RC Gliders, Sailplanes and Slope Soaring Discuss rc gliders,rc sailplanes and slope soaring in this forum. Thermaling techniques, airfoils, tips, etc

Spoilerons

Reply

Old 03-29-2015, 04:20 PM
  #1  
JMCHASE
Senior Member
Thread Starter
 
Join Date: Jul 2014
Posts: 208
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default Spoilerons

What values woul you suggest for a three posiion switch and elevator?
JMCHASE is offline  
Reply With Quote
Old 03-29-2015, 07:28 PM
  #2  
aeajr
My Feedback: (2)
 
aeajr's Avatar
 
Join Date: Jan 2003
Location: Long Island, NY
Posts: 8,567
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

0, 50%, 100%

Elevator will have to be tuned to the particular plane but good starting points might be:

0, 15%, 25% up although on some planes, when you raise the ailerons as spoilerons you have to put in down elevator.
aeajr is offline  
Reply With Quote
Old 03-30-2015, 04:32 AM
  #3  
JMCHASE
Senior Member
Thread Starter
 
Join Date: Jul 2014
Posts: 208
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

What % up on a 3 pos switch for the spoilerons woul you suggest to start?
JMCHASE is offline  
Reply With Quote
Old 03-30-2015, 04:41 AM
  #4  
aeajr
My Feedback: (2)
 
aeajr's Avatar
 
Join Date: Jan 2003
Location: Long Island, NY
Posts: 8,567
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

75% of up aileron throw at 100% spoileron.
aeajr is offline  
Reply With Quote
Old 03-30-2015, 05:01 AM
  #5  
JMCHASE
Senior Member
Thread Starter
 
Join Date: Jul 2014
Posts: 208
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Not sure what 75 up at 100% aileron throw means?
JMCHASE is offline  
Reply With Quote
Old 03-30-2015, 05:07 AM
  #6  
aeajr
My Feedback: (2)
 
aeajr's Avatar
 
Join Date: Jan 2003
Location: Long Island, NY
Posts: 8,567
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Let's say you have your end point up aileron travel limit set at 20 mm. 75% of that would be 15mm. So, when you hit the switch for full spoileron deployment, 100% spoileron, the aileron should move up 15 mm.

Do your testing of these settings at 100 feet or higher in case you get strange behavior. I have seen people set up flaps, flaperons, spoilers and spoilerons then test them near the ground and wreck their plane.

You test high till you get the behavior you want. THEN you test near the ground.

This is especially true as you dial in your elevator comp setting for each spoileron setting. The only glider I have ever used spoilerons on was my Easy Glider and that needed down compensation, not up.

With full spoilerons deployed you want the glider to maintain a level or slightly nose down attitude, not go into a dive or balloon up. Same with setting up flaps. The goal is to reduce the glide ratio, not do dive the glider or stall it.



You might find this helpful:

GLIDE PATH CONTROLS

by Ed Anderson



Both power
planes and gliders can incorporate glide path controls to add to the options a
pilot has when flying his plane. We have all seen commercial airliners dropping
flaps during landings. Likewise gliders, which are flown without the use of a
motor, also benefit from glide path controls though they may be used in slightly
different ways on a glider in order to gain the best control during flight and
during landing. While a power plane has the option to “go around” if the
approach is not good, when a glider comes in to land, it is going to land.
Without a motor there is no going around. And gliders are often flown in
thermals where the lift can become so strong we may feel we need help to get
them out of the lift. That is why we may choose to incorporate glide path
controls into our aircraft.



For the rest of
the discussion I will focus on the controls and their use in the context of
gliders as this takes the effect and option of raising or lowering power out of
the discussion and focuses on the controls themselves. Even on gliders, these
glide path controls are not absolutely necessary as many glider pilots fly
without the use of glide path controls, but they can be helpful. Hopefully this
will clarify the terms and the use of these controls.


First, lets make sure we are using the same terms.

Spoilers and Spoilerons

Spoilers sit on top of the wing, typically near the spar. This is how the
Mystique RES is designed, for example.

