High Trim position

jwjenks@netzero.net

I have a 1977 210M just back from the avionics shop: New Avidyne IFD550, Aspen E5, and an STec 3100 W/yaw damper. When on cruise at 165kts IAS, 440lbs in the front seat, the trim wheel indicator is near the top of the window. As you look down, the indicator is just below the T in the word TAKE – OFF. Parallax puts it below that, but that’s what I use for reference. At that position the trailing edge of the Trim tab is at least 1.5″ up from the TE of the elevator, forcing the elevator down. At this cruise speed the front of the outboard counterweight on the elevator shows about 1/2″ above the horizontal stab. As I add passengers and bags in the back seats I will have to add more DOWN trim putting the indicator near the stop, which moves the trim tab to it’s near max position of 25 degrees up. I worry this is unusual.

The plane seem to fly faster than before. Maybe I shouldn’t complain. It did get a Continental engine overhaul and new Hartzell prop (HC-J3YF-1RF/F8068-2) this summer just before the avionics upgrade. Is that what makes it faster? and creating more downwash on the elevator?

Is the high trim tab position on the elevator normal?

Scott Sherer

Hi and thanks for writing. This is an airworthiness issue and not to be taken lightly. So here are my recommendations. 1. Have you recomputed your weight and balance envelope after the avionics upgrade? Have you removed your vacuum system? This could lighten your nose up 30 pounds, give or take. After you have a new W&B envelope, have you rerun your W&B ? Are you in the envelope? 440 pounds in the front seats is alot of weight. 2. Pull out your service manual and look into the rigging section. I would consider rerigging the airplane and see if it's done right. 3. Get with your avionics shop and discuss the issue and get their recommends. Good luck!