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Lateral Balence Has Me Baffled

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Lateral Balence Has Me Baffled

Old 06-01-2006, 06:42 PM
  #26  
Mastertech
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Default RE: Lateral Balence Has Me Baffled

Correct Mike

When trimming and I test for this I don't care about the heading, it just doesn't matter. I'm concerned with lateral balance, rudder trim and wing incidence at this point. IMHO the best check for lateral balance is during upright and inverted stalls directly into the wind, (Always blowing 10-15 mph when you have to trim and 0 mph when you forgot to charge or the honey-do list is long). If the same wing drops in both stalls then I'll look for lateral balance.
Old 06-01-2006, 07:40 PM
  #27  
Divesplat
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Default RE: Lateral Balence Has Me Baffled

Who is Dave??

My point is the illusion of dropping a wing can be caused by wings not being square to the flight path.

For instance if flying level, and the outboard wing is slightly lower that the inboard (pilot error or vision prob) when pulling vertical it will appear as though the outboard wing is heavy and pulling the plane not vertical, but in the direction of the lower wing. The illusion is the outboard wing may be too heavy. when in fact the plane simply wasn't flying straight and level.

The same thing can be said for pulling hard on a downline, the plane will veer in the direction of the level of the wings. Again, if the pilot sees straight and level the same each time, then the plane will respond the same each time, as that particular pilot is looking at their plane the same each time. If this continues to happen, a lot of pilots will claim there is a balance/trim/building error rather than say maybe I'm not seeing the plane correctly. My flying buddy would do this on the right side downlines everytime until we finally told him to fly like it looked wrong to him. His seeing wrong, meant he was flying straight.

Today for example, in Advanced on the Goldfish, 1 +snap followed by 1/2 opp roll. I finally figured out if I don't get my wings level as a part of the snap, the 1/2 roll falls way, way off heading because I didn't see, Straight and level with the world, on a 45degree plane, once I made sure the snap was completed and got the wings all the way around, I was able to keep the same heading without much rudder, whereas before I was hammering the rudder and cursing a cross wind (my particular excuse) I was fighting the wrong problem by trying to patch the wrong thing.

I did have an AW37% Extra that would do the same thing on a Wall, It just would fall to the right at the bottom of the downline, but only on 3D rates, not on my normal flying rates so I never worried about it.

Ed
Old 06-01-2006, 08:15 PM
  #28  
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Default RE: Lateral Balence Has Me Baffled

Sorry Ed

I understand the wings level to pull vertical and pulling to horizontal from vertical and heading changes. This does not change the fact from a downward vertical pull to horizontal cannot change the way the wings end up. I'll 100% agree that the heading can be wrong if your flying a track and you start out wings unlevel. The original problem was dropping a wing on pull from vertical. Even a pull from horizontal to vertical the wings don't "Drop" out unless there's a trim problem that induced a role. One can start with wings not level and the wings will maintain true thru the pull but now the fuse isn't following the vertical track. I agree that most guys that pull vertical and find themselves off "Track" started with the wings not level, first thing they do is grab some rudder to straighten up the fuse not roll the wings, I see most guys fly with the outter wing down a bit trying to "see" the outside wing around the fuse. Agree?
Old 06-01-2006, 09:28 PM
  #29  
Dangerous Dan
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Default RE: Lateral Balence Has Me Baffled

Dick,
i am running DUA Pierless, Dual Fromeco Regulators, and DUAL Smart Fly Heavy Duty Switched, as well as a smart fly Power expander. All Wiring is 18 guage and all Connectors are deans. The servo extentions are airwild 222 guage gold plated. I agree with some of your philosopy on batteries, But feel that the problems with lithiums is more the regulators than the batteries, basically do not exceed 4 digital servos per regulator.
Also The force on the elevators at a given airspeed and deflection is the same wether your are using standard analog or high torque digitals, and the current required for the servo to counter this force does not change significantly between different servos if anything it would take less with a digital since they use a coreless motor and are more efficient. Contrarly a high torke digital has the capibility to require more current in extreme situations.

just my .02
Old 06-01-2006, 10:25 PM
  #30  
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Default RE: Lateral Balence Has Me Baffled

Yes -- current demand is a function of work -so the difference in ANY servos which will produce desired output, is efficiency -some servos can cause excessive drain -if they are grossly overloaded .
I have also found that the std HD JR leads are pretty much up to the current demand of the 8611A servos. ( one lead per servo)
However -I NEVER run a setup which loads servos to the point where they "blowback". That is baaaaad news.
Old 06-01-2006, 10:43 PM
  #31  
Dangerous Dan
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Default RE: Lateral Balence Has Me Baffled

I find it ironic that I was able to fix the wing dropping by two methods:

1. adding 11 oz to a wing tip

2. Fixing linkage problems


Makes you wonder how many people added weight when there linkages were bad...LOL
Old 06-05-2006, 09:31 AM
  #32  
JPrc
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Default RE: Lateral Balence Has Me Baffled

Went out flying this weekend with the purpose of double checking my lateral balance on my 260. I never heard of the inverted method of checking the balance but decided to give it a try. What I found was pretty interesting and helped me solve a problem I've been fighting. Upright level flight the plane is trimmed to fly hands off straight across the field with no wind but inverted the plane always rolls to the left and on downlines a left roll, a problem that I have been flying through all season. After thinking about it, this problem was evident in just about every maneuver I had in my sequence but I was flying around the problem. At the beginning of the season I initially added 3oz to the right wing tip, thinking back I am not sure why I came up with that amount, but decided to take 1oz off and see what happened. Next flight plane need 1 click right aileron trim to fly staight and level then rolled inverted and the improvement was drastic. Inverted the whole length of the field maybe a slight left roll, maybe another 1/4 to 1/2 oz of the tip. Every maneuver where the plane was inverted at some point (top of loop, laydown humpty from inverted, teardrop from inverted push, pulling around the top of a humpty) was improved with the weird roll coupling completely gone. I didn't realize how much I had been flying through the problem till it was corrected. Of all the tweaks and adjustments I have done in the last couple weeks this change made the biggest improvement. You guys may want to give it a try, I thought I had my lateral balance nailed with the downline/pull method.

Jonas
Old 06-14-2006, 10:42 AM
  #33  
toprudder
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Default RE: Lateral Balence Has Me Baffled

I'm glad you were able to fix the problem WITHOUT having to add weight. IMHO, if the plane is balanced laterally, and it has the problem you mentioned, there is something else wrong. Two wrongs don't make a "right". (sorry, could not resist).

I'm surprised no one mentioned sealing the aileron gaps. That would have been my first thought.

Straight plane (correct incidences, no warps), sealed gaps, tight linkages, matched throws -- start with the basics first. Don't try a bandaid fix.

Many years ago, I remember a guy that was having problems trimming his plane. He tried everything. Someone suggested they check the CG, so they lifted the model by the wingtips with their fingers. It was then they discovered the guy had a cracked wing and did not know it!!!
Old 06-14-2006, 11:14 AM
  #34  
Dangerous Dan
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Default RE: Lateral Balence Has Me Baffled

I sealed the gaps before the maiden, check insidences throws etc... What happened is when I was installing the outbound right wing aileron servo I had to force fairly hard to get the servo to fit. Inadvertantly I loostened the servo mount in the foam the entire servo would move 1/4" in the wing after the first few flights.

Thanks for everones input I am just Glad I figured it out and was able to remove all the weight...

Thanks again

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