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EnterTheHaggis
08-17-2005, 05:10 AM
I've just purchased an Optimus 6 to use with my sail plne and park flyers. I'd like to use the ailerons as either flaps or airbrakes to shorten the glide for landings. Does anyone have any suggestions on which way togo and what other adjustments to make?

EpoweredRc
08-17-2005, 05:17 AM
I've just purchased an Optimus 6 to use with my sail plne and park flyers. I'd like to use the ailerons as either flaps or airbrakes to shorten the glide for landings. Does anyone have any suggestions on which way togo and what other adjustments to make?

Well flaps would use both ailerons to go down and Airbrakes they would go up right? Or do you have separate Ailerons and flaps on the plane?

EnterTheHaggis
08-17-2005, 05:43 AM
I just have ailerons

Jason T
08-17-2005, 11:56 AM
I've just purchased an Optimus 6 to use with my sail plne and park flyers. I'd like to use the ailerons as either flaps or airbrakes to shorten the glide for landings. Does anyone have any suggestions on which way togo and what other adjustments to make?
Ailerons down are flaps, ailerons up are spoilers. Flaps tend to increase lift and add some drag while spoilers tend to "spoil" or kill the lift of the wing and increase drag some what. If you are wanting to shorten the glide path then spoilers (ailerons up) may be better. For my high speed stuff that just have ailerons I use spoilers to force the plane down.

Just remember if you use spoilers or flaps test your settings at altitude so you will know how the plane is going to respond. Many times you will need elevator compensation to keep the model level on approach.

fdix
08-17-2005, 05:36 PM
If you use spoilers be sure to use enough throw... At least 30deg upwards. Not using enough throw will just make your aircraft faster without decreasing lift much.

EnterTheHaggis
08-17-2005, 06:11 PM
Thanks much for the advise:-)

JimNM
08-17-2005, 11:08 PM
Hello! Just checking in to make my first post here. FLAPS move down from the wing surface - increasing LIFT by adding DRAG - neither of which I want when I'm landing a sailplane. SPOILERS move UP from the wing, reducing the amount of lift generated ...and to some extent, reducing the drag caused by the airfoil pushing the air our of the way. When the spoilers are opened past a certain point, the spoilers will cause more drag from disruting the airflow than they save from reducing the lift.To use XXXerons, be they flapperons or spoilerons, you will need a 6 channel radio and 6 channel receiver, and two servos in the wing. It is not too hard to setup - and it will make it easier to get fast or very efficient sailplanes back down in the same zip code ;)

B. Thompson
08-29-2005, 04:42 AM
Provided you have a servo in each wing, I would HIGHLY recommend spoilerons. Spoilers bring a glider down by killing lift and flaps bring it down by drag as stated in an earlier post. Both work equally well. The problem comes when you misjudge your approach and see you are coming up short. With spoilerons you just retract them to their normal position, immediately get your lift back and continue on your merry way to the chosen touch down piont. Not so with flaps! Flaps create drag and to a certain degree of deflection, more lift. If you are coming up short and retract the flaps you lose all that drag AND lift. If you don't have the altitude to lower the nose and get sufficient flying speed to regain that lift you suddenly find your glider skidding to stop even shorter than you originally thought. Even if you have the altitude to recover, now you have burned it up on recovering from the retraction instead of using it to get to the landing area. I guess I have made a long winded approach to say that spoilerons are FAR more forgiving than flaperons. This is why you see very few full size gliders with landing position flaps.

EnterTheHaggis
08-29-2005, 07:49 PM
Thank you for the input. Now, does anyone know how to configure spoileron on the Optic 6? I've only been able to set up the flaperons.

JimNM
08-30-2005, 12:26 AM
To get the spoler funtion on your radio - you will need to reverse the direction of travel of chanel(s) involved, and may need to swap the servos at the RX, too. My system uses chanel 1 and 6 - 1 is the left wing, and 6 is the right. You just need to tinker with it some - luck to you.

