I have a H9 Alpha trainer (12 flights w/ help, now I solo). I was wondering how do you increase the movement of the control surface's. I want the rudder and elevator to have a higher degree of angle when they are at full turn. I currently have the control rod set on the outer most hole on the servo link and control surface link. Is their anything else I can do?? Thanks.

new2this, hi ya . dont take this as gospel. if i remember right if you move the clevis inward towards the control surface it will increase the throw. i may be wrong so just try it in your shop and see.. ps. the alpha is a good plane. mine is still in one peace...... have fun spooner

yes the way to increase throws is to move clevis in toward the control surface and or out on the servo arm

wow i knew something..........lol

Alright. Thanks for the help!

your welcome

new2this,

Before you start going ballistic with the control throws, consider this... The designers give recommended throws for a reason. A trainer such as yours is only going to perform to a certain degree. If you go wild with the throws (esp the elevator), landing can really become a handful. Remember, the more throw you have, the more sensitive the controls will be (make sense?). A trainer with a very high lift wing will balloon easily during your approach and flair if you feed in just a tad too much elevator. More is not better in some cases.

For what it's worth...

Yeah last night I was adjusting them and that thought did cross my mind. This plane flies so simply that I am not worried so much about losing control (The plane nearly lands itself). I am more worried the rudder or elevator ripping off the plane in mid flight. I am going out tommorow and I will see what happens.

"sniff" Wish I could go out tomorrow. -30C and 2 feet of snow

Hello, I was just thinking ....if you used the outermost holes on the servo arm and the control horn, you aren't getting maximum throw-not that I am suggesting you should necessarily. Its like a 10 speed bike ....outer hole at servo, inner hole at horn for max travel. Keep in mind this is not always wise vis-a-vis servo power and authority.....there might be other ways to quicken the control movement of your plane....removing a wing bay or more rearward Cg might be the ticket-what do you and others think of those ideas? YMMV
PS...I just reread the other posts and see the control horn hole issue had been already touched upon! oh well. Good luck

I have read in the other post/reviews that these can be nose heavy out of the box. I have thought a little about moving the reciever back towards the tail in order to move the cg. And I don't know what a wing bay is so I am not sure if I can remove it D. I do appreciate the suggestions. I think maybe tonight I will check the cg (I know I should have already done that) see where in the range it is and play with throw tommorow at the field.

new2this, another thing you might consider.......if your radio has dual rates, you can set up the throws you have right now as "low rates" and then increase the throws and set them up as "high rates"......use low rates on takeoff and landing, and high rates in the air.

Mike

I wish I had duel rates. The Aplha trainer comes w/ a JR Quattro. It's a nice radio, but definetly a beginners radio. Thanks for the thought.

whatever the mod do it a bit at a time. especially when moving the CG back as a tail heavy plane is a handful.

sometime when the flying season is upon us in NJ I plan on doing an article on converting a trainer into a "second plane" including moving The CG and increasing throws.

right now the Avistar trainer that I plan on doing this to is waiting for a test flight for another article so if it survives I will be using that.

... also, more throw doesn't necessarily mean more control surface effect. It might mean the opposite if, for instance, the elevator moves so much that all it does is create more turbulence around the tail.

... also (sorry!) this is unlikely to happen with a trainer, but excessive elevator movement can make the model snap. That is, roll over on its back when move the elevator quickly and you least expect it!

David C.

Well I went out yesterday and the throw increase on the elevator made for some tighter loops. The rudder didnt really make a difference as I already had it at mid throw, just took a little less trim on the radio to keep it straight. All in all it is a trainer and there is not a whole lot I can do to make it very quick. Tonight I am going to adjust the ailerons and see if I can get a faster roll rate. Thanks all!

If your hinge gaps are not sealed, seal them. That alone could greatly increase your control surface's performance.

How small should the gaps be? There is a small gap, but I didn't think anything of it.

They should really only be wide enough to slip a sheet of notebook paper through.


Mike

Alright, looks like I will be adding some covering tonight.

Make sure that any slop in your linkage is eliminated before you fly. Sloppy linkage will have more of an effect as you move the clevis closer to the control surface.

Hey new2this, let me know what happens when you give the ailerons more throw. been thinking about doing it to mine but haven't had time....you can give me a PM or e-mail.....thanks spooner

Will do, going out today in the afternoon.

I don't know your plane but on all my Tower hobbie trainers I have all the throws set for as much as I can get.
I let a young boy solo one of them today and he had no problem.
I did replace all the control links with metal ones to play it safe.
All 4 of mine fly very nice
Just my 2 cents

I am interested in increasing my rudder throw on my World Supersport .40. If I move the clevis closer to the control surface it lengthens the control link.

However, doesn't it then require you to recenter the surface either by trimming or by manually trimming (resetting the linkage on the servo)?

So, aren't you back to square one again? Using the outside hole on the horn makes sense, or making sure your horn is setup for the neutral of the servo also makes sense to me to lengthen your throw.

I just don't see how moving the clevis out will lengthen the throw.