Spoilers will reduce lift while inducing drag, but their primary value is
not as brakes but as lift reducers. This raises the stall speed, the speed at
which the wing can no longer produce enough lift to support the aircraft. So
the wing will stall at a higher speed. Some rise like barn doors. This is what
we typically call spoilers. Some come straight up like a blade. These we often
call air brakes.

When spoilers are deployed typically the nose will drop, due to reduced
lift, and we compensate with some up elevator to keep the glider from going into
a dive. The best effect is that the glider remains fairly flat but the sink
rate is raised so it comes down more quickly but without gaining a lot of
speed.

Spoilerons are trailing edge devices that go up. This might be based on
ailerons, full span ailerons, flaps or flaps and ailerons in combination.
Spoilerons will reduce camber, reducing lift. Think of this as raising the
trailing edge like an aileron but on both sides at once.
The wind hits the raised trailing edge and induces a pressure down at the
trailing edge of the wing. Whether you think of it as induced down force or
reduction of lift the effect is the same. When done on both wings at the same
time this often induces a rise in angle of attack, it picks up the nose since
the down force is behind the CG. This may require some down elevator
compensation to keep the glider from stalling.

Spoilerons induce drag as you raise them but their primary purpose is not
as brakes. This also raises stall speed meaning the wing will stall at a higher
speed. So spoilers and spoilerons are different but their overall purpose for
use is he same. The elevator compensation needed may be opposite.

Flaps and Flapperons

Flaps go down and increase the wing’s camber, makes the wing bottom more
concave. This causes more drag and more lift while reducing stall speed
allowing the plane to fly more slowly without stalling. That is why they help
fast planes land more slowly. What we are looking for is not the breaking
effect of the drag as much as it is the lowering of the stall speed which allows
the plane to land more slowly. When flaps are deployed the increased lift will
typically bring the nose up so we compensate with down elevator to avoid
stalling.

Flaps might be set to as much as 90 degree down angle. However 60 degrees
is typically all you need for enhanced, slower landing speed.
If you have a glider with ailerons you can use them as flapperons. This
works best when the ailerons are full span, like many discus launched gliders.
Here you get full trailing edge control with only one control surface on each
wing. You get thermal camber (trailing edge slightly down) and reflex
(trailing edge slightly up) and you get flap behavior and spoileron (not
spoiler) behavior if you can get enough upward motion. This works best on a
straight wing where any dihedral is at the root rather than a curved wing or a
polyhedral wing where dihedral is introduce gradually over the length of the
wing.

Brakes

All of these controls induce increased drag at sufficiently high angles of
deflection, so they can be used as brakes to either slow the aircraft down or to
prevent it from gaining speed. For example, imagine you are flying in a thermal
duration contest. You are in a thermal, are quite high and want to get down
fast so you can land at the exact time that will get you the best score. You
can extend your flaps or spoilers and push the nose over to go into a dive to
lose altitude quickly. Both will add drag which will reduce the amount of
speed you will gain in the dive. In my experience with RC gliders this works
better with flaps as flaps are usually larger than spoilers but it works for
spoiler too.

Likewise you can use these controls as you come near to whatever you
intended landing spot may be to dump energy and cut the glide short. Going to
90 degree flaps or 90 degree spoilers will induce drag to dump energy, but
again, because flaps tend to be larger they do a better job of this.

Spoilers do add the ability to “pin” the plane to the ground on landing.
Because they reduce lift, if you deploy spoilers on landing the wing will have
reduce lift and therefore the plane will have less of a tendency to rise off the
ground or hop as you land near the stall speed of the airplane or glider,
especially in gusty landing conditions. The next time you ride that big
airliner watch the wings on landing. Once they touch, many will raise spoilers
or airbrakes to help slow the plane and reduce the lift of the wing so the plane
has less chance of going back into the air.

Versatility

In my opinion, flaps are more versatile than spoilers as you can use them
to lower stall speed or increase it. However flaps are also more
dangerous.

If you lower flaps, reducing the stall speed you can slow the plane down
and keep flying below the normal stall speed. If you pull the flaps in because
you realize you are not going to make the field you MAY stall because as you
pull the flaps in the stall speed goes back up. If you are flying too slowly
the plane will drop like a rock.