Fly'em HIGH
JimNM

Warden
09-01-2005, 11:48 AM
Hmmm, very interesting. I've used both flaperons and spoilerons and found that the flaperons are much more efficient at slowing the plane down and getting me on the ground. Maybe I wasn't using enough spoileron. I'll have to go back and try that again.

Gordon
09-01-2005, 02:06 PM
Hmmm, very interesting. I've used both flaperons and spoilerons and found that the flaperons are much more efficient at slowing the plane down and getting me on the ground.

I've used flaperons in preference to spoilerons for the past 25 years on strip aileron equipped aerobatic ships and found the same thing. One thing to beware of whilst using flaperons is that as you droop the flaperons more and more, their aileron effect becomes less and less. Plus, you are creating a perfect adverse-yaw situation.

I overcome these two problems by arranging for rudder to couple with aileron when the flap switch is activated. I never use the flap knob or lever, preferring to use just 3-position flaps - up, middle and full - via the flap/landing system on my JR PCM10X. However, I don't fly sailplanes at present, but I can imagine that the flap knob would be useful for fine-tuning a sailplane wing in flight to match the lift conditions.

I wouldn't use flaperons with outboard ailerons because of the combined risk of tipstall and adverse yaw.

Spoilerons avoid all the above-mentioned problems.

Many EDF flyers use spoilerons on their bungee/bellyflopper jets, and I'm now playing with spoilerons to try to improve my landing accuracy with my English Electric Lightning.

Gordon

Heidelberg Germany Flyer
09-01-2005, 08:11 PM
When you use Spoilerons at 30 degrees can do you still get some control from the ailerons, or are they totally dedicated to the spoilerons and you have to use the rudder for control during the landing?

How do you turn on the Spoilerons? Is it that they appear when you turn off power?

fdix
09-01-2005, 09:04 PM
When you use Spoilerons at 30 degrees can do you still get some control from the ailerons, or are they totally dedicated to the spoilerons and you have to use the rudder for control during the landing?

How do you turn on the Spoilerons? Is it that they appear when you turn off power?
Weather you still have some control depends on several factors: the size of the ailerons, the planform of the wing, the airfoil and so onů So you will have to try.

How you use the spoilerons depends on your radio, a 3 position switch or the throttle stick, for gliders without motor, are my favourite.

What do you mean with the last part of the question?!

Heidelberg Germany Flyer
09-02-2005, 11:29 PM
I meant: I thought the spoilerons work by turning off the power.

I bought a 3 way switch so I could use them anytime I wanted to, but I think that the switch is only to be used if you have flaps or spoilers which I don't have.

I tried hooking up the switch in my transmitter to channel 5 (right aileron) but nothing happened. How do I make it work for channels 2 and 5 so I'll have spoilerons?

I'm a little confused here...

Thanks!

Gliderbill
09-03-2005, 03:09 PM
Hi to all!
Spoilers are spoilers...flaps are flaps...ailerons are ailerons. So stating, I do understand the reasons why we try to simplify life in our RC sailplanes by combining functions and thereby reducing the number and complexity of our servo systems. I have flown 1:1 scale sailplanes and can attest to the true function of spoilers when on final and their effect. True spoilers are placed on the upper surface of the wing behind the high point of the airfoil, and when opened, (raised), they REALLY spoil the air flow! Just one landing in a commercial airliner will demo that! Having flown hundreds of thousands of miles commercially, I have watched very intently the action of the spoilers, the flaps, and the ailerons as the pilot(s) operate each. With spoilers open, you still have full control of the ailerons and the flaps. Now then, with our RC sailplanes having camber control whereby we can reflex the trailing edge, we can use the "crow" position to create drag; however, as has been mentioned, you may lose some aileron function. Its all in what you have available in your Tx system. Smooth sailing to all!

Heidelberg Germany Flyer
09-16-2005, 04:03 PM
I got the spoilerons working. I installed a simple switch that now changes the ailerons to spoilerons, with a little down elevator at the same time. Turn off the switch, and everything goes back to normal. It makes an impressive landing.

