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If you do not understand the specialized terms used to describe an airplane/glider, I suggest you do a little homework. Google 'parts of an airplane' the first hit was pretty good. We use the terms because they are a clear, consistent way to describe a plane and work a lot better than "that flat thingy at the back of the glider". Ultimately the specialized language IS the simple language.

One translation. Stab is short for stabilizer. There is usually (but not always) a horizontal and vertical stabilizer on a glider/airplane. And yes we can get a little lazy about which one we are talking about.

So, tilting the horizontal stabilizer to get turn will low drag. Add rudder to the vertical stabilizer to get turn with higher drag.

Jeff Anderson
Livonia, MI

jander14indoor wrote:If you do not understand the specialized terms used to describe an airplane/glider, I suggest you do a little homework. Google 'parts of an airplane' the first hit was pretty good. We use the terms because they are a clear, consistent way to describe a plane and work a lot better than "that flat thingy at the back of the glider". Ultimately the specialized language IS the simple language.

One translation. Stab is short for stabilizer. There is usually (but not always) a horizontal and vertical stabilizer on a glider/airplane. And yes we can get a little lazy about which one we are talking about.

So, tilting the horizontal stabilizer to get turn will low drag. Add rudder to the vertical stabilizer to get turn with higher drag.

Jeff Anderson
Livonia, MI

What do you mean add rubber? and thanks

science8 wrote:

jander14indoor wrote:If you do not understand the specialized terms used to describe an airplane/glider, I suggest you do a little homework. Google 'parts of an airplane' the first hit was pretty good. We use the terms because they are a clear, consistent way to describe a plane and work a lot better than "that flat thingy at the back of the glider". Ultimately the specialized language IS the simple language.

One translation. Stab is short for stabilizer. There is usually (but not always) a horizontal and vertical stabilizer on a glider/airplane. And yes we can get a little lazy about which one we are talking about.

So, tilting the horizontal stabilizer to get turn will low drag. Add rudder to the vertical stabilizer to get turn with higher drag.

Jeff Anderson
Livonia, MI

What do you mean add rubber? and thanks

Rudder, not rubber. It means twisting or bending the vertical fin a little bit.
I'd suggest doing as Jeff suggested and doing a little background research to understand some of the basic terminology of aviation events.

Is there a certain benefit of tilting the stabilizer versus twisting the rudder to create the circular motion? jander said something about low/high drag but does that necessarily impact the flight time significantly one way or another?

When twisting/bending the rudder (this might be a silly question but I haven't seen results either way) are you bending so that that 'bend' line is vertical or horizontal.
Couldn't think of a good way to verbalize it, so that when you bend, the line that makes if you were to continue bending to break, is it vertical so that part of the rudder isn't straight with the fuselage or horizontal so that the rudder makes an angle to the left/right of the fuselage?

Should i do all three bend the rudder, tilt both stabilizers? Or can i only do 1 of them? which one is the most effective?

mrsteven wrote:Is there a certain benefit of tilting the stabilizer versus twisting the rudder to create the circular motion? jander said something about low/high drag but does that necessarily impact the flight time significantly one way or another?

When twisting/bending the rudder (this might be a silly question but I haven't seen results either way) are you bending so that that 'bend' line is vertical or horizontal.
Couldn't think of a good way to verbalize it, so that when you bend, the line that makes if you were to continue bending to break, is it vertical so that part of the rudder isn't straight with the fuselage or horizontal so that the rudder makes an angle to the left/right of the fuselage?

Yes, there is a benefit of tilting the stab over using the rudder. Several.
At high speeds the rudder is more effective in turning, ie it effects the launch when you don't want aerodynamic turn.
At slow speeds, most of the flight, the horizontal stab is more effective in causing turn (smaller input to create same turn). It is also lower drag. And lower drag is absolutely important to glider duration.

Adding rudder is done by bends to the vertical stabilizer. The bend should be along its length or vertical. Think of the hinge line on a full size planes vertical stab to the rudder.

science8 wrote:Should i do all three bend the rudder, tilt both stabilizers? Or can i only do 1 of them? which one is the most effective?

Basic principle in experiments, unless you know how to handle designed experiments, one change at a time. Otherwise how do you know which factor made the difference. See above for which is most effective, when.

Jeff Anderson
Livonia, MI

you say it is beneficial to tilt the stab before the rudder. Which stab are we talking about horizontal or vertical? or does that not matter? Which is better to start with?
Haha i used a little vocab nice

science8 wrote:you say it is beneficial to tilt the stab before the rudder. Which stab are we talking about horizontal or vertical? or does that not matter? Which is better to start with?
Haha i used a little vocab nice

The vertical stabilizer is the rudder. The horizontal stab is well... the horizontal one. Take a look at this image: http://goo.gl/iup19 . Mr. Anderson is saying that it would be better to bend the horizontal stabilizer, and not the rudder/vertical stabilizer. Tilting/bending the rudder has always been easier for me, and it's probably a good place to start for the beginner.

I mean tilt the horizontal stab. Hmm, maybe I need to explain tilt. The left tip of the stab is higher than the right tip (or vice versa depending on which way you want it to turn, which mildly depends on if you launch left or right handed) when compared to wings level. Typically done when you build the glider. IF you need to change an already built glider, it is generally easier to crack the fuse and glue in more tilt for big changes, for small changes twist the fuse and breath on it (hot, moist air to help set the twist). Leave the horizontal stab itself alone.

Bending the horizontal stab to add tilt doesn't do so well due to preferred grain orientation (from tip to tip perpendicular to the fuse when viewed from the top).

Bending the horizontal stab to add or remove elevator (change the incidence slightly as discussed earlier to improve the rollout at the top of the launch) is done frequently as the grain runs the right way to allow that.

Jeff Anderson
Livonia, MI

Are you guys placing the rudder and the stab ontop of the fuselage or how are you guys doing it?