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Old Dec 05, 2012, 10:11 PM
The Sequel
mustflynow2's Avatar
Australia, VIC
Joined Sep 2011
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a couple of pics of the phoenix rudder
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Old Dec 05, 2012, 11:55 PM
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United States, ID, Burley
Joined Mar 2012
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Originally Posted by mustflynow2 View Post
a couple of pics of the phoenix rudder
i would think that was a definite mistake in engineering there An easy fix though..
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Old Dec 06, 2012, 01:45 AM
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I'm not an expert but I noticed immediately and decided not to fly before fixing its down part to the fusealage. A simple fix and now it's perfect.
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Old Dec 06, 2012, 08:54 AM
High Altitude Flyer
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Fairplay, South Park, CO
Joined Sep 2005
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Flying with & without a rudder on gliders- both useful

Friends,

I've done a lot of 'Bank & Yank' flying over the years, too- had a blast doing it!. For some types of flying- specifically for hard-core slope combat like we fly here in Colorado, a rudder would be a useless piece of extra mechanism that would simply add weight, drag, & vulnerability to damage.

And for hotliner / warmliner flying, the rudder has little to offer... yes, it's handy for lining up landings in tight landing sites, & other than that, mostly remains unused.

On my ~40" Me163b, I built in a rudder... when I complete the larger one, I'll omit the operational rudder completely; that's simply relative to the way I choose to design & fly each aircraft.

With the thermal hunting opportunities I have here in Colorado's high country, I occasionally go out to hunt lift, flying low level tight thermals of very modest diameter & light lift dynamics. (Above 600 feet, the whole sky seems to be going up some days... there's no challenge in staying in lift up there. It's down close to the ground where the fresh thermals are born that the real challenge lies.)

But when doing a quick climb to only 250-300 feet AGL, chopping power, & hunting the smaller tight patches of lightly rising air that you'll encounter there, your ability to stay in lift and ride it up to speck out sometimes benefits from employing different flying techniques. That's where staying in a tight column of lightly rising air calls for turning relatively tightly without dropping a wing tip much at all- if you do, you'll loose lift & drop out. In my experience, a "bank & yank" approach just isn't as effective as working with both rudder & ailerons to keep the aircraft's bank attitude flatter while still staying within the tight patch of rising air. [Try it if you get a chance- you just might find it useful...)

Deflecting a rudder slightly does produce a bit of drag... and deflecting ailerons also produces some drag (and adverse yaw in some cases, some setups). It's simply part of flight path control - options available to the pilot to use or not.

Different strokes for Different folks! - It's all fun, all useful!

VIKING
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Old Dec 06, 2012, 10:51 AM
Grau Adler
United States, CO, Evergreen
Joined Mar 2012
32 Posts
Rudder to control airspeed???

Sorry Pete,
You can do a lot of things with 3 axis control, including things that were not intended. But rudder for airspeed control, in a turn, is not one of them.
A coordinated turn is all about lift vector.
I don't type fast enough to attempt to prove this, but over forty years with my butt strapped in sailplanes, J3 Cubs, ejection seats and flying busses through the 767-300 tells me it is not so.
No offense intended but there is already too much in accurate info on the web.
Terry,
retired but not dead yet
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Old Dec 06, 2012, 12:06 PM
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I use rudder all the time on most of my planes.For lining up on runway and keeping wings level,to HELP in turns,to do a flat circle (rudder is a must) to do snap rolls, i wouldn't want to try flying many of my power gliders or 3d planes with no rudder.
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Old Dec 06, 2012, 12:36 PM
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I have a SIG Ninja slope glider... it doesnt have a rudder either
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Old Dec 06, 2012, 12:55 PM
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You are absolutely right, Terry. Just a senior moment on my part. I have corrected the post to replace speed with "attitude". Thanks for the catch.

pete
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Old Dec 06, 2012, 01:16 PM
Seeker of Thermals
botulism's Avatar
United States, MT, Kalispell
Joined Aug 2004
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Quote:
Originally Posted by viking60 View Post
...
That's where staying in a tight column of lightly rising air calls for turning relatively tightly without dropping a wing tip much at all- if you do, you'll loose lift & drop out. In my experience, a "bank & yank" approach just isn't as effective as working with both rudder & ailerons to keep the aircraft's bank attitude flatter while still staying within the tight patch of rising air. [Try it if you get a chance- you just might find it useful...)
...
How can you argue with logic like that? I hate it when I 'loose' lift.