Had a shocker when I tested it, though. Since I knew that flaps needed down elevator to keep trimmed, I thought that spoilers would need up elevator. I was wrong, and it sure did jump up when I hit the switch in the test.

Now, I can highly recommend using spoilerons in gliders.

Heidelberg Germany Flyer

Heidelberg Germany Flyer
09-16-2005, 04:03 PM
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quiet flyer
09-28-2005, 12:18 AM
I've just purchased an Optimus 6 to use with my sail plne and park flyers. I'd like to use the ailerons as either flaps or airbrakes to shorten the glide for landings. Does anyone have any suggestions on which way togo and what other adjustments to make?

You want the ailerons to go up as spoilers (spoilerons). Picture if they go down. The tip camber is increasing and in effect the angle of attack of the tip is increasing (relative to the root). Perfect conditions for a tip stall. Go the other way (up) and you have an anti tip stall condition and high drag for the desired high sink rate. You almsot always need some elevator correction when you apply spoilerons which you can do with spoiler to elevator mix. My planes all need some up but I understand some need some down. In any caase not too much up as you can cause a stall.

Quiet flyer

Carlos
10-24-2005, 01:03 PM
Gordon.
You have just solved a problem of mine.
Mixing rudder with the aileron function when spoilerons are activated.
THANKS !

daveh
10-25-2005, 07:07 AM
Hi, just joined and am going to enjoy this! I've had a model with ailerons that operated as flaps and spoilers. Drooping them slightly aided slow flying when looking for lift, popping them up as spoilers worked well if I was overshooting a landing, but made aileron control marginal!
I've just completed a lightweight 2.4m (8ft to you!) model with pop-up spoiler on top of the wing. When I tried them at altitude the model immediately nosed down at 45deg - barely able to hold it level with the elevator on low rates - didn't have time to switch to high rates! It will work fine if ever I get hooked in a boomer thermal, and to drop it a couple of feet to the strip if neccessary, but as I only fly it when the wind is 10 knots or less, it usually floats in happily by itself! As its my biggest OD yet, I'm pretty pleased with it!

Jason T
10-25-2005, 11:59 AM
Dave,

Welcome to Wattflyer!

2.4m sounds nice. :)

Heidelberg Germany Flyer
10-25-2005, 04:11 PM
Hi, just joined and am going to enjoy this! I've had a model with ailerons that operated as flaps and spoilers. Drooping them slightly aided slow flying when looking for lift, popping them up as spoilers worked well if I was overshooting a landing, but made aileron control marginal!
I've just completed a lightweight 2.4m (8ft to you!) model with pop-up spoiler on top of the wing. When I tried them at altitude the model immediately nosed down at 45deg - barely able to hold it level with the elevator on low rates - didn't have time to switch to high rates! It will work fine if ever I get hooked in a boomer thermal, and to drop it a couple of feet to the strip if neccessary, but as I only fly it when the wind is 10 knots or less, it usually floats in happily by itself! As its my biggest OD yet, I'm pretty pleased with it!

Dave, If you install a rotary switch on your radio you can adjust the amount of ailerons or spoilerons with a happy neutral in the middle with the same switch. (They both need down elevator, so that's not a problem)

How does it feel when you're getting ready for summer and we're approaching winter?

Heidelberg Germany Flyer

daveh
10-26-2005, 05:39 AM
Hi Heidelberg Germany Flier and all,

My aileron glider is no more since a tree jumped out and grabbed it, but my Multiplex Cockpit radio has the three way switch for operating the flaperons - love my Cockpit radio!

I've just taken a pic of my 2.4m floater, which is rudder/elevator/spoiler setup and I'll see if I can attach it...

The new aileron windy weather flier is on the building board! I'll keep you posted on it - another OD...

Doing pictures and emailing as its too hot and humid to be building today - our summer has arrived early! Came out here from UK in 1971 so I know all about European winters - much prefer our sub-tropical ones!