joco1

took my hangar 9 super stick 60 back out tonight and it still drops like a rock ,i have a os max 60 on it and i balanced it just like the manual said i added 3oz of weight to the tail to get it balanced and did the maiden last week and i had full down trim to get it to stay up and still had to hold way back on the stick ! so tonight just to see if it would help i added 2 oz of weight and didnt see much difference so i brought it back in and added 3 more oz of weight and it started to help a little it would climb too much flying into the wind and would still drop like a dang rock going down wind thats around 8 oz i have on the plane now! i have a zinger 12x7 on the front but it takes a whole lot of runway to even get airborne ! any suggestions on what im doing wrong!

Live Wire

joco1
Check the angle on your motor ! it should have a little down thrust. If not set right changing engine power will change angle of attack. Full power will climb and idle will drop like a rock[:@]

joco1

how do i adjust it ? the engine some way or the mount?

brett65

My Feedback: (18)

Put washers under the front mounting bolts of the engine or under the bottom engine bracket bolts.

Campgems

Never put washers under the enging lugs. It stresses the metal because it can't lock down flat and a medium hard engine strike can crack the lug or in an extreme case crack the crank case. Use you washers between the motor mount and the firewall to adjust thrust.

I have an old quicke 500 and I was using a 40-45 Dave Brown motor mount on it. My OS 40 ws a little tight between the lugs, but It would pull down OK. I shattered two of these motor mounts with nothing harder than a prop strike, one on a dead stick. I finally ground out the inside of the mount so the engine sat flat on the lugs without any pressure. I later took a hit that ripped the firewall out but the engine and motor mount were not damaged. Pre stressing the mount and/or engine by providing a non flat mounting surface will result in damaged that would otherwise be absorbed by the entire airframe and basicly shook off.

The wood of the firewall will easilly bend and distort, and not fail like a harder material, like the DB motor mount, or the crank case like my Saito 45 did.

Don

horace315

My Feedback: (15)

that's so strange,my super stick the last one i got is about 2 years old now and i have had two of them and they both came out tale heavy.there was an amendment that a fella brought out to the field showing where the balance point was 5/8 further back than the instructions.even that amount wouldn't be affecting yours like you say.the first one i had i added about 9oz to the front under the fuel tank.
the second one i added a fiberglass engine mount to it by dubro and also put an os91fx on it,which the weight between that engine and the 61 was almost the same.i moved the 91 out on the mount rail until i got the balance point i wanted.that's with the radio equipment moved as far forward as i could get it too.i also cut lightning holes in the vertical and horizontal stabilizers.even the first one flew with not a lot of problem it came in a little fast,the second one fly's beautifully.what you have explained sounds like to me the balance is too far back.

joco1

i see no down thrust at all it appears perfectly straight is this a common problem that i should try to fix or should i try to do some balancing at a different point the plane flys great until you let off the stick and then it just drops really fast horace if this was your stick where would you start!!!!!!!!

spiral_72

This doesn't make sense. You added 8oz of tail weight! The plane should do nothing but hover. If the plane requires 8oz of tail weight just to improve, something is very wrong.

As a guess, I think you are compounding your problems now. I think the plane is rediculous tail heavy now, with a ton of down thrust on the engine.

Check the tail and wing incidence with a long straight edge. You might find the horizontal stab is off with respect to the wing.
Second, make absolutely sure you understand where the manual says the CG is at. Sometimes it's called out from the leading edge, sometimes from the spar.
Third, get the plane high ASAP and cut the throttle upwind. With the engine at idle, it should glide, slowly losing altitude. The glide test will be very important because it eliminates the motor and thrust angle from the problems leaving only the airframe. If the plane glides at idle, you problem is the engine setup.

...or find someone that's an experienced flyer. If you figure this out on your own though, you'll have learned very valuable experience.

.....also, in a perfect world all your controls will be centered. It gives you something to strive for.

brett65

My Feedback: (18)

Just a thought, are you sure that the elevator is trimmed for level flight or is it giving down elevator when the stick is at neutral? Sounds like it needs a mechanical adjustment or something. [sm=71_71.gif]

joco1

maybe thats my problem this is the first plane ive had that called for the cg to be from the back of the main spar, it calls for 1/8 inch from rear of main spar i had to ask on here about that and got some good pics of the same and felt confident that i was doing it right but maybe i didnt ! can anyone shed a little more light on this measurement, like what it may be from the leading edge(hangar 9 super stick 60) and while we are on this subject, why arent all planes cg measured from the leading edge of the wing instead of some being from the spar? also im a newbie here but i didnt realize that you can add too much weight to the rear and make it heavy in the front like that seems like i learn simple things that are very important about this great hobby every day! i would like to figure it out myself like you said spiral it would help to learn alot more!! thanks for all the help so far!!!

