Originally Posted by
rleffler
You can only have one active flight plan.
I experienced something similar back in September on a long cross country on an IFR flight plan. Just shortly after take off, I experienced a hardware issue that resulted in my primary GPS unable to communicate with the EFIS. I quickly transferred my flight plan from my GTN650 to the INTFP plan manually, changed the GPS source to the AFS GPS, and continued the flight. I was still legal because the GTN650 was still operational, it just couldn't talk to the EFIS. All I had to do was to manually ensure that the two flight plans generated the same route and position. If you are VFR, it's a no brainer.