purchase date.
Simrad calculates the warranty date by adding three months to the time the unit is shipped to a retailer. In our case, the retailer actually had the unit in stock far longer. We dug out our receipt and made a copy. Simrad required it before it would honor the warranty claim. With proof in hand, Simrad agreed to ship us the part but not without making us jump through one more hoop. We had to pony up the money for the part and then wait for Simrad to credit us.
Another big issue with the Simrad AP12H is a noisy hydraulic pump. We installed the Simrad autopilots pump about 18 inches below our helm station and through-bolted it to the center consoles aft bulkhead. That puts it about shin high to the driver and totally contained inside the center consolea location that made accessing and connecting to the existing steering lines easy.
At slow speeds, the pump is loud enough to interfere with conversation and always draws comments from passengers. Even at cruising speed, the pump can be heard.
Simrads Phil Roberts explained why the pump is so loud. “The pump noise is related to how it pumps. This one is a piston type. We do not manufacture it. Our other autopilots use meshing gears which tend to be quieter” says Mr. Roberts.
The Simrad AP12H Autopilot performed well over the course of two years, but the noisy pump is a definite drawback. We were also disappointed in the early failure of the feedback unit and complex warranty procedure.
When we bought the Simrad AP12H, it was the least expensive autopilot we could find. Today it remains an inexpensive small boat autopilot priced around $1,400 at a variety of online marine electronics retailers.