No Rudder Trim

[Hvwaitz]

Depending on load and powersetting I need to hold the rudder for straight flight. The PA28 has a rudder trim, there is none in the DA40, is it? On long trips it can strain the one leg quite a bit. It also gives a strange feeling. I adjusted the rudder flap to minimize it, but there is always some pressure needed. Do you know this effect? Is there anything you can do?

[CFIDave]

Go do a search on DA40 "corked" nose wheel. Many DA40s are notorious for nose landing gear (with fairings) that rotate either right or left at takeoff and get stuck there -- causing yaw in cruise that requires constant rudder pedal pressure to "center the ball." You'll also lose 3-5 knots of cruise airspeed when this happens due to the additional drag.

Various fixes that have been tried include proper adjustment of the nose gear pivot torque/tension, avoidance of takeoffs during crosswind conditions, removal of the nose gear fairing, addition of a fin to the fairing, etc.

[Rich]

If you look at the "corked nose wheel" threads you'll see more than you wanted to know about this. But to more directly answer your question, the rudder trim tab should be adjusted to eliminate rudder pressure for a typical cruise situation. That's the best you can do. Rudder trim is rare in single-engine aircraft models. I do recall having rudder trim in my PA28-140, which was kind of amusing, given its low power.

I have long thought rudder trim would be somewhat handy in the DA40. The most likely approach would be an adjustable spring/bungee device of some sort. Since putting on the fin Bret came up with and making a tweak to the trim tab this is no longer a problem in my plane.

[Hvwaitz]

If you look at the "corked nose wheel" threads you'll see more than you wanted to know about this. But to more directly answer your question, the rudder trim tab should be adjusted to eliminate rudder pressure for a typical cruise situation. That's the best you can do. Rudder trim is rare in single-engine aircraft models. I do recall having rudder trim in my PA28-140, which was kind of amusing, given its low power.

I have long thought rudder trim would be somewhat handy in the DA40. The most likely approach would be an adjustable spring/bungee device of some sort. Since putting on the fin Bret came up with and making a tweak to the trim tab this is no longer a problem in my plane.

Thanks for your comments! What is "fin Bret" and "making a tweak to the trim tab" mean?

[Hvwaitz]

Ok, got it. Thank you everybody!!

[Rich]

Thanks for your comments! What is "fin Bret" and "making a tweak to the trim tab" mean?

The "fin" was something worked up by one of our former members (Bret) here that bolted on nicely to the nosewheel fairing and eliminated the "corked nosewheel" problem. Mostly this had the effect on my plane of giving me consistent cruise performance. I also straightened the rudder trim tab when I did this, making a guess as to how much. These two changes resulted in feet-on-the-floor in the normal cruise range.

In high-speed descents and during takeoff and full-throttle climbs, of course, left rudder and right rudder pedal pressure, respectively, are still required as one would expect.

[smoss]

Lucky you Rich to get a Bret-fin. I am sad no one here wanted to run with a 3D printed version.

[Rich]

Lucky you Rich to get a Bret-fin. I am sad no one here wanted to run with a 3D printed version.

Me too. Hm, I just realized how easy it would be to steal mine. I need to guard my location carefully when parking away from home

[yl472401]

My DA40 seems to have the same kind problem- constant left yawn tendency. my CFI recommended dead leg technique and I'm thinking about something better to solve the problem... Maybe just take off the wheel fairing and be done with it.

[jwx96]

I think it is much better without the wheel fairing. I didn’t put mine back on this spring.