Do you have an example of a roll autopilot which doesn't make turns? I don't know of one.Depends on the autopilot. Some don't make turns at all.
That would probably be because the GPS isn't commanding enough of a turn to reach standard rate before it is commanding a rollout. It also might be due to crosswind causing a less-than-standard-rate turn to be necessary to join the desired ground track from where the turn was commenced. Otherwise, it should be commanding standard rate.The autopilot I've used (STEC-50, with retrofitted coupling through an Aspen and Garmin 430) makes turns noticeably slower than standard rate when coupled to GNSS.
The most basic autopilot I know is the Century I, and it doesn't have heading hold at all, but it does have a standard rate turn command.The most basic autopilot just holds your current heading.
Do you have an example of a roll autopilot which doesn't make turns? I don't know of one.
Well, the only "wing leveler" type of autopilot I've seen in 43 years of flying is the Century I, and it has turn command.He may have been referring to Wing Levelers? Which 1/2 century ago, used to be considered as autopilots (of sorts), FWIW
Well, the only "wing leveler" type of autopilot I've seen in 43 years of flying is the Century I, and it has turn command.
Ah, yes -- the "PC" system, right? Positive Control or something like that? I remember now having to fight it while flying a Mooney. Wouldn't call it an autopilot, of course, but yes, it did do its best to keep the wings level despite any pilot desires to the contrary.I thought the Mooney-installed device on my 20F was a wing-leveler only.
Ah, yes -- the "PC" system, right? Positive Control or something like that? I remember now having to fight it while flying a Mooney. Wouldn't call it an autopilot, of course, but yes, it did do its best to keep the wings level despite any pilot desires to the contrary.
Right -- there was a button on top of the yoke you had to hold down to disable it whenever you wanted anything but wings level flight.Yep, and my opinion of the value corresponds with yours. But my thumb strength improved markedly while I owned it.
Are auto pilots typically set up to make the turns at standard rate?
Ah, yes -- the "PC" system, right? Positive Control or something like that? I remember now having to fight it while flying a Mooney. Wouldn't call it an autopilot, of course, but yes, it did do its best to keep the wings level despite any pilot desires to the contrary.
We put a heavy rubber band on the yoke to hold the cutoff button down for traffic pattern operations and air work.
Are auto pilots typically set up to make the turns at standard rate?
S-Tec autopilots and a few other units (e.g. all Brittain autopilots and the Century I) sense turn rate (actually turn+roll rate but for your question that doesn't really matter) directly with an input from a specially built turn-coordinator. With those autopilots the turn rate will be consistent on any big turn and typically is limited to "standard rate" or 3°/sec with no limits on bank angle. That means the bank angle will be nearly proportional to the airspeed. That's not much of a problem for "slow" airplanes with cruise speeds below 200 KTAS because the max bank angle won't exceed 30°. But at 400 KTAS the bank angle would exceed 45°.Are auto pilots typically set up to make the turns at standard rate?
Mine makes S-turns well beyond standard rate, pretty much continuously except in wing leveling mode where it chases the turn coordinator back and forth in a very relaxing rocking motion. Haha.