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Cessna182 Keeps tip stalling and nose diving |
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Jacob 
Platinum (US) USERID: 268678 Bargain Addict! 
Joined: 07/Jul/2009 Online Status: Offline Posts: 47 |
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 Posted: 23/Jul/2009 at 11:08pm |
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Bongo When I said move the CG down, doesn't mean to the nose/front of the plane, I meant down as in to the bottom belly of the plane. I think oliver want you to correct your CG longitudinally as well as laterally. Think of CG in 3D not just 2D, (Spanwise) balancing is a bit harder to do, have you ever checked it, (most people don't)? ask me if you don't know how..
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bongofirefly
Platinum (US) USERID: 219882 Newbie 
Joined: 15/Jul/2009 Location: Eatonville,WA Online Status: Offline Posts: 17 |
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Posted: 24/Jul/2009 at 9:02pm |
 Sorry Oliver I did not see you were from Germany. My wife was born In Heidleberg.
The meaning of on the money is American slang for, exact or precise.
To Jacob I have done a horizontal CG. I always do all the basics of RC flight quite often.
We have to think outside the box with this problem. I thought of one thing you
guys might know about and that is maybe I have a servo going off by itself for some reason.
I have done the standard radio check procedure but it might a more complex problem than that test will determine? Here is some theories of mine.
1) bad receiver problem to the ailerons or rudder through probably ailerons?
2) A really gittery servo on the ailerons?
3) A bad transmitter problem to the ailerons and/or rudder?
I hope I am getting closer to solving the puzzle and clearly, I need and appreciate it all
from you guys.
 Thanks again for all the support and help.
Good winds and fly days. Shawn
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Sabrehawk
Platinum (US) USERID: 41908 HobbyKing aficionado 
Joined: 18/May/2009 Location: Seattle, Wa. US Online Status: Offline Posts: 354 |
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Posted: 24/Jul/2009 at 11:57pm |
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Well be all this as it may, I will still stand by what I have said.
And no, it isnt contradictory. It is quite simply aviation fact.
But after re-reading the OP's original post a few times it seems to me that it may just come down to the hand launch itself. I have never liked hand launching, it can go so wrong due to the human error factor when throwing a plane. I also think this plane is probably way too overpowered for its own good. This over powering will produce a lot of thrust, but along with that a lot of torque, and too much torque can and will roll the plane to the left, and this is also very critical at the point at which an airplane is thrown. At this point it hasnt yet developed the speed, and airflow over it's wing and tailplane and can very easily fall prey to torque, or any other forces for that matter.
There is also the fact that if it ist being thrown straight ahead, but rather with an upward angle,(which I see many folks doing these days) it can be stalling right away. And that will leave it at the mercy of any other forces present, the most prevelant being torque.
It also may be laterally inbalanced which will also take over if insufficient airflow is acheived right away at take off. Edited by Sabrehawk - 24/Jul/2009 at 11:59pm |
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W3FJW Ron
Platinum (US) USERID: 63218 Forum Admin 
Joined: 19/Feb/2009 Location: Tacoma WA Online Status: Offline Posts: 9067 |
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Posted: 25/Jul/2009 at 4:30am |
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It's a bit expensive maybe for this problem, but if you think it might be an electronic or servo problem, this logger will let you know what's going on.
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I can only remember half of what I say.... I used to walk on water 'til I found out it was more fun sitting in the boat drinking beer Ron |
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bongofirefly
Platinum (US) USERID: 219882 Newbie
Joined: 15/Jul/2009 Location: Eatonville,WA Online Status: Offline Posts: 17 |
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Posted: 25/Jul/2009 at 7:30pm |
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Hi to Sabrehawk and W3F JW Ron. It's a small world after all I am Here
in Eatonville. Heading 23 Miles from Tacoma on HWY-7 Mountain HWY
I have a nice 10acr field to fly on right on my property.
To Sabrehawk this damn problem actually started when I had the stock
motor on it. It was not to powerful and then I added about 100g of 36 LED lights and
batteries to power them. I thought getting a bigger motor would fix it
and it did for 10 flights or so but the problem came back again even
worse. I will try a smaller prop and less power and see if you are right.
read the begining of this blog to find out all the details on my motor and plane.
I think you really know your stuff and can solve this conundrum.
 Keep on giving me good ideas if you can. Thanks Shawn To Ron I will think about getting one of those. It souds like a cool tool to
have on hand. Thanks Shawn
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Sabrehawk
Platinum (US) USERID: 41908 HobbyKing aficionado
Joined: 18/May/2009 Location: Seattle, Wa. US Online Status: Offline Posts: 354 |
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Posted: 25/Jul/2009 at 8:55pm |
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Yes indeed a small world.
 Eatonville, man you are so close to a nice club field down there that I used to belong to. The Mt Rainier Radio Control Society.
They have a very nice facility with a 300ftx40ft asphalt RWY that is just as sweet as can be.
I didnt renew this year as I have moved wayyyy up north from where I was in Renton to Shoreline. So now Im looking at Marymoor, or Cascade Family flyers perhaps even.
A view from above, onboard my Christen Eagle.
 But we all should certainly get together sometime, and I'd be pleased to see your property.
