Total newb just trying to maiden my Simple Cub!

[InsatiableAmos]

You've been warned about inappropriate behaviour on the forum before, so leave my appendage out of this.

I've snapped several of the broad-bladed black props that come with the powerpacks through flite test, but the grey APC props seem WAY sturdier (and maybe need higher RPM to provide similar thrust despite identical measurements...?)

With all this tiny trainer talk, have any of you built the tiny trainer polyhedral wing but modified it to add ailerons? I'd love to give that a try in an attempt to preserve lazy glider-like behavior and retain aileron control authority...

 

[Monte.C]

I've snapped several of the broad-bladed black props that come with the powerpacks through flite test, but the grey APC props seem WAY sturdier (and maybe need higher RPM to provide similar thrust despite identical measurements...?)

With all this tiny trainer talk, have any of you built the tiny trainer polyhedral wing but modified it to add ailerons? I'd love to give that a try in an attempt to preserve lazy glider-like behavior and retain aileron control authority...

I feel like I've seen this question come up somewhere else recently...
Anyway, I don't definitively know the answer but I can't see why it wouldn't work fine for you.

 

[TheFlyingBrit]

Gives you the option for bigger batteries, using the same battery mounting with the glider nose and a fixed motor mount you can use a folding prop option.

 

[TheFlyingBrit]

It will work with the standard wing design using dihedral instead of polyhedral, you can also increase the wing and tail area. I put a little dihedral on my Bushwacker to improve the flight characteristics, that works fine with ailerons.

 

[Monte.C]

It will work with the standard wing design using dihedral instead of polyhedral, you can also increase the wing and tail area. I put a little dihedral on my Bushwacker to improve the flight characteristics, that works fine with ailerons.

Tell me why it wouldn't work on a polyhedral wing.

 

[TheFlyingBrit]

Tell me why it wouldn't work on a polyhedral wing.

When you implement the aileron and the plane banks, the polyhedral will be fighting to correct and right the plane at the same time. Which I would expect make the plane un-stable in the turns.
When you make an aileron turn you need the opposite aileron to right the model afterward. However, with a rudder turn on a 3 channel when you release the rudder the plane rights its self.
If you have too much throw on the Old Fogey it starts to Dutch roll from side to side and its not pleasant to fly. That's because the wing is trying to correct the imbalance but over corrects and visa versa, hence the Dutch roll. I found that out on my first flight with that plane, reducing the rudder throw made the turn more gentle so eliminated the Dutch roll.

 

[TheFlyingBrit]

 

[TheFlyingBrit]

Tell me why it wouldn't work on a polyhedral wing.

 

[Monte.C]

When you implement the aileron and the plane banks, the polyhedral will be fighting to correct and right the plane at the same time. Which I would expect make the plane un-stable in the turns.
When you make an aileron turn you need the opposite aileron to right the model afterward. However, with a rudder turn on a 3 channel when you release the rudder the plane rights its self.
If you have too much throw on the Old Fogey it starts to Dutch roll from side to side and its not pleasant to fly. That's because the wing is trying to correct the imbalance but over corrects and visa versa, hence the Dutch roll. I found that out on my first flight with that plane, reducing the rudder throw made the turn more gentle so eliminated the Dutch roll.

Thanks. Sure I get it. But everything's relative, I'm just saying. Polyhedral and dihedral wings are hardly two different creatures. We could build a dihedral wing that has a certain correctional roll effect depending on the wing angle, and we could build a polyhedral wing with exactly the same effect if we got the angles just right. People get into asking which wing has more or less of this or that, but I believe that question might only get correctly answered in some higher level aeronautical studies, and might not have much difference for our models. Show me a polyhedral wing and I'll show you a dihedral wing with pretty much the same characteristics.

I'm no expert but I imagine the poly one could be more "slippery" in roll - easier to roll, or easier to roll back past neutral like you said, in which case I would want to reduce aileron throw. Your ailerons will be at a greater angle from horizontal at level flight, but I don't see that having any obvious effect on flight characteristics.

Is it just the "slippery" bit that's the thing here? Maybe that's it.

