How to command autopilot to start a fixed rate descent? Is it possible to command an autopilot to start a fixed rate descent? For example to avoid weather during the cruise phase? From what I have read the autopilot would maintain constant speed and altitude until interrupted but havent found a fixed rate descent function.
Here is what typical autopilot controls look like


Image source: What is a &quot;Flight Director&quot;?

The pilot can set the required altitude, as well as the required vertical speed to get to that altitude. A cruise decent will typically use a shallower descent than an approach descent.