Spoilers on the other hand are more forgiving. If you apply spoilers too
soon and realize you want to extend the glide you can retract the spoilers which
lowers the stall speed. You will not stall and you will not drop out of the sky.
The glide is extended. Personally I prefer spoilers for new pilots for this
reason. Gliders with R/E and spoilers are called RES gliders.

Each approach has advantages. Flaps more versatile but more prone to error.
Spoilers are less versatile but more forgiving of errors.
If I was modifying the trailing edge, I would make them flaps rather than
spoilerons. However if I was a new glider pilot and wanted to avoid those
stalling errors, I would install spoilers, not spoilerons.

I learned to fly gliders on a RES glider, a Great Planes Spirit. I fly RE,
RES, REA and full house REAF gliders and I enjoy them all. But you fly them all
a little differently. The more controls, the more versatile and the greater
propensity for mistakes.
Of course, your smileage will vary.

Last edited by aeajr; 03-30-2015 at 05:28 AM.
aeajr is offline  
Reply With Quote
Old 03-30-2015, 05:17 AM
  #7  
JMCHASE
Senior Member
Thread Starter
 
Join Date: Jul 2014
Posts: 208
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

What woul be the average up aileron for say a two meter wingspan. Not ysure if that is a legit question considering all the perameters but on most airplanes the servo travel can be extensive. That raises another question...is there a formula for control surface travel taking in all other aspects of the airplane...weight wingspan. Etc ?
JMCHASE is offline  
Reply With Quote
Old 03-30-2015, 05:23 AM
  #8  
JMCHASE
Senior Member
Thread Starter
 
Join Date: Jul 2014
Posts: 208
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Also, about how much elevator travel do you suggest and up or down?
JMCHASE is offline  
Reply With Quote
Old 03-30-2015, 05:45 AM
  #9  
JMCHASE
Senior Member
Thread Starter
 
Join Date: Jul 2014
Posts: 208
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Thanks. This Ed Anderson sounds very knowledgeble who is he does he affilate with another club or have a web site? Sounds like he may have other words of wisdom on RC...
JMCHASE is offline  
Reply With Quote
Old 03-30-2015, 05:52 AM
  #10  
JMCHASE
Senior Member
Thread Starter
 
Join Date: Jul 2014
Posts: 208
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Dumb me i just read the article and noticed the signature and affiliation
JMCHASE is offline  
Reply With Quote
Old 03-30-2015, 06:05 AM
  #11  
aeajr
My Feedback: (2)
 
aeajr's Avatar
 
Join Date: Jan 2003
Location: Long Island, NY
Posts: 8,567
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

To your questions, set your surfaces according to the instructions for the plane. When all else fails, read the instructions.

Here are a few of my other articles.

EVERYTHING
YOU WANTED TO KNOW ABOUT ELECTRIC POWERED FLIGHT
http://www.rcuniverse.com/forum/m_7100376/tm.htm

SIX KEYS TO SUCCESS FOR NEW PILOTS
Six Keys to Success for new pilots


TRYING
TO PICK YOUR FIRST PLANE?
http://www.rcuniverse.com/forum/m_11396769/tm.htm

THINGS
TO CHECK ON AN ARF
http://www.wattflyer.com/forums/showthread.php?t=70022


>
THINGS TO CHECK ON AN RTF
> http://www.rcuniverse.com/forum/m_6582895/tm.htm
>


HOW
TO FIX WARPS, DENTS, TWISTS OR UNCRUNCH FOAM PARTS
http://www.wattflyer.com/forums/showthread.php?t=66805
aeajr is offline  
Reply With Quote
Old 03-30-2015, 06:16 AM
  #12  
JMCHASE
Senior Member
Thread Starter
 
Join Date: Jul 2014
Posts: 208
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Forgive me im just waking up i should have checked who i was talking too....
JMCHASE is offline  
Reply With Quote
Old 03-30-2015, 06:25 AM
  #13  
aeajr
My Feedback: (2)
 
aeajr's Avatar
 
Join Date: Jan 2003
Location: Long Island, NY
Posts: 8,567
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

