I sure can't fly my Simple Soarer!

[Jtnb]

Some of you may recall my previous posts about electronics packages:
http://forum.flitetest.com/showthread.php?9585-Am-I-missing-something-Costs-of-electronics

and how to fly bank and yank:
http://forum.flitetest.com/showthread.php?10392-Simple-Soarer-almost-done-Can-t-fly-it!


Well, folks, I'm still not able to get this poor thing to fly. Here's the deal:

Built the simple soarer somewhat to design. Made power pod longer. Had to adapt to stick mount because of a wrong order (my fault) from HK. Made a stick mount from cedar with a DTFB sandwich. Works fine. Glued it in with hot glue and shimmer and supported with bits of FB.

Had a hard time balancing. Had to move the pod back and move the wings forward (removed and re-poked skewers). Finally got the bird so she was a bit nose down with the battery in place. See unorthodox installation.

Hand-tossed it a bunch of times and couldn't seem to get her to fly. Re-consulted the bank and yank thread noted above. Decided that maybe I needed to get a couple of mistakes high so I could figure it out. Tossed the glider and added power.

Four "flights" followed by immediate crashed followed. In each case the plane nosed up (still under control w/ elevator) and banked left and crashed. One cartwheel. One nose in the grass. Two others not so terrible. Damaged the elevator, but that's it.

The plane is still intact, but unless I can get something to go on here, I am going to install ailerons. I know how to fly with those. This seems hard. No amount of rudder will change the inclination to bank left. I also shifted the wing spar off-center in both directions alternately to see if moving weight to one side or another or adding more lift on that side would make a difference. No dice.

Any thoughts, o learned people?

Jonathan in Connecticut.

 

[Foam Addict]

Ah, 2 things jump out at me. One, that is a massive prop for that plane (and motor) at any RPM above around 7000. What KV and voltage?
Two, do you have a warp or slight angle in one of the wings? That can really mess up any plane, but especially a RET one.

 

[engineer]

I had the same thought about the prop size, but dismissed it since his links make reference to the recommended 8x4's.

When I had similar issues, i later discovered it was a few different things. One, I'd not calibrated my esc. Two, I was launching with throttle too low. Three, my TX antenna was loose. Result was, goes up 10-20 ft, then noses into the ground, even with full-up. Dunno if any of that will help you, but you never know...

 

[con244]

Hi Jonathon,
check your plane's geometry as well. Measure the distance from to wing tip to the rudder and make sure its the same as the other side. Also do you have an offset on your motor? When looking from above the wings at the line of the motor a offset of about 3 degrees to the left and also about 3 degrees down as well will help offset the motor torque when first launching. This is quite important on large light models like the GWS SlowStick so it may apply here as well.
Good Luck
Con

 

[MartyLJ57]

SS kit

I just got my Simple Soarer kit. Inspecting the parts I noticed that the control arms have no connectors for the control wires. The arms are cut for them but I don't see the connectors. Is this a goof at there end or do I need to purchase them?

 

[xuzme720]

The connectors are not included since it's something that most people will want to use the version they like and can get locally.

 

[Dakota_Kid]

Getting a glider to fly.

I was helping a friend out getting his motor glider going.
Look on this thread to get up to speed.
There are a couple of suggestions there that might help you.

http://www.rcgroups.com/forums/showthread.php?t=2003872

It turns out when he built the wing, one side had wash out and one wash in.
Here is an image showing washout.



Like a previous post, make sure your wing isn't twisted. It would be better to have it flat with no
washout than twisted. Washout helps to not tip stall.
Lay the inboard panel of the wing on a flat surface and make sure it is the same dimensions from
the surface to the leading edge and trailing edge out at the tip. Do that for both sides. if the trailing
edge is 1/8 inch up it is ok, but down is bad. Make sure both sides measure the same.
You could do that for both the inboard panels as well, so they are level with each other.

On my friends plane, I noticed that under power the airplane wanted to nose up, drop one wing, and stall out
which made it fall 30-40 feet before i could recover it.
When I barely used power, it would fly level. The tip dropping was caused by wash-in under power.

I would do what was suggested. Make sure it was built straight and level, balanced and symmetrical.
Have the proper cg, and do a glide test. My 2 meter glider will go 50 yards from 7 feet up and a brisk
push forward. If it don't glide, it won't fly.

Also, when building the plane check to see of the wing is level at the same time the horizontal stabilizer
is level. Some models require that the front of the wing be a couple degrees higher than the back of the wing.
That would be about the thicknes of a dime at 9 inches wing chord.
If you built a simple box fuse that had no taper, and put the wing on top and fastened it down, and also the
same with horizontal stabilizer, they would both be on the same plane or level. Then shim up the front of the
wing a 1/16 of an inch. That would be about right.

Here is a picture of a glider wing profile showing cg location and shape. It is usually 1/3 of the way back from the
leading edge of the wing and at it's thickest spot. Is your wing a similar profile. That is basically a flat bottom wing
and the thickness is usually about 10% of the chord on the average. That makes a good starter glider to train on.
A little thicker would be ok too, like 12-13%. It would fly a little slower. Not thick enough might not be enough lift.

There is 2 views of the front, one glider, and the other powered. Notice the down thrust angle on the powered.



Here is an image of a trainer showing a slight higher angle of attack on the main wing vs the horizontal stab.



Hope this helps you figure out your problem.

 

[Dakota_Kid]

I forgot to ask what your all up weight is ready to fly? It should be around 12 oz.

It looks like you got your turning sorted out in the other thread.

Also, in the pictures it shows your rudder turned a bit. Is it straight in line when you
power it up? It should be in most cases.