flyX

well I thing it dosn't matter how big or small an object is...they'll fall out of the sky at the same rate.

spiral_72

The manual says:

An important part of preparing the aircraft for flight is
properly balancing the model. Don’t inadvertently
neglect this step. The recommended C.G. (Center of
Gravity) location for the first flights with the Super
Stick is 1/8" behind the main spar of the wing (the
main spar spans the length of the wing underneath the
back edge of the wing sheating).
If necessary, add weight to either the tail or nose until
the correct balance is achieved. Stick-on weights are
available at your local hobby shop and work well for
this purpose.

So, I like to lay the plane upside down, measure my recommended cg location on both wings. I'll mark it with a fine tipped marker. I also like to use a hot glue gun and make a small dot that I can feel. Now, I TRY to do this on a wing rib, because it gives you a surface under the covering that doesn't flex and could throw off the CG slightly.

Like the manual says: the main spar spans the length of the wing underneath the back edge of the wing sheating
So find the spar, find the rear edge of the spar (you can feel this as a corner) and measure 1/8" back. Make your mark (or hot glue dot)

You'll need a helper to hold the other wing so it gives you a better look at the plane's side and the nose / tail. I built a PVC thing with two vertical poles with a cap, so I can set my plane on it and stand back. You want the nose slightly lower than level. Use a tapemeasue. Maybe 1/4" lower than level. Add weight or move stuff around untill it balances. Do this with the tank empty if the tank is in front of, or on the CG (which I'm pretty sure it is.)

Center all your throws and center all your trims. You'll probably have to adjust the servo arms or pushrod length, if you haven't done this already.

Fill it up and launch it! Get high quick and do the glide test.

And don't worry, I learned all this junk about 1 year ago.

spiral_72

I'm not sure what you mean here, but from reading it, that's not a true statement. Adding weight in the tail (moving the CG back) makes the plane more responsive, and raises the nose to the point it's impossible to fly. While adding weight to the nose (moving the CG forward) makes it less responsive, lowers the nose, increases your stall speed to the point it falls at anything less than 100mph.

Those are extreme examples, but it gives you an idea of the tendancies (SP?) before and after the CG.

TedMo

I'm a bit late in replying to this but have to try and understand what has been said. from what I read you say you have full down trim to get it to stay up????And still had to hold way back on the stick??? Something screwy here full down trim and full up on stick??? I just can't figure this out Adding weight to tail to get it to balance where it should but countering that with down trim and full up?? I'm totally confused. Hope someone can help me out here.

GSXR1000

My Feedback: (7)

could be he measured his cg from the front of the leading edge than the main wing spar? so if only he only measured 1/8" behind the leading edge, and balanced the plane; that would throw off the recommended cg because he would think it's balanced and not have enoough weight towards the rear of the plane.

ndb8fxe

My Feedback: (1)

I think he is confused about what down trim is. It sounds like he is moving the trim lever or switch down and calling it down trim. Either that or he is pushing the lever up and expecting the plane to climb.

More explanation is needed to see what he is really doing, but you are right it doesn't make much sense the way that it was stated.

flyX

1. Try this first.....RAISE both airlerons.


2. Remove the down thrust...
Or add washer to the bottom of the engine mount.
How far forward did you mount your engine.

It's like it's nose heavy and his pulling on the sticks.

A model will naturally gain altitude as it gains lift. when flying up wind there's more air blowing over the wing..therefore more lift.
when flying down wind...there's less lift or there's less wind blowing over the wing from the front.

It's the same when you land a model ..you control the altitude via throttle...not elevator

srk866

I just made my maiden flight with my superstar 60 wednesday. Engine is an upright mounted magnum 91 4stroke. Mine wanted to nose dive a little at first but after adding 3/4 oz to tail with the specified cg it only needed about 6 clicks of up elevator to fly very nice.

srk866

Bye the way i have no up or down thrust angle on the engine just about 2 deg of right. The weight i added put the cg right about 3/4 behind the spar not 1/8 as specified. Also keep your ailerons level with the wingtips like they shoule be and subtrim a little up elevator as needed i'll could probally add another 1/4 ounce and be able to keep the elevator trimmed straight.

srk866

Just to let you know for my super stick to fly well with a 91 4 stroke up front with no up/down thrust (mount flush to firewall,engine flush to mount) I balance out at 4" 1/4 from wing leading edge .