I need help... Don't understand why whenever I fly all attitude, with my auto-pilot on with SPD, HDG and ALT on, it goes to FL CH in the end and all screw up.. What's FL CH and how to encounter this problem ? Thanks !

I'm not sure I actually understand most of the question, but as far as the FL CH switch, Selecting FL CH results in a computed optimum climb/descent rate that varies with available a/c performance- speed protection is offered, hence VS will vary. Also, FL CH automatically opens the IAS window, selecting higher ALT engages in THR mode and CRZ (if active) changes to CLB unless an engine is inop in which case it changes to CON. Selecting lower ALT results in IDLE and HOLD. Once capture occurs, pitch changes to ALT and A/T engages SPD.If you are flying SPD, HDG and ALT you are in direct control of the A/c through the MCP. Simply selecting another ALT and actioning the FL CH switch will result in a speed protected climb or descent.......what's the issue.....??Might I suggest some time in PMDG OPS? There are a whole series of articles and lessons that would help.http://ops.precisionmanuals.com/wiki/Main_PageBest-Carl F. Avari-Cooper BAW0225http://online.vatsimindicators.net/980091/523.png

Thanks for replying... Mmm... Sorry I don't quite understand.. How to not let FL CH be activated ?

Hi,First off, please read the forum rules - you're required to sign your real name to your posts.Second, please read the manual for the aircraft and go through the Type Rating Course tutorials available here:http://www.precisionmanuals.com/priv/pages/down/docs.htmlYou just need to gain some knowledge on how the aircraft works. This isn't something you can fly without doing some studying, it's a simulation of the real thing, especially the autopilot.