I used FMC to program my route. And sometimes do impromptu landing by manul tuning NAV1 to airports I feel like coming down. The problem is FMC keeps switching NAV1 back to auto. How can I stop it?ThanksMichael TanYSCB

I stand to be corrected on this, but, I believe you need to enter the freq/crs into the FMS NAV/RAD page for NAV1. To go back to automatic enter a letter A.I always thought that just hitting the AUTO/MAN button on the main panel would do the trick, but I have seen mine go back into auto mode by itslef too. Setting the freq in the FMS seem to do the trick though.I'm not sure of the exact page in the manual but it is covered in there. :-)

I checked the manual. But it deals more with putting things in auto than in manual. Will try your method...CheersMichael TanYSCB

FYI, switching between flightpath mode and one of the rose modes will cause it to go back to AUTO when going back to the flightpath mode.