Need your help fellows - fighting elevator on final

[skunkwurk]

I've got to ask, but how low is your idle? I have had planes that needed to have a very low idle before they would settle nicely onto the runway. I generally try to get a reliable idle that is low enough that the plane will barely taxi without increasing power.

Judge,

That's actually a great question. I currently have the idle set high, specifically since the motor is new and I'm putting the initial tanks through it, I'm still feeling it out. Plus my field is all grass, so a low idle isn't really that necessary, as it would be on a paved runway. It could be that, I would have to put a tac on it, but I'm sure it's on the high side. You might be on to something !

 

[Judge]

You might try getting set up on final and once you are sure you have the runway made to simply hit the kill switch (you use one, right?). I'll bet it settles nicely onto the runway.

 

[skunkwurk]

I've got to ask, but how low is your idle? I have had planes that needed to have a very low idle before they would settle nicely onto the runway. I generally try to get a reliable idle that is low enough that the plane will barely taxi without increasing power.

I'm worried about killing the motor on final, I've had to go around on a few of the flights. The plane does slow down but does not seem to descend unless I push on the elevator.

 

[Terryscustom]

If the tail falls first even at high idle that further indicates tail heavy.

Tell you what, if you want me to run some calculations to give you the actual calculated neutral CG I'd be happy to do it. If you PM me the dimensions off this drawing I can calculate the LE sweep and all that stuff that are hard for you to measure and give you a very accurate CG. Just PM me A=xx", B=xx" and get as close as you can, at least to the 1/16".

I'm kinda strange like that, I have gotten away from even looking at the CG in the manual for an ARF until I measure and calculate to where I want to start. ARF's will give you a range but it's funny sometimes to see where that range actually lies in relation to neutral starting point. I've helped some friends with off brand ARF's that were not even remotely close to actual CG.

 

[Judge]

I'm worried about killing the motor on final, I've had to go around on a few of the flights. The plane does slow down but does not seems to descend unless I push on the elevator.

I'm talking about killing the engine once you are committed to landing, not up at a point where going around is something you might need to do

 

[Kevin-Young]

When they give you the cg point in the manual are you supposed to measure it with the aircraft upright or inverted?

 

[Naughty Monkey]

Put an idle down on a switch for landing only. If you end up having to go around, be gentle on the throttle if you are worried about it quitting.

I'm worried about killing the motor on final, I've had to go around on a few of the flights. The plane does slow down but does not seems to descend unless I push on the elevator.

Thinking out loud a little here about this. So if you are at idle and have the plane in a slightly nose high attitude, it climbs? That would mean the idle is too high. Just wondering if this is what you mean by having to push the elevator to descend. An idle down switch might verify this too.

 

[Bunky.F.Knuckle]

Here you go Terry. I was only able to take shots of the left stab-half, as I can only leave installed the one side in the trailer. Let me know what you see.

Regards,

sc

View attachment 30441 View attachment 30442 View attachment 30443 View attachment 30444

I like the looks there. If the clevis on the elevator control horn only has a sleeve, no ball, then you may need the "freedom" for the knuckle to rotate to maintain a straight pushrod.

A friend of mine loctited the clevis onto the studs, to prevent movement, and ended up ripping the clevis off the stud, because it couldn't move.

My 35% Carden is outfitted much of the same way, as is my 42% Dalton 300. Nothing wrong there.

Sounds like you may have a stab incidence issue, with the LE of the stab angled down, giving you an uncommanded "UP" command. Which way did you have to trim the elevator on your maiden?

 

[skunkwurk]

If the tail falls first even at high idle that further indicates tail heavy.

Tell you what, if you want me to run some calculations to give you the actual calculated neutral CG I'd be happy to do it. If you PM me the dimensions off this drawing I can calculate the LE sweep and all that stuff that are hard for you to measure and give you a very accurate CG. Just PM me A=xx", B=xx" and get as close as you can, at least to the 1/16".

I'm kinda strange like that, I have gotten away from even looking at the CG in the manual for an ARF until I measure and calculate to where I want to start. ARF's will give you a range but it's funny sometimes to see where that range actually lies in relation to neutral starting point. I've helped some friends with off brand ARF's that were not even remotely close to actual CG.

View attachment 30534

Thanks, Terry. I'll take the measurements today and send them to you via a PM. I was thinking of using the three scale under the wheels method to verify the CG, I'll wait on that until I hear back from you. Look out for the PM.

 

[Terryscustom]

I like the looks there. If the clevis on the elevator control horn only has a sleeve, no ball, then you may need the "freedom" for the knuckle to rotate to maintain a straight pushrod.

A friend of mine loctited the clevis onto the studs, to prevent movement, and ended up ripping the clevis off the stud, because it couldn't move.

My 35% Carden is outfitted much of the same way, as is my 42% Dalton 300. Nothing wrong there.

Sounds like you may have a stab incidence issue, with the LE of the stab angled down, giving you an uncommanded "UP" command. Which way did you have to trim the elevator on your maiden?

Good point, I "assumed" there was a ball on there. And I completely forgot about a possible incidence issue