Few minutes ago i fly short trip,before reach T/D point is normal,but when close to T/D then i notice T/D point was irregularity move on plan route,like advance、retreat、advance、retreat......And during approach with VNAV path,VNAV path point get same irregularity move, up down up down.....Has any one notice?

Just flew KMDW - KMCI in the 700, saw no problem at all with VNAV. Descent ondown to a full autoland was flawless. I'm SO happy :)

Few minutes ago i fly short trip,before reach T/D point is normal,but when close to T/D then i notice T/D point was irregularity move on plan route,like advance、retreat、advance、retreat......And during approach with VNAV path,VNAV path point get same irregularity move, up down up down.....Has any one notice?

T/D is based on a mathematical calculation involving variables, so sometimes it will occasionally shift if these variables change during cruise.

I believe Ryan said this was one of the minor irregularities that they couldn't quite fix 100%, the TD point is fluid and is effected by a myriad of variables, the dodgy FSX weather engine being one large contributing factor.

But before install SP1,those T/D point and VNAV path point is very normal.

I had this happen before SP1.jos denis

So did I hence the reason I know the answer, bit obvious really isn't it.

I fly more time,seem never happen again,so i guess it's some kind of fix...