Banshee flaps

Not too bad. Broken prop and tore up silk span and the flap on the back of the wing with the control horn on is broke.

I expected the flaps would both go either up or down but not opposite (wing flap up while tail flap down) Why is this?

> I expected the flaps would both go either up or down but
>not opposite (wing flap up while tail flap down) Why is
>this?

It is the direction you want the plane to go. Dropping the flaps on the wing gives lift to the wing--makes it rise. Raising the flaps makes it sink. Same with the tail. When you want the airplane to turn nose up, you raise the elevator to push the tail down which raises the nose. When you lower the flaps at the same time it gives more lift to the wing helping the turn along. Lift on the wing makes the wing want to to up. Anti-lift on the tail (sort of like anti-matter in star trek) makes the tail go down. Wing up, tail down, plane rotates nicely.

The farther the flaps get from the cg, however, the more they can tend to rotate the wing in the wrong direction. On the one hand they are adding lift But if the center of lift is too far rearward from the cg, it will tend to turn the plane instead of lifting it--and in this case it would tend to turn it in the wrong direction...just as you probably experienced.

When you get the cg back to where it should be, you will find that it should turn very nicely with the flaps.

Just take your time and get it trimmed out before you do anything radical with it. If it is not working right, get it working right. If it needs tail weight, add it (or take weight out of the nose). If it needs tip weight, add it. If it needs the leadout position adjusted, adjust it. "Wasting" a few flights to get things trimmed out is much more efficient than having to go back and repair (or replace) the whole ship.

That's interesting Leonard, and might explain why Cary (?) was able to get his mutilated Twister to fly to his satisfaction even though he rigged the flaps to work the opposite way from normal. I think I understand now.. thanks.

Hi Ross. Where do you live? We might be able to direct a PAMPA or AMA member in your direction to give you a hand. Going solo all the way is very discouraging, I know.

>> Any suggestions on how it should handle and what will make
>>it better. I really thought having flaps on the wings as
>>well as the back would make it very menuverable.
>
>
> I would guess that the CG is too far forward. The
>airplane needs to balance about 15-18% of the chord back
>fromt he leading edge. I think this is about 1.5" or so, but
>measure the average chord and take 15% of it.
>

Another thought - the pushrod from the flap to elevator must have a "fairlead". This is a keeper through which the pushrod passes. It allows the pushrod to move back and forth, but not to bend under compression ("up" elevator). If it bows when you give it control, the elevator won't move as much as it should, and it will be really sluggish-feeling. It will be OK with "down" elevator, but you probably aren't doing a lot of hard outside corners yet.

Other things to check - the flaps and elevator need to move about the same amount in each direction, and they both need to be at neutral at the same time.

You should be getting about 35-40 degrees of movement in each direction with *full hand motion* (about +-45 degrees). If the spacing on the handle is too small, it will move a lot less for a given hand movement, and be sluggish. If the spacing of the handle is too large, the flap and elevator will move too quickly, and either be "touchy" or , if it's *way* too large, it might feel sluggish because you are stalling the wing with every movement.

I very strongly urge you do seek out a reasonably experience pilot. There are many, many, little details that really make a difference in the way the airplane flies. We can think of the big things, but without being able to look it over in person, there might be some detail we are missing that would be easy for someone right there to see.

If you tell us where you are, we can probably give you some contacts. It's a lot more fun to fly with other people!

Ross,

Having built three Banshees over the past 5 years, I would offer two suggestions that haven't been mentioned by others so far.

First, the turn will be slow if you don't have your flap and elevator hinge lines taped. All of the models I've trimed have improved their turn when the hinge lines are taped. There are several threads on this site discribing how to tape hinge lines and what tape to use.

Second, you may be over powering the model with the 6 pitch prop. Try a 5 pitch. With 62 or 63 foot lines you should be able to fly a 5.2 to 5.3 second lap.

I went back to using cloth hinges, but go full span on them. Cheap, totally flexible, wind up with a sealed hinge line. Used Sig coverall on my Chip and with minimal effort they're very hard to see.

RUSS

I'M CURRENTLY FLYING A BANSHEE AND A THOUGHT CAME TO MIND IN REGARDS TO YOURS. THE EASE OF CONTROL CAN HAVE AN ADVERSE AFFECT ON YOUR PLANE'S ABLILITY TO TURN. IF THE ELEVATOR AND OR FLAPS RESIST MOVEMENT, YOU MIGHT NOT HAVE ENOUGH AIR SPACE TO COMPLETE A TURN.

I RECENTLY EXPERIENCED THE BANSHEE OF ONE OF MY FRIEND'S PLOWING INTO THE GROUND DUE TO SLOW CONTROL MOTION. PRIOR TO MY FRIEND FLYING HIS PLANE I NOTICED AND COMMENTED THAT THE CONTROLS WERE TOO SLUGGISH OR TOO RESISTANT TO MOVEMENT. HE COMMENTED THAT THE PLANE WAS FINE AND THAT HE HAD FLOWN THE PLANE LIKE THIS BEFORE AND ASKED IF I WOULD LAUNCH IT FOR HIM. WE LAUNCHED THE PLANE AND IT FLEW TWO NICE LEVEL FLIGHTS. AND THE HE PUT IN CONTROL TO DO A WINGOVER AND PULLED OUT AS HE NORMALLY WOULD AND PILED IT INTO THE GROUND.

SORRY TO HEAR WHAT HAPPENED TO YOUR PLANE AND HOPE TO HEAR MORE ABOUT YOUR EXPERIENCES IN CONTROL LINE AEROBATIC. WELCOME TO THE HOBBY!

STEVE GRENOT:+

MORE PHOTO TO HELP RUSS.

STEVE G