This has happened to me only a couple of times in about 130 hours now...
Sometime after engine start, during taxi or run-up, my pitch trim has run to full up, despite not having touched the trim button on the stick *at all*. I noticed it after run-up (during which I keep the stick full aft), because it's a checklist item (pitch/roll trim set).
It's a Ray Allen trim servo, and Ray Allen stick grip with push-button trim buttons, wired just as diagramed by RAC.
It's disconcerting, has never happened at any other time though...and I have no idea if I can reproduce it.
Ideas?
My initial (ridiculous) thought was the the aerodynamic forces from run-up are moving the tab, but that can't be, can it???
ETA: Trim position is indicated via Dynon Skyview, wired as diagrammed/per Dynon installation manual.
Sometime after engine start, during taxi or run-up, my pitch trim has run to full up, despite not having touched the trim button on the stick *at all*. I noticed it after run-up (during which I keep the stick full aft), because it's a checklist item (pitch/roll trim set).
It's a Ray Allen trim servo, and Ray Allen stick grip with push-button trim buttons, wired just as diagramed by RAC.
It's disconcerting, has never happened at any other time though...and I have no idea if I can reproduce it.
Ideas?
My initial (ridiculous) thought was the the aerodynamic forces from run-up are moving the tab, but that can't be, can it???
ETA: Trim position is indicated via Dynon Skyview, wired as diagrammed/per Dynon installation manual.