But back to the topic, I once overpowered a plane so badly that it actually had a strong pull to the right under full throttle due to the fact that it's offset motor mounting to offset torque. Well it(the mounting) offset the torque alright and well enough but the fact that the motor was so overboard on power it actually acted too much against torque and pulled to the right instead. Geez, getting that thing to turn left was scary, but if I reduced power this right pulling tendency would relax.
So yes it is possible to overpower a plane as well as underpower it.
And again, I really do dislike hand launching. The human hand and arm just cant do this consistently the same every time. I much more trust a ground take off, and feel it's much more consistent and predictale. Plus the fact that I can abort at nearly any time, even after lift off provided there's sufficient room ahead of the plane. Edited by Sabrehawk - 25/Jul/2009 at 9:00pm |
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W3FJW Ron
Platinum (US) USERID: 63218 Forum Admin
Joined: 19/Feb/2009 Location: Tacoma WA Online Status: Offline Posts: 9067 |
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Posted: 26/Jul/2009 at 3:44am |
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Yeah. Getting together sounds good some Sat or Sun (not too early though. I'm not a morning person). Drove right by you on Thur Shawn, on my way to the park to pick up my Sr pass.
One thing you might try is to find the lightest prop you can find. The lighter the prop, the lower the P factor. A low pitch prop may help some as well.
Edited by W3FJW Ron - 26/Jul/2009 at 3:46am |
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I can only remember half of what I say.... I used to walk on water 'til I found out it was more fun sitting in the boat drinking beer Ron |
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bongofirefly
Platinum (US) USERID: 219882 Newbie
Joined: 15/Jul/2009 Location: Eatonville,WA Online Status: Offline Posts: 17 |
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Posted: 26/Jul/2009 at 8:05pm |
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Alright,
 getting together would be awesome. Maybe at my place so we could all fly for free?
I too am not a morning person since I broke my back a year ago I hit the hobbies hard all night long somtimes especially if I want to finnish one stage of a project. Working on my planes keeps me from going crazy because I have to keep in the chair or be in pain and there is not much to do but watch TV.
 To Sabrehawk. Yeh,a runway would be sweet here,but real expensive. I have a good flat grassy spot to take off from but the Cessna 182 wheels are to small to do the job I think. I'm almost finished working on my new pusher plane that I put nice big fat wheels on it to roll good on the grass. I'm gonna fly her today, I hope
. It's a FLY ZONE Sky Fly 2 that I modifyed 25% bigger with a new main wing I got for the same price as the stock one. Then I manufactured the tail out of balsa to match the bigger wing and painted her all up to look exactly like the factory colors and pinstriping. I also took out the POS motor 380 brushed, and put a Turnigy 2409 180W in it and the 8.4V- 7s = in grams,with a 3s 1800 25c. Topping it of with LED system for good night flights. This plane is only about a 1000% better now!!!! To Ron and Sabrehawk I will get a test today with a smaller prop and blog back on the data. I will go down to a 8x4 and a 7x3 the motor only has 950kv but a 4s 30-40c batt.
We will rule out the prop effect I think or I will be flying with a big smile.
 Make time to fly like an eagle Shawn.
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blackhander
Platinum (AU) USERID: 249656 Bargain Addict!
Joined: 21/Jun/2009 Location: Townsville Online Status: Offline Posts: 32 |
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Posted: 26/Jul/2009 at 9:01pm |
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_popupControl(); Just my 2 cents worth, but I have to agree with Sabrehawk. Even if you have to fit bigger wheels I would just so it could ROG. It will offer the most consistent take off conditions and gives you a chance to abort if things go pear shaped early on, with a hand launch you are commited as soon as it leaves your hand, no second chances. Its definately is a curious problem, I have one of these Cessna's and it flys like a pussycat. One thought, maybe your using too much throttle at launch. Superfly's and Hyperflea's are hand launched at a 45 degree angle at about half throttle( 2:1 power to weight ). Not even thrown, you just let go. But if too much throttle is applied at launch, they basically just head straight for the ground. Not sure if that will help, but it sounds like you have tried almost everything except buying a new one and starting from square one.
If everything went to plan life would get pretty boring, keep trying mate, these things were sent to test us.
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Edited by blackhander - 26/Jul/2009 at 9:04pm |
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Witty comment pending...
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Jhon-Jhon
Platinum (CA) USERID: 201334 HobbyKing aficionado
Joined: 18/Apr/2009 Location: Quebec Online Status: Offline Posts: 252 |
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Posted: 26/Jul/2009 at 11:12pm |
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Hey Bongo, Do you have pictures of that bird? side view, top view, front,back, inside setup, etc....
The wing span, wing area, AWU,a little more spec. to see witch puzzle we are talking about. You change a few things in your setup, if you add to much weight you change wing loading and your stall speed, like they said the hand launch might be not enough.
There a nice calculator(bottom of page ): http://adamone.rchomepage.com/cg_calc.htm
It will give you an idea witch speed you need to stay in the air.
Sometime the design(structure) of the plane is not enough robuste to take to much speed, it just warp in the air, so unstable. Lets say ye have a slow flyer made for 50 km/h and you ask im 100km/h you might have problem.
JhonJhon
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