matt.hocker
I love flying!
- Joined
- Jan 16, 2013
- Messages
- 15
I have a SeaMax M22 which is a pusher engined amphibious aircraft with a Rotax 912ULS motor. The previous owner installed an EFIS-D100, EMS-D120 and AP74 with two servos, one for pitch and one for roll. The servos are securely mounted to the aircraft hull and to the rods which move the elevator and aileron control surfaces.
However the nature of the pusher engine is such that the aircraft has much less aileron authority than rudder authority, due to the engine's prop wash being directed over the tail surface directly. Correspondingly, the elevators are very effective.
In diagnosing some other issues with the system, I have done a DSAB reconfiguration and reconfigured the AP74's servos. It passes the tests correctly.
(Note to others with AP issues: I needed to check all the servo connectors - one had a female blade that had been pulled out. My mechanic says that these type of connectors are very poor.)
In testing the AP74, I find it to be very inaccurate. When I try to get it to hold a heading and altitude, it hunts for both and then when it gets close, it never levels out properly. It also tends to make very jerky control movements.
I had a passenger with me and they commented that I fly better than the AP does - nice to hear of course but I would at least like it to be smooth.
What further configuration can I do to make this autopilot more useful?
Thanks.
However the nature of the pusher engine is such that the aircraft has much less aileron authority than rudder authority, due to the engine's prop wash being directed over the tail surface directly. Correspondingly, the elevators are very effective.
In diagnosing some other issues with the system, I have done a DSAB reconfiguration and reconfigured the AP74's servos. It passes the tests correctly.
(Note to others with AP issues: I needed to check all the servo connectors - one had a female blade that had been pulled out. My mechanic says that these type of connectors are very poor.)
In testing the AP74, I find it to be very inaccurate. When I try to get it to hold a heading and altitude, it hunts for both and then when it gets close, it never levels out properly. It also tends to make very jerky control movements.
I had a passenger with me and they commented that I fly better than the AP does - nice to hear of course but I would at least like it to be smooth.
What further configuration can I do to make this autopilot more useful?
Thanks.
