hi allim flying the 800 and i always let the FMC do all the speed and altitude calculations between dep and arrival airporthowever every single time after T/D the plane starts to descend fine, but then soon after i get an FMC msg saying that the VNAV has disconnected because of overspeed!how can i stop this from happening, i have let the FMC do all the speed and altitude calcuations so its not that i am putting in excess speed at the waypoints.thx

Clayton,You are letting the a/c descend on the VNAV PATH DESCENT wghich as been exstensively covered in this forum over the year.If you get a SPEED DISCONNECT message yuo are going too fast. The VNAV PATH descent will care about the path but lets the crew monitor speed. Above FL100/10000 VNAV allows speeds up to a couple of knots below Vmo or the barberpole. Below FL100/10000 VNAV will give a DRAG REQUIRED message at 10 knots above calculated target speed and will disconnect at 15 knots above target speed.Remember. You are responsible for speed in a VNAV PATH descent!For more information. Please do a search on the forum.Oh. And always check the numbers crunched by the FMC. Never rely on a computer! ;-)Hope it helps,

Lower flaps, or more drag (spoilers), Like Matt said their are extensive posts about this and am sure you will not have trouble finding the answer to your question ;)

ok i will do a check on that later, got some other problems to figure out like why i cant see any other aircraft in VATSIM through Squawkbox!!!