Modern autopilot upgrades usually come with built-in altitude preselect and airspeed hold. Used properly, this automation is a useful tool in the bag of IFR utilities. It can reduce altitude busts and deviations, but with great power comes great responsibility. But it can be serious trouble—especially in the approach environment—if it’s misused.
Once sold as a complicated external option for retrofit autopilots, now-standard altitude preselect might be the best feature that’s been added to recent retrofit and OEM-standard digital autopilots and the IFR navigators and flight displays they are interfaced with. It allows you to dial in your desired altitude and then select the mode for climb or descent.
Whether it’s climbing or descending at 500 feet per minute or 2500 feet per minute, the system will calculate a smooth capture. Check here
for information on how to subscribe.