One thing I always wondered about this how APs treat this pitch hold / roll hold mode. When I engage the DFC90, it always has both a pitch and a roll mode. It can never only have one which is different from the S-TECs.
If I don't specifically chose a lateral or vertical mode, then it will use hold mode. Let's say I press ALT, then it will switch to maintain altitude + maintain roll. If I disable it and then press HDG, it will switch to maintain heading + maintain pitch.
So far so good. What I am wondering is why the autopilot does not offer an option to go back from a selected mode to the hold mode. In order to switch from maintain altitude to hold pitch, I have to disable the autopilot and select a lateral mode.
Is there a certification reason for this?
Good question ... I asked myself the same thing, But I really like this feature... it's much safer (in my view) than to select other modes shortly after take-off. I first use AP only... and the go to IAS+ALT or VS+ALT at a safe altitude
