Van's Air Force
The definitive Van's Aircraft support community! Buying, building or flying an RV? Join our exclusive family of mentors and enthusiasts!
Navaid AP-1 Autopilot
- Thread starter scottm
- Start date
I had one in the plane when purchased. It had a broken switch that was soldered on the motherboard and touching it would cause jerking on the stick. Pulled and replaced with an EZ Pilot from Trio Avionics. I just added one wire to the GPS otherwise it was plug and play using the existing servo. Works fantastic and the guys at Trio Avionics were also fantastic. Trying to keep the Navaid AP1 alive wasn't worth the minimal cost to change out to the EZ Pilot.
What do you want to know or need help with?
The NavAid is old school. It will not follow a track, but it will take Left/Right analog error signals just like a VOR feeding a CDI. Your GPS will provide the same output - so in effect it will follow your fight plan. I flew with this for a few years before upgrading to the SkyView and its integrated autopilot.
But, there are so many better options instead of this coffee grinder. I would use it until it died then replace it with a dual axis autopilot.
Carl
But, there are so many better options instead of this coffee grinder. I would use it until it died then replace it with a dual axis autopilot.
Carl
My NavAid was set up as Carl describes with the Left/Right fed from the GPS. Didn't work very well but I'm sure was due to the damaged, soldered on switch. I looked at repairing it and quickly turned to replacing with new as the EZ Pilot was $1,295. It has a plug in connector and uses the NavAid servo without modifications. I added one wire from the GPS to the existing NavAid connector that took about 20 minutes. That was it and it works perfectly. It will follow the GPS provided course or you can set it to track your heading and adjust as you go. It really was the easiest and best $1,295 I've spent on an airplane so far and an incredible deal to get a functioning 2-Axis autopilot. I don't work for EZ Pilot - just a fan and grateful customer.
In theory, yes. As has been previously stated, the AP-1 accepts as its input analog voltages of +/-L and +/-R. So, if your GPS has that capability, and it is wired correctly, then the AP-1 will follow the commands from the GPS. You need to have the GPS on a course/track and manually turn the airplane to be on course, then engage the toggle switch to track mode. I always found it best to get on course and wait a minute or two before switching to track mode. I usually did this while in wing level mode (WL). Once on track mode, it would follow the GPS L/R commands very well with very little or no cross track error. If you do get a cross track error showing up on the GPS, meaning it is flying L or R of desired course, use the TRIM knob to get back on course. Trim towards the error. This is in the manual.
Later on, a company called Porcine developed a small module which would take the RS232 GPS signal from, say a handheld GPS, and convert it to analog voltages that could be used by the AP-1. Their website is still online (https://www.porcine.com/gps/sc/sc_frameset.html). You might have one of these doodads in your panel. Also, there eventually was a version of the AP-1 that had the Porcine smart coupler built-in. You might have one of those as well.
Either way, it would work the same. I built my RV6 30 years ago and am still flying it. In the original configuration, I had an Apollo GPS and the King KX-155 localizer feeding the AP-1 through a select switch. It worked very well.