 

[Mr NCT]

When you implement the aileron and the plane banks, the polyhedral will be fighting to correct and right the plane at the same time. Which I would expect make the plane un-stable in the turns.
When you make an aileron turn you need the opposite aileron to right the model afterward. However, with a rudder turn on a 3 channel when you release the rudder the plane rights its self.
If you have too much throw on the Old Fogey it starts to Dutch roll from side to side and its not pleasant to fly. That's because the wing is trying to correct the imbalance but over corrects and visa versa, hence the Dutch roll. I found that out on my first flight with that plane, reducing the rudder throw made the turn more gentle so eliminated the Dutch roll.

Eliminate Dutch rolls?!? I love Dutch rolls, especially the ones with cinnamon and that runny icing.

 

[Monte.C]

Eliminate Dutch rolls?!? I love Dutch rolls, especially the ones with cinnamon and that runny icing.

Yes! In Eastern Pennsylvania I knew where to find a spot with THE best cinnamon buns, made by the Pennsylvania Dutch. You would not believe.

 

[sprzout]

All went well! Got it back in the air about a week later and succeeded in landing gently enough to not require any further repairs, but cut the session short due to high winds.

Learning! Going to build myself a tiny trainer to fly alongside this and see if it's any easier/simpler for some of the smaller fields around me.

You also learned a lesson not to fly in high winds. There's a point where you SHOULD fly in some wind, so you learn how to anticipate how the plane will get pushed around, updrafts/downdrafts/headwinds/tailwinds, that sort of thing; but, one of the biggest lessons I see so many beginner pilots make mistakes on is to try and fly when winds are gusting stronger than what their skills and electronics will allow them to handle.

It is PERFECTLY ok to step back and say, "I'm not going to try flying in 25+ knot winds. I'm not ready for it." But don't let it hold you back as you get better at flying unless your plane simply won't fly well in strong winds (say, for example, if you're flying a little Mighty Mini Corsair or Tiny Trainer - they just don't have the weight or oomph to fly in that.

 

[TheFlyingBrit]

You also learned a lesson not to fly in high winds. There's a point where you SHOULD fly in some wind, so you learn how to anticipate how the plane will get pushed around, updrafts/downdrafts/headwinds/tailwinds, that sort of thing; but, one of the biggest lessons I see so many beginner pilots make mistakes on is to try and fly when winds are gusting stronger than what their skills and electronics will allow them to handle.

It is PERFECTLY ok to step back and say, "I'm not going to try flying in 25+ knot winds. I'm not ready for it." But don't let it hold you back as you get better at flying unless your plane simply won't fly well in strong winds (say, for example, if you're flying a little Mighty Mini Corsair or Tiny Trainer - they just don't have the weight or oomph to fly in that.

The key to flying in wind is keep your model up wind, once its travelled any distance down wind you will struggle to to get it back specially with a light model as Mr Sprout pointed out. Steady strong winds are not as much of a problem as you would think, its gusty un-predictable winds that catch you out.

 

[TheFlyingBrit]

Thanks. Sure I get it. But everything's relative, I'm just saying. Polyhedral and dihedral wings are hardly two different creatures. We could build a dihedral wing that has a certain correctional roll effect depending on the wing angle, and we could build a polyhedral wing with exactly the same effect if we got the angles just right. People get into asking which wing has more or less of this or that, but I believe that question might only get correctly answered in some higher level aeronautical studies, and might not have much difference for our models. Show me a polyhedral wing and I'll show you a dihedral wing with pretty much the same characteristics.

I'm no expert but I imagine the poly one could be more "slippery" in roll - easier to roll, or easier to roll back past neutral like you said, in which case I would want to reduce aileron throw. Your ailerons will be at a greater angle from horizontal at level flight, but I don't see that having any obvious effect on flight characteristics.

Is it just the "slippery" bit that's the thing here? Maybe that's it.

I feel an experiment coming on here ? build a model with both wing types incorporating ailerons and see which performs best.

 

[Hai-Lee]

Dihedral was to functions or uses, one is to bring the centre of lift in line with the centre of mass thereby providing extremely neutral handling, (the same applied for anhedral where applicable).

The real difference between dihedral and Polyhedral is that as the fuselage rolls the change in effective lifting wing area per degree of roll is greatest with polyhedral, (unless you have a ridiculous dihedral angle.
Adding ailerons to strong dihedral or polyhedral wings seems like a good solution BUT apart from the polyhedral opposing the effects of the ailerons and causing very large barrel rolls there is something to remember.

