Engaging LNAV to flightplan in cruise

[mtabb 0]

Hello all. Am frustrated with the 747 as I've gotten so comfortable in the PMDG MD11F and now the 747 won't seem to cooperate as the MD11 does. When in Cruise, if I disengage from the flight plan and divert for a bit and then try to re-connect or engage the autopilot to LNAV on the Flight Plan, it simply will not engage. I've tried insuring that my flight plan waypoints are in order and that I am headed to the next waypoint in line and that I am within 1 mile from the course track and with the autopilot CMD light in green, the LNAV light will not lite and engage. VNAV will not engage nor will FLCH engage. Heading Hold will engage and HDG SEL will engage and steer the aircraft. Somebody please help so that I don't have to permanently put this aircraft in the hanger. Thanks, Mike

[phil747fan 14]

Mike, talk to your maintenance guys ... more seriously did you feed all the datas in your fmc ?is your autothrottle on ?is the fd on ? could you post a picture of your main panel here ? all the best. Phil

[engwerda 0]

Mike, Click on VNAV twice and that should reset it. If not, open up the FMC LEGS page and line select the next waypoint. Then paste it back in at the top of the LEGS page. It should then track direct to that WP. regards Gerry

[sheepfu 3]

what is your intercept angle? If I remember correctly, you have to be within 30 degrees to engage this mode. What I typically do is use HDG mode to steer to the correct heading, then I use the CDU to navigate direct to the specific waypoint. Once done, the LNAV should engage. Once engaged, the plane will spin 360s if needed in LNAV mode.

[yos233 1]

Since you are trying to get VNAV back does that mean you disengaged the whole autopilot? Make sure the disengage bar is up.