Ray Allen servo

[bluesflyer]

I received a response back from Dan W. which said 25 degrees up and down should be good. I measured 25 degrees up and got somewhere close to 7/8" from the top of the elevator skin to the top of the trim tab skin.

[bluesflyer]

Thanks Fred and Dan!

Dan, I’ll be interested to hear how the trim works on your test flights. Neat mod that you made for your servo. I’m using the factory cable and attach setup, but with the servo moving the cable.

The optional SB for tweaking horizontal incidence leads me to believe that I’d need to see greater than 3/4” trim tab sticking up in cruise flight. The HT incidence SB would change this dramatically, but this is the only reference to how much trim tab travel is needed. I’m thinking at 200mph, the needed trim would be greater than 1” up trim tab.

I’m thinking that I can attach the cable higher up on the trim tab attach bracket to change the arm length and total travel.

It would be very helpful if someone with the manual trim setup could measure the up and down limits relative to the elevator. Pictures like Dan posted would also be a great help.


This is an excerpt from the HT SB:

Some information follows to help you decide if you want to adjust the HT incidence.
The prototype N515XP and 3 other Panthers have the incidence set -0.8°. Two are LS Corvair powered, one is an LS 0-320 Lycoming powered, and one is a Sport with 0-320 power. All can be trimmed hands off in pitch at any speed operating speed.

This will yield hands off level flight at 140 MPH indicated and about 50% of the total forward trim at the lever (nose down). The trim tab will be displaced about 3⁄4 inch upward at the trailing edge of the tab. The aircraft can easily be trimmed for speeds to 200 MPH IAS. The elevator itself will be displaced downward approx. 3/8-1/2 inch wing
length, and engine (cruise speed) will have some effect on required forward trim.
Two other Panthers have horizontal stabs @ 0.25 and 0.5. Both have long wings and Lycoming 0-320 engines. Both require less forward trim than the others.

[PlaneDan]

I have a T2-7A that I was using in my KR-2 and it worked well in that plane.

Here are two photos showing the deflection on the Panther that I am almost ready to fly.

2019_09_21 _TrimTabDeflection_01_.jpg

2019_09_21 _TrimTabDeflection_02_.jpg

Sorry for the delay in responding, but I thought a pic would be better than words.

[fwellman@att.net]

I am still in the process of building, so in reality I dont know how much travel is actually necessary. However, having said that, with my manual trim lever I get about 2 1/2 inches of travel on the cable. Looking at the movement of the tab itself, that seems pretty excessive, but I cant really say how it will perform in flight. Not much help I'm afraid. Hopefully someone with a flying Panther will respond.

[bluesflyer]

Hey everyone, I'm new to the forum and a new Panther LS builder. I bought a kit that was partially completed and I'm in the process of figuring out a few things that I have questions about.

The kit came with a Ray Allen servo for the elevator trim. The model is a T3-12A and it has 1.2" of travel. Is this enough travel to move the trim tab through it's required range?

Thanks, Keith