I just took delivery on the FSD Seneca which has a Prop sychronizer that works, I think. :) What is the correct flight mode to use prop sync? Take off? Climb etc. What are the precautions? Thanks in advance.BobP :)

If I'm not mistaken, prop-sync should only be turned on during normal or cruise flight to help eliminate the noise un-sync'd twin props can make. But it isn't used during critical phases such as take off or landing because if you had an engine failure the system would try to sync the good engine's prop to the failed engine which could be a problem :)Just my understanding :)

That's how I've always used it as well.Rick

You wouldn't use it on takeoff or landing, in case an engine fails, you don't want the other prop to follow. If you have something attempting to synchronize the engines by rpm or power reduction/increase, than a reduction in one will cause the other to follow suit to one degree or another. Depends on manufacturer. But, you have enough trouble on your hands with yaw if an engine fails on takeoff without the prop sync being engaged.P4 2.81024 DDRAM800 Bus36 gig SATA hardrive80 gig harddriveATI Radeon 9700 ProCH yoke/pedalsElite Multi quadrant19" inch monitor-Soundblaster PCI 512Win XPInstrument rated ASEL -270 hoursAOPALawyerPilots Bar Association"Men without dreams are never free, twas thus this way and thus will ever be."

I was using it during cruise only and your information confirms my choice. Thank you!BobP :)