[CA] Procedure to align Evolution ACU-150 p70r Auto-Pilot to GPS

[Chuck - Raymarine - Moderator]

Karlista,

Q1. I performed all of the steps above when the auto-pilot was commissioned in Chesapeake, VA. The COG and Heading vector lines were aligned within one degree. When I moved the boat to Morehead City, NC, something changed and the COG and Heading vector lines of off by about 10 degrees.
A4. Leeway can cause the heading and COG vectors to differ from on another. Should the problem persist when steering directly into the current, then it would be recommended that the Align Compass GPS feature be used again. Afterwards, you should still expect COG and Heading vectors to deviate from one another when the vessel is being subjected to leeway (wind and/or current). Leeway effects will also increase as the leeway magnitude to vessel speed ratio increases.