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Old Oct 13, 2012, 03:08 PM
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Spent several days trying to duplicate the control mix that I use on my Kangaroo delta wing. It too has a center elevator and the 2 outer aileron surfaces. I programed a mix so that the 3 surfaces move together in the elevator input.
After getting more frustrated because the left aileron wasn't doing what it should no matter what changes I made, I then discovered that the left servo either is made reverse of has a reverser added into the wire. For the present, I will use the standard control setup. Later I will experiment with adding another reverser to the wire to get the mix I want.
I'll say again that this is an excellent airfoil. Bill Evans used a similar airfoil in his very successful line of Simitar flying wing designs. With the optimum balance point and motor downthrust, the elevator should need little or none uptrim and the plane will fly without pitching with power changes.
I would like comments from anyone who has setup dedicated for gliding and anyone dedicated for power flying. The glider can use a lighter battery since it has a short burst to get up to altitude. The power plane needs the heavier battery for conventional flying.
I will paint the bottom with Rustoeum Plastic spray paint. It is made for resin outdoor furniture and works 1/2 way well on EPO if the surface is wiped down well with 90% alcohol.
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Old Oct 17, 2012, 12:00 AM
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Gary, IN, USA
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Ready to balance and fly.
* None of the control horns have the correct size holes for the pushrods.
* The Rustoeum spray paint went on the bottom of the wing OK. However, Duratex acrylic enamel being brushed onto the bottom of the fuselage acted like it was being applied to wax paper. A good cleaning with 91% alcohol failed to remove the mold release from the surface.
* There is some difficulty knocking out the obstruction in the wing to slide the wings fully on the tubes.
* Haven't put it on a scale but the plane feels too heavy.for a glider.
* Hooking the servo wires together and stowed in the fuselage is not easy.
* Will take it for show-n-tell at the club meeting tomorrow and will hear what the glider guys have to say.
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Old Nov 04, 2012, 09:04 PM
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Guys, remember, its rubber

Wings have a problem with wing twist...in the air.

Okay so what holds the weight in the nose up in a glide? The trailing edge of an elevator of a tailed plane....

Elevators are TINY but that's because they have that long lever to work on the keeping the nose up.

Wings don't have any lever, so a LOT of air force is on the trailing edges of the wing.....rubber wings...and even flexier control surfaces since they are thin.

Airspeed increases the down force on those edges. Fly it as a foam toy glider and likely it will be fine, but bring the speed up and wing twist will take effect causing the model to tuck.
Even if you capped the surfaces with glass or carbon the wing is still.....wait for it........rubber.

I bought one even though I hate motors in the noses of my sailplanes. It should make a nice addition to my Hawk.

For the most part, foam airplanes are limited to 50" span unless the foam gets really thick...but even then the surfaces are still ...wait for it....rubber.

Keep the airspeed down and soar...and likely it will be fun. Should be cool on the slope too. KEEP batteries SMALL to keep the wing loading down and you'll have less wing twisting going on too.

Remember the difference between an electric launch sailplane and an electric powered airplane with long wings.....the electric launch sailplane pilot only brings one battery to the field for a day of soaring :-)
Gordy
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Old Nov 06, 2012, 04:10 PM
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Pioneer Glider

I just got home from maiden flight on my pioneer glider. I got mine from readymaderc.com and got the kit for 49.99. I used an eflite 480 outrunner with a 40 amp esc, 2200 mah 3 cell. I set the cg to about 25mm aft of inboard leading edge. I think the motor is a little under powered and required me to put receiver where I think the battery should go and battery where the receiver should go to get it to balance. I am going to install a larger ( heavier) motor and see if I can put the battery aft and receiver forward and cure the underpowered situation.I used 2mm up on the ailerons and about 7mm up on elevators as per the instructions. The first launch it skimmed the grass before I got it pulled up but flight went well after that and had to trim it up during flight. Second launch went much better with trim set from the first flight. I would say for first flight you may want more like 10mm up on elevators.I will try to move the cg back to 30mm aft next time I fly it and see how that works out. Seems from other post that the cg is the key on this aircraft and the 40-42mm the plans call for is way too aft. It glides very well and requires a long flat glide to land. Drops a wing on stall so be carefull on slow speed low turns. I did a few loops and rolls with it and it requires you to get the speed up and on the loops had to add lots of right aileron to keep it from turning.
This airplanes doesn't seem to do anything great but looks cool and didn't break the bank and might be ok next summer in the thermals. Will post again after I stick the big motor in it and move CG aft 5mm.
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Old Nov 06, 2012, 10:29 PM
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"40-42mm the pland call for is way too aft"

