IowaRV9Dreamer
Well Known Member
Hi - I'm installing a Trio Altitude Hold Autopilot in my plane, either an EZ-2 or EZ-3.... I'm looking for information about the use of pitch trim with the autopilot.
Trio's website has the follwing blurb (my emphasis added):
The altitude hold system microprocessor uses algorithms that detect when the system is demanding excessive servo pressure to maintain altitude ? which would be the case when the elevator control system is out of trim. This might happen on a long flight as fuel is burned off and the aircraft exhibits a tendency to climb. The A/H system will prevent if from climbing, but as fuel is burned the pressure that it must exert on the elevator control will grow. At some point, the system will ask the pilot to re-trim the aircraft by using the manual elevator trim system. Once trim is reestablished the message will be removed. (Note: If the aircraft has the Trio automatic elevator trim option, the trim motor will automatically keep the aircraft in trim as the flight progresses)
I have 2 questions:
#1 - For anyone with a Trio altitude hold and manual trim: How often does the system ask for a re-trim? Is it really "touchy"?
#2 - Is there anyone out there who has the automatic trim option and can share their experiences? For "only" a few hundred it seems pretty cool. I would like to know how it works in real life. It would be great to hear how you did your trim controls (still have a manual trim switch?, etc.) I see that you can adjust the trim using the Trio knob when the autopilot is off. Does that eliminate the need for a trim speed controller (because it makes smaller steps)?
Thanks for any info,
Trio's website has the follwing blurb (my emphasis added):
The altitude hold system microprocessor uses algorithms that detect when the system is demanding excessive servo pressure to maintain altitude ? which would be the case when the elevator control system is out of trim. This might happen on a long flight as fuel is burned off and the aircraft exhibits a tendency to climb. The A/H system will prevent if from climbing, but as fuel is burned the pressure that it must exert on the elevator control will grow. At some point, the system will ask the pilot to re-trim the aircraft by using the manual elevator trim system. Once trim is reestablished the message will be removed. (Note: If the aircraft has the Trio automatic elevator trim option, the trim motor will automatically keep the aircraft in trim as the flight progresses)
I have 2 questions:
#1 - For anyone with a Trio altitude hold and manual trim: How often does the system ask for a re-trim? Is it really "touchy"?
#2 - Is there anyone out there who has the automatic trim option and can share their experiences? For "only" a few hundred it seems pretty cool. I would like to know how it works in real life. It would be great to hear how you did your trim controls (still have a manual trim switch?, etc.) I see that you can adjust the trim using the Trio knob when the autopilot is off. Does that eliminate the need for a trim speed controller (because it makes smaller steps)?
Thanks for any info,