Hi all, I keep getting problems with autothrottle, & VSI problems.I create a flightplan, takeoff engage vor/loc and set a arbitrary airspeed of approx 250kts, set altitude hold as required by ATC, & climb rate of the default 1800fpm.What i am noticing, is that ATC ask me to go to the next altitude either higher or lower, i increase the value on the altitude hold, & the aircraft either climbs or descends, depending on what i put in altitude hold. What happens is the aircraft doesn't always climb at the set rate of 1800fpm, i get a lot of 500fpm, to correct this i click on the VSI up one to 1900 & then drop back to 1800, this works, & I stop getting nagged to 'expedite my transition'.The other problem is with my airspeed indicator which i set with autothrottle, this works fine, then all of a sudden the airspeed indicator reads 000kts,with lots of red dashed lines either on top or below the 000 reading, the majority of times the plane crashes.Unless i disengage autothrottle, even then the ASI reads 000kts, sometimes the speed indication comes back to normal, if i re-engage autothrottle, it may work OK for a while, but then it goes loopy again.What am i doing wrong, i'm sure it didn't do this before. It was happening on FSX SP1.I'm now running FSX+ acceleration, ASX,X-graphics,+landclass meshes.I'm not a great pilot, but know enough to know that's not working right.ThoughtsJohn

Your VSI problem seems to be an unadvertised feature (bug) in FSX and I notice it too. The IAS=000 problem can be solved. Turn on pitot heat (AKA probe heat); your pitot tube is icing up. This is not a bug. R-EDIT 'cause I can't type. R-

The need to change the VSI one notch then back existed fromday one with FSX. I noticed this early on and do it automaticallynow. I believe I've observed this behavior on other aircraft as well. Not just the default 737-800. Paul

Thanks for the replies, that explains it.Now that i'm using ASX, the weather is playing a new part that i had not noticed before, i.e the icing problem & reading 000kts.What do the red tick bars, above or below the ASI mean?Also glad to know that the VSI problem is, err 'normal' :)John

>Thanks for the replies, that explains it.>Now that i'm using ASX, the weather is playing a new part that>i had not noticed before, i.e the icing problem & reading>000kts.>What do the red tick bars, above or below the ASI mean?>>Also glad to know that the VSI problem is, err 'normal' :)>>>John"red" usually means there is a problem...these may be indicators thatthe ASI is not functioning normally....just a guess on my part. Paul

Alas, the 000kts icing is also a problem on default 747... I just can't find the pitot heat switch. :(-Kinetic