SENZA

Ok i flew my extra 300 today and its my first low wing, im not looking to do tricks with it just yet,but a couple of times i found my self over steering it with the sticks the plane is touchy,my question is i would like to soften the throw a little and making it a more gentle flyer and i was wondering what is a good general setting in my expos to start with. also if people use D/R for take offs and landings or do some of you use it for higher speeds.also would i make my expo settings in my high rates or low rate settings....thanks in advance..........BILL

David Cutler

Bill,

You shouldn't need much movement of the control surfaces to get good performance from an Extra; especially the elevator, as they tend to be very pitch sensitive.

About 40% (that is minus 40% on a Hitec) is about right to get a good amount of exponential to make the middle of the stick movement noticeably less sensitive.

Don't overdo it though, as at higher percentages, the last few degrees movement can get very sensitive indeed!

-David C.

Geistware

My Feedback: (16)

I would recommend that you not worry about multiple settings on your controls and learn to fly the plane on the minimum throws allowed. Once you get comfortable with the plane, you can have multiple rates on the controls.

ukrconsul

My Feedback: (1)

I suggest to try 15% of expo first (+ on JR and - others) on your plane and increase it step by step until 25% or 30% everywhere until you get comfortable with your plane. It's definitely will give you better feeling. Don't bother with dual rates now. You will be comfortable with your plane at the recommended (by manual) rates and 25-30% expo. Don't be afraid. If you can fly your plane now you will fly it better with some expo.

siclick33

I agree ukrconsul. 15% should be a good start (provided that the model is not so twitchy that it is too difficult to fly. If so I would reduce the throws a little too).

The trouble, as indicated by david cutler, of using expo as high as 40% is that it can produce a step. Control is lovely and soft around neutral but when you get near the ends of stick travel the servo has to make up for this lack of movement by going to full deflection very quickly.

I would suggest. Get the model flyable with the throws. Forget dual rates. Start at 15% and work up.

SENZA

thanks you guys for the replies the plane flys well infact a good freind of mine who flys a funtana took it up for me and was very impressed he flew it with no troubles at all the plane flew great we added just a little trim for elavators,im just new at low wing planes and maybe this wasent the best move i made buy buying this as a first low wing but i own it now! i do well with it but i still have the begginers stick twitching sindrome. infact i find flying my low wing is easier than my trainer as far as staying were you put it its not all over the place in the wind, im just intrested in flying scale right now the settings for scale on this plane were 3/16 up and down on the elavators witch i have set on my low rates but im afraid to use them due to if i get myself in trouble i dont have as much throw to corect myself so for now i would like to use the high rates 1/2 up 1/2 down for response purposes but i just wanted to soften the throws.......thanks again.........BILL .........I WILL START WITH THE 15% and lower them ias i progress

CheezeyPoof

Yeh, start off with 10 or 15% neg. Fly it a few times until you comfortable , then increase it a bit more. If you go straight to 40-50%, your going to be in for quite a ride. Your wanting to turn that plane and its not and your pushing that stick over and over to the side and nothing until your almost to the stops. Now this is fine when you have gotten use to it but whoa baby if you do it all at once.[sm=drowning.gif]

FHHuber

I never use reduced throw on dual rates. My dual rate switch just changes from no exponential to whatever amount I have determined is appropriate for the aircraft. (I have gone as high as 50%)

I have never experienced the "step" with high exponential settings... It may just be the radio that I use doesn't have that tendancy, but instead has a true exponential curve response. It may also be that I ALWAYs center up all trims mechanically, so the exponential is not offset from center of stick.

For the Extra, when advancing to it from a trainer or docile sport aircraft, I would start with 20% or maybe even 25% expo.... but again... I would have the dual rate switch able to remove the expo in flight.

The expo is for smoother flying at high speed or when taking off and landing.

I never want to be caught not having full throw available fr emergency maneuvering. But when I am flying at high speed, I don't want a tiny shake of my hand to make the aircraft jump around. That is the correct use of expo.

randy41

I dont use expo or dual rates and never have.
I would recomend to learn to fly with out them.
Just learn to be easy/smooth on the sticks and
i guess if you caint/not willing to do that then
try the expo.