When you use ailerons on a polyhedral wing there is normally a yaw effect from the wings themselves. Try mixing ailerons and rudder together on a flat wing bird and then try to do a roll!

Many people complain of dutch roll but still maintain a rudder only turn! I teach my students that the rudder banks the model and they should drive the turn with the elevator. When you rudder turn only the lifting area of the wing is decreased and so the plane will start to slip sideways and lose height. This can trigger a loss of lift, (or stall), on the lower, (and slower), wing, the nose dropping due to gravity and hey Presto - Dutch roll! Adding elevator increases wing angle of attack and thereby increases lift so that the overall lift amount and height are retained.

A benefit of the teaching of elevator to turn is that my students do not have to learn two different methods of control, they only need to adjust their control input levels according to what they are flying.

Just what works for me!

 

[Monte.C]

I feel an experiment coming on here ? build a model with both wing types incorporating ailerons and see which performs best.

Darnit that's the smartest thing I've heard all night.

 

[bisco]

I've snapped several of the broad-bladed black props that come with the powerpacks through flite test, but the grey APC props seem WAY sturdier (and maybe need higher RPM to provide similar thrust despite identical measurements...?)

With all this tiny trainer talk, have any of you built the tiny trainer polyhedral wing but modified it to add ailerons? I'd love to give that a try in an attempt to preserve lazy glider-like behavior and retain aileron control authority...

that's my next project! i'm goingto reduce the wingspan to around 34"as well. should be a fun experiment.

have you considered the aura 5 lite stabilizing gyro? josh puts one in a cub in a video. i put one in an ft duster to learn to fly lower wing plane.
it's a great aid. you can start in beginner, where the plane flies itself and you steer, then switch to intermediate which allows some pitch and roll but no flipping. when comfortable, you can try expert which puts you in complete control, but still buffers the effects of wind to an extent.
the great thing is, you can flip a switch while flying if you get in trouble, and the gyro takes over.

 

[TheFlyingBrit]

I’m going to try to take an intermediate position on this. I can understand wanting a computer to deal with the wind and stabilize a delicate plane, but I wouldn’t use it as a beginner, because then you’re learning to fly within the software’s “flight envelope” and not the plane’s. Again, I can see the benefit to an experienced pilot who wants to safeguard their model, but Flitetest planes are so relatively cheap and easy to build, I don’t think it’s worth it.

I think a downvote button is a bad idea. You shouldn’t penalize people for using flight stabilizers, you should try to talk to them and politely convince them of your view, not threaten to cancel them. “Downvoting” is just a way to add more negativity to the forums. This forum is the most positive and welcoming place I’ve found on the internet, I think because everybody shares the passion of flying planes. We should keep helping each other out, no matter if someone uses Spektrum or OpenTX, or an Aura or not.

I can see your "Its nice to be nice" political correctness point. However, what on gods earth is wrong with disagreeing with someone or having an opposite opinion. Its like political correctness takes away freedom of speech.
I wasn't offensive or made any derogatory remarks, I voiced an opinion that for learners flight stabilisation and flight controllers are not a good way to learn. I still think the down thumb is a good idea, but obviously don't use the term "Dis-like" you have a thumbs down with "Dis-agree". Lets face it even political parties allow an opposition to provide a counter argument un-less its a dictatorship where people are not allowed an opinion or freedom of speech.
The option would have allowed Mr Flyingshark to give me the thumbs down, trust me I wouldn't have got upset about it

 

[InsatiableAmos]

...and now back to our regularly-scheduled programming...

I built a Tiny Trainer w/ the polyhedral wing (stock, without ailerons) a week or two ago and took it out for its maiden today! Success!

It was a little windy which scared the crap out of me, but after forcing myself to keep flying despite the nerves I successfully racked up ~10min of flight time (2 flights) without a crash. Woohoo! I even throttled back and almost got it down to a ground speed of zero with a headwind...lots of fun and definitely a bit slower/easier to fly than the Simple Cub. Only reasons I didn't keep going was that the gustiness seemed to be increasing and I would've had to car-charge a battery to get it back in the air.

Here's the video:

 

[bisco]

well done! if i could fly like that, i'd give up my day job