Remember its rubber...so when you have one dot more lead in the nose than is needed to make it fall forward, then it will need more up elevator in order to keep the model from falling forward and nose down.

So with the rubber elevators battling their butts off to hold up that extra lead, when in a turn centrifugal forces on the nose going around a circle are pulling extra hard...that means the elevators need to go up even more.... and bend even more...at any point when the airforce on the rubber elevators lets off, then they pop up to where their horns are being held by the servo.

Balance is critical on wings because they don't have that long lever wayyy in the back to dampen pitch.

Remember this....airspeed empowers tail feathers...so...if you give your Pioneer a hard FLAT toss, it should rise, NOT nose up. If it noses up, you have too much up trim.

Pull some lead and toss it again. Once satisfied that it is not nosing up directly on the toss, then give it a flat toss and keep it off the ground, it is the last 2 feet of the glide that is important....it should not come to a stop in flight, then drop its nose...it should simple settle onto its belly when its airspeed dies off.

I get mine this Friday and its supposed to be amazing weather here in Kentucky, so I should get a chance to do some flights.
Gordy
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Old Nov 06, 2012, 11:39 PM
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Update

Just finished changing out the motor. Turnigy 3542/6 1000 KV. That made it possible to move the battery back to the aft compartment. Now using a 12x6.5 folding prop from HK and a 38mm spinner. Just did a static run on a 4 cell 2200mah 40c Zippy battery and got 35 amps and 530 watts after 10 seconds to let it stabilize. That should help the underpowered situation with the eflite 480 motor. If the weather is good tomorrow I will fly and post an update.

Good luck on yours Gordy. What are you using on your setup? Did you get the PNF?
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Old Nov 07, 2012, 11:20 AM
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Hosed by the Nitromodels this time :-(

Yipes, I got burned bad by Nitro.

$156 shipped, with nothing but the 'kit'.

I didn't read the details that it didn't come as their usual ARF... My fault for sure, but it doesn't make it any easier to swallow. :-(

And if you try to cancel the order, the charge you a restocking fee plus the shipping both directions...close to $100 I'm figuring.

As far as what I'm going to motor it with, likely it will be something minium with a gear box since it will be only electric launch.

My 147" molded unlimited ship for ALES weighs in at 84ozs and goes up to 200m twice on a 1800mah 3 cell, using a geared motor from Tower $105 and a 50amp speed controller I picked up for $20 (Mystery brand).

The props and hub are what kills price wize, they add up to $100 shipped.

Keep us posted on your flights please!
Thanks
Gordy
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Old Nov 07, 2012, 09:44 PM
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Reply from Nitro/HobbyPartz

Okay so I submitted a 'complaint' about the price of the kit and they replied next day.

They told me that they would send me the components of the ARF for the $60 difference of the Kit to the ARF ($199)

Of course the White one is $199 and the Yellow ARF on sale for $169....argh!

Likely it will me another $25 in shipping charges and possibly something missing so other shippments to pay for :-).

I asked if they would switch me out instead of sending the parts...and I'll pay the ARF price. We'll see :-).

Big kudos to them for the next day reply in any case. Nitro and Hobby Partz does have nice stuff at good prices for the most part. This was my fault to start with cuz I got pumped up about the model and didn't read the print. :-(.
Gordy
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Old Nov 07, 2012, 09:54 PM
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Jim any more news on your ship ?