My post had very little to do with the advantages/disadvantages of turning with rudder or ailerons. If you want to fly an incredibly large circle in the most inefficient way possible, go ahead, yaw away. My point was that Viking had said in numerous posts how poor the rudder response was when initiating a turn with the rudder. I pointed out that the Phoenix 2K has a completely flat wing, and the rudder isn 't going to do anything except yaw the plane along its longitudinal axis. It's certainly not going to initiate any turns. He listed 3 other planes that had much better response to 'initiating a turn' using only the rudder, and I pointed out that the 3 he listed all had polyhedral, which rolls the sailplane along its longitudinal axis (no ailerons needed) after application of rudder. Of course they're going to have better (faster) turn response with only the rudder.

I'm just trying to give the P2K a fair shake, as it's doing exactly what it was intended, its rudder does an excellent job.

Good day (and I mean that).

--
Greg
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Old Dec 06, 2012, 01:27 PM
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I am thinking to buy this plane, its only 65 usd ARF in EU!

1. Can I use 1600-2200kv motor with it? 1200kv seems to slow Maybe smth like Turnigy2836 brushless Outrunner 2350kv
2. Can I use a NON folding prop? Will it break durin landing?
3. How long can you glide with 2200mah 3s + 2836 1000kv motor? 20 min?
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Old Dec 06, 2012, 01:57 PM
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United States, ID, Burley
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Quote:
Originally Posted by RoboSerg View Post
I am thinking to buy this plane, its only 65 usd ARF in EU!

1. Can I use 1600-2200kv motor with it? 1200kv seems to slow Maybe smth like Turnigy2836 brushless Outrunner 2350kv
2. Can I use a NON folding prop? Will it break durin landing?
3. How long can you glide with 2200mah 3s + 2836 1000kv motor? 20 min?
This plane is VERY light ! When i first spun up the stock motor i thought there is not enough power,no way this motor will lift the plane. but she fly's great and fast ! I am using a 1600 3s lipo, hardly used any of it after flying for around 10 minutes,you need the folding prop and the brake set on esc or sure enough you will break the prop.
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Old Dec 06, 2012, 02:00 PM
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Hi, RoboSerg.

A sailplane, not a hotliner, will generally use a motor with a kv from 850-1200. One wants to be able to swing a large prop to generate thrust at low speed.

A non folding prop will generate so much drag, particularly if it windmills, that soaring will be virtually impossible.

Soaring time depends on how much current one uses with the motor. A sailplane with four micro servos will be able to run the radio for well over an hour if one doesn't spend time flying under power.
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Old Dec 06, 2012, 04:47 PM
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United States, IN
Joined Jan 2012
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Originally Posted by fastfwd View Post
sweet ! pictures ? Im loading the plane up and going to maiden it this afternoon. Got the 2.5m wings so hope she floats like a humming bird ill do the go pro video and try to keep it close enough to see, go pro isnt that good for this as it makes everything look further away


I'm not sure that foam in the can I used to fix my wings would be good for more repairs. So far it has not become rock hard. I did use it to fix my wings but I also coated the top and bottom with that spackling I bought and then covered the top and bottom with shoo goo. But I'm still experimenting with it though.
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Old Dec 06, 2012, 06:25 PM
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I'm not sure that foam in the can I used to fix my wings would be good for more repairs. So far it has not become rock hard. I did use it to fix my wings but I also coated the top and bottom with that spackling I bought and then covered the top and bottom with shoo goo. But I'm still experimenting with it though.
may be you needed to put in a little at a time letting it dry,then add a little more ect until it was built up. If it was me i would go get some foam board or find a chunk of foam at a local hobby shop and glue it in using gorilla glue,first put a bit of water on each side to be glued, then after gluing cover with tape so it cant spread to far. after it is dry it can be sanded off.
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Old Dec 06, 2012, 08:04 PM
Seeker of Thermals
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United States, MT, Kalispell
Joined Aug 2004
581 Posts
Quote:
Originally Posted by RoboSerg View Post
I am thinking to buy this plane, its only 65 usd ARF in EU!

1. Can I use 1600-2200kv motor with it? 1200kv seems to slow Maybe smth like Turnigy2836 brushless Outrunner 2350kv
2. Can I use a NON folding prop? Will it break durin landing?
3. How long can you glide with 2200mah 3s + 2836 1000kv motor? 20 min?
Hi Serg.
1. Lower RPM = more torque = ability to swing a larger prop.
2. a - it will most certainly break on landing, b - if it doesn't fold back, it's adding quite a bit of drag, not good.
3. The size of the battery is only indirectly proportional to 'how long you can glide'. How long you can glide is dependent on lots of things, mostly catching updrafts (either thermals or wind deflected upwards). I would say it would be possible to glide for days on a 2200 mAH battery pack, assuming you could catch enough rising air to stay aloft. Somewhat more difficult at night.

--
Greg
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