David Cutler

One of the main reasons for using dual rates is to make a model handleable by a novice. A Sig Somethin' Extra, for instance, is easy to fly, BUT only if the ailerons have been de-sensitized somehow to make it not easy, but POSSIBLE for a newcomer to fly it. The same for a model that tends to snap with excessive elevator movement (like a CAP).

I agree ideally we shouldn't have to use lower rates, but if a novice wants to make the step between a trainer and an aerobatic plane it's probably necessary.

Put it this way. If I was to choose between crashing a new plane 5 seconds after take-off or arranging the controls so that I managed to fly for long enough to get 'over the hump' and learn enough abouts its characteristics to exploit its possibilities, I would choose the latter!

-Dave

siclick33

In which case, why use dual rates?

Why not de-sensitive the controls by reducing the throws and add a little expo?
Now there are no switches to throw in flight and you can concentrate on flying the model.

Just my own personal opinion. (and quite rightly in this hobby, opinions do vary)

Montague

I generally agree with the idea of not using duel rates when learning an airplane. You can get in to trouble if you get the wrong rate switch in the wrong spot at the wrong time. I've seen guys snaproll in to the ground because they were on high rate elevator at the wrong time.

As for rate switches being useful, if you are doing some of the advanced maneuvers, they are pretty much manditory. My Cap had big throws on the elevator, rudder, and ailerons. If I tried to land that thing on high rate elevator, a snaproll in to the ground would be almost certain, and that's WITH 50% expo. But that high elevator throw was just the ticket for a good blender or lomchevak. So I took off, flew most maneuvers, and landed all on low rate elevator. I only used high rate for some specific maneuvers when I needed the extra throw.

As for expo settings, I do actually use a lot of expo, as much as 55% on some of my planes. I've also not noticed a sudden step, but even so, I'd probibly start with around 25%. Much below 25% and I'm not sure the expo is doing enough to be noticed much at all.

Since you're not at the point where you're doing those maneuvers, I'd say tune down the control throws a bit, dial in a tad of expo, and go fly, and don't worry about the swtiches for now.

David Cutler

So that the normal throws are available if you want them. I do, however agree that this introduces something else that can go wrong for a novice which may not be a good idea for a complete novice!

-David C.

MHawker

My Feedback: (16)

Personally, I don't like exponential. I do have dual rates, but I like very sensitive sticks. It's easier for me to fly knowing the surfaces will move the same relative to stick movement.

I've flown my friends JR and planes (I fly Futaba) and he has expo dialed in. It's very weird... but that's just because I'm used to my way. When he flies my planes, he knows they are going to be more sensitive than his..... at first.

Geistware

My Feedback: (16)

THis is my exact recommendation.
Most people don't use 3D throws when they fly unless they are doing 3D maneuvers. Why waste the precision of the servo just to say you can move your control surfaces a ton!

irussel

Actually, the best reason to use expo is because without it, control surfaces are more sensitive around the midpoint than the endpoints. The reason is because the pushrod to servo connection travels in a circle rather than a straight line. A little expo (15-20%) will make the movement of the control suface smoother across the entire range without being 'sluggish' around the midpoint.

irussel

David Cutler

This is true, but, of course, the opposite happens at the other end of the pushrod, so the movement is more or less linear!

(bet that starts a noisy discussion!!)



-David C.

irussel

I guess the question is...does the effect at one end completely offset the effect of the other end? Gonna have to break out the compass and protractor and take some measurements...

David Cutler

If the angular displacement at both ends is the same for a given movement of the pushrod (that is, the hole the pushrod uses is the same distance from the hinge line at both ends) the control surface should (should!) move through the same angle as the servo arm throughout the whole travel, even though,as the angle changes, the actual angle it moves is not constant with the pushrod movement.

Probably!

-David C.

Geistware

My Feedback: (16)

Most mechanical variation can be addressed with your transmitter.

MHawker

My Feedback: (16)

I've changed my mind....... I don't use Expo 'cuz I hate math.

David Cutler

Sounds like a good reason!

[sm=spinnyeyes.gif]

-David C.

jcflysrc

My Feedback: (50)

That's when I think it is doing what it's designed for. I only use a bit, maybe 10-15% and it definately helps. Fly for a while at 10% and then go back to NO expo and tell me you don't notice it.[sm=idea.gif]