Hi Jim,
I am 'the' Simitar guy....I've flown with Bill and was involved in getting him inducted into the AMA Hall of Fame. I have built over 100 Simitars and flew a Turbine version a month or so back at Jets Over Kentucky.

The difference between this model and Simitars is one is rubber and one isn't.

So looking at the reflexed airfoil static flying it is two seperated non connected things.

The wing loading is way up on this model with motor, battery speed control and prop assembly compared to a Simitar sheeted wing...but even if they weighed the same, The sheeted wing with balsa elevons doesn't flex, even under Turbine speeds and mega weight.

I'm still kind of pumped about this thing just cuz its odd, and all the ordering snafu I caused myself just adds to the adventure :-)
Gordy.
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Old Nov 09, 2012, 12:21 AM
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update 2

I got a chance yesterday to fly the Pioneer after putting the larger motor/prop and the 4 cell batt.. I also moved CG back 5mm to 30 mm. I used the high rates this time on the launch with the trims set to the previous flights glide and it flew right out of the hand and maintained the lauch angle with no dips at all. The low performance climb is cured, it will go vertical now if wanted. I did a few dives with power to see if it wanted to tuck and as the airspeed increased it required more and more down elevator. From what I have been reading if you dive it and it wants to tuck under then the CG my be too far aft and if it wants ballon up it may be to far forward. Most airplanes want to come back to the airspeed that they were trimed at but not sure if that applies to a wing.

Towards the end of the flight the wind picked up just a little to a lite breeze and it seems to wallow a bit in yaw. I don't think it will be good in much of a wind.

I will try to remember to bring a scale home from work and weigh it but it feels heavy.

It is hard to get a good hold on the fuselage for launch, feels like an oversized ostrich egg. I had a friend launch it for me every time but will give it a try myself next time.

Keep me posted on your results when you get yours in the air, I would like to hear what you think. Maybe you can get a better handle on it than me.

Shane
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Old Nov 09, 2012, 09:19 AM
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Airspeed empowers tail feathers

But be careful to only consider balance with the motor off... That's due to the effects of motor to wing incidence.

Okay - diving the model increase airspeed, your wanted to pitch upwards.. That means your model has more weight in the nose than is needed to make it fly forward because the elevators are having to be up in " glide" to fight gravitates pull on the nose at normal speed.

The stalling you experienced with the weaker motor was caused by the same issue... Balance.

With the adds up trim to hold the nose up the weak thrust couldn't PULL the model through the drag of the up trim. As the motor thrust recovered after each stall the airspeed increased and the up trim forced the nose more vertical back to a stall the thrust could overcome with the origin motor.

Your solution works for electric powered flight just fine. Fly replace batter and fly again. But doesn't work for someone who wants to spend more time with the motor off because drag and stalls making thermaling pretty difficult.

Your at abot 30mm keep working back , remember that the supplier is usually conservative on their posted CG ranges.
Gordy
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Old Nov 16, 2012, 07:24 PM
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Get yours in the air Gordy?
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Old Nov 16, 2012, 08:34 PM
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Diving rubber

The dive test only tests stab incidence.

Airspeed empowers tailfeathers, so when you dive a plane, not only are you doing a test that is out side the normal operating speed of the model you are applying more force to the pitch controlling surfaces of a model.

In the good old days before carbon fuselages, carbon pushrods, carbon control surfaces and digital servo with high holding power....models would blow up in the air from excess airspeed.

This is a rubber model, not carbon. So like in the good old days, when you put the model in a dive, it will have to have an extreme amount of up trim in order for the surfaces to stop bending downward as the speed increases..(aero-elasticity).

IN the good old days you balanced the models 2" forward of where we balance them today, that put a bunch of up elevator into the trim, so that if the model got into a dive, picked up extreme speed, then the surfaces would only bend down to a point that still would force the nose up, keeping the model from self destructing in the air....Tucking happened when a model was balanced properly, then when it entered a high speed dive, the surfaces, tail boom, pushrods, servos would be forced beyond neutral into negative, causing the dive to increase even more.

The dive test became a norm for testing models "CG", you know the measurement that happens in a garage or on a bench with the model teetering on some nails....not flying.

Have you noticed this model is made of rubber? Balancing it so that it pulls out is a good idea if you intend to fly it around with the motor on and some down compensating attached to throttle to keep it from ballooning.

This is a rubber toy, that will never fly the same way twice, pending temperature and wind speed.

Having said that, if it is trimmed and balanced for motor off flight, you would never consider 'dive testing' it, since that kind of speed isn't part of thermal soaring. Thermal soaring is best done at the best speed that the model prefers. That is the hands off flat and level flight speed it prefers.

You can find the speed that any model prefers by simply getting it flying flat and level, hands off. Then start pushing down elevator trim, one click at a time. When eventually notice that the model has begun to nose down, add two clicks of up trim. Then learn to fly the model set up that way for optimum performance.

I have ordered the electric component supplied with the ARF version, but I'm not holding my breath as to when they might arrive. Nitro Hobby is very pleasant on the phone (after waiting more than 30mins to actually talk to someone there.) They agree with everything you say, agree to get the parts to you, then the parts may come or not. This is a new kit to them so very likey the motor, prop spinner are not in stock.
We'll see.

Still looking forward to getting in the air. If you guys are looking for a great flying wing, get the RC Eagle (original Chinese version) it looks and thermals like a hawk.
Gordy
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Old Nov 20, 2012, 11:22 AM
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Quote:
Originally Posted by Av8rshane View Post
I got a chance yesterday to fly the Pioneer after putting the larger motor/prop and the 4 cell batt.. I also moved CG back 5mm to 30 mm. I used the high rates this time on the launch with the trims set to the previous flights glide and it flew right out of the hand and maintained the lauch angle with no dips at all. The low performance climb is cured, it will go vertical now if wanted. I did a few dives with power to see if it wanted to tuck and as the airspeed increased it required more and more down elevator. From what I have been reading if you dive it and it wants to tuck under then the CG my be too far aft and if it wants ballon up it may be to far forward. Most airplanes want to come back to the airspeed that they were trimed at but not sure if that applies to a wing.

Shane
Yes, that applies to a wing. If it is nosing up excessively in a dive test, the CG is too far forward. Keep in mind how to do the dive test properly - trim for a power off glide at about best L/D speed; dive at about a 45 degree angle, and release the elevator stick. If the nose pulls up slowly, it is about right. If the nose pulls up quickly, it is nose heavy. You have to adjust the CG, re-trim for best L/D glide, and re-test.

A more sensitive test that avoids some of the issues (possible airframe flexing, etc.) with the dive test is to half loop to inverted and see how much down stick it takes to fly inverted at about the same speed as best L/D upright. A little bit of down stick means the CG is near the neutral point, which is where a plank wing like this becomes more efficient. Too much down stick, and the CG can be moved back slowly, re-trimming each time. Plank wings are very sensitive to CG position, so make the changes in small steps.

CG position is what sets the stability, which controls if, and how quickly, the glider wants to return to trim speed. Stab incidence, or in the case of a plank style flying wing, elevon position, are only for setting the trim angle of attack (AoA). They do not effect the stability.

A thought experiment to confirm this: if you have a pitch stable sailplane (CG ahead of the aircraft neutral point) with a full-flying stabilizer, does it go unstable when you apply down elevator? No, it just changes it's trim AoA. The trim AoA may be inverted if the stab is moved to sufficient positive incidence. The same thing occurs with a plank flying wing: if the elevons are deflected downward, the trim AoA changes. If they are deflected downward far enough, the trim AoA may be inverted, but the airplane is still stable if the CG is ahead of the aircraft neutral point.

Kevin
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Old Nov 21, 2012, 02:20 AM
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Hi,

I have a few questions about this glider to those who have flown it. What are the stall characteristics like? How much do severe gusts affect the aircraft's pitch attitude, and if stalled in such conditions, how well does it recover? I'm very curious about this type of aircraft, it's one of the simplest and lowest drag designs I've seen but it's pitch stability worries me.

Thanks in advance to anyone who answers
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