You asked.
aeajr is offline  
Reply With Quote
Old 04-01-2015, 08:06 AM
  #14  
JMCHASE
Senior Member
Thread Starter
 
Join Date: Jul 2014
Posts: 208
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

I was looking at the Radian Pro wanted your opinion? Thanks
JMCHASE is offline  
Reply With Quote
Old 04-01-2015, 04:56 PM
  #15  
aeajr
My Feedback: (2)
 
aeajr's Avatar
 
Join Date: Jan 2003
Location: Long Island, NY
Posts: 8,567
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

For what purpose? Thermal? Slope? Aerobatics? Hotliner? Competition?


Good e-glider. Flies well. You seem them at ALES contests from time to time.

For thermal soaring I like the original Radian better.

Pro thermals fine and is better for windy conditions and for slope.

Neither is hotliner. Pro is more aerobatics but still, not very.

Last edited by aeajr; 04-01-2015 at 05:19 PM.
aeajr is offline  
Reply With Quote
Old 04-01-2015, 06:04 PM
  #16  
JMCHASE
Senior Member
Thread Starter
 
Join Date: Jul 2014
Posts: 208
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

My first sailplane was the Aquila I built in 1985 since then i flew power and the was introduced to electric sail. I stoped flying when the family started growing other needs then came back recently. Thing is i like powered sail i dont have the interest i did in free flight at least not now maybe later so im looking for a decent powered sailplane thats why i asked about the Radian pro. In 2 m range there abouts
JMCHASE is offline  
Reply With Quote
Old 04-02-2015, 01:26 PM
  #17  
aeajr
My Feedback: (2)
 
aeajr's Avatar
 
Join Date: Jan 2003
Location: Long Island, NY
Posts: 8,567
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Good to know but does not answer my question.

You may not realize but there are many types of gliders and many types of glider flying. Just as power planes have scale and pattern and 3D and ..... so sailplanes/gliders have their sub categories. I listed several. Before I can render an opinion I need to understand what kind of flying you intend to do.

Radian Pro is a pretty good all around Receiver ready or bind and fly glider. It won't match the high end molded planes and it certainly doesn't qualify as a hot liner. Does OK on the slope. Fun for sport flying but would not be considered a top choice for contest flying in ALES or F5J competition.
aeajr is offline  
Reply With Quote
Old 04-02-2015, 02:15 PM
  #18  
JMCHASE
Senior Member
Thread Starter
 
Join Date: Jul 2014
Posts: 208
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Sorry i was not clear. I was disabled several yrs ago been in rehab now getting back on my feet. I love sailplanes was watching them back in 1958 on the cliffs overlooking pacific ocean. Right now im fighting pain vs walking most i can do today is build and spend an hour at the park before i have to stop. I was looking for something that was a fairly decent powered glider i could throw together or build and fly for an hour. I just finished converting an older model from speed brushed to brushless its in the rebuild thread Looking for full house in that area.
JMCHASE is offline  
Reply With Quote
Old 04-02-2015, 03:02 PM
  #19  
aeajr
My Feedback: (2)
 
aeajr's Avatar
 
Join Date: Jan 2003
Location: Long Island, NY
Posts: 8,567
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Radian Pro should be a good choice.
aeajr is offline  
Reply With Quote
Old 04-02-2015, 03:15 PM
  #20  
JMCHASE
Senior Member
Thread Starter
 
Join Date: Jul 2014
Posts: 208
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

I like what im reading on the e-flite Mystique 2.9 Just curious how much room there is in the bay for telemetry and such. I think from what im reading the pro is a little too finished
JMCHASE is offline  
Reply With Quote
Old 04-02-2015, 07:37 PM
  #21  
aeajr
My Feedback: (2)
 
aeajr's Avatar
 
Join Date: Jan 2003
Location: Long Island, NY
Posts: 8,567
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Too finished? What does that mean?

Mystique is a very popular lower end glider.
aeajr is offline  
Reply With Quote
Old 04-02-2015, 08:13 PM
  #22  
JMCHASE
Senior Member
Thread Starter
 
Join Date: Jul 2014
Posts: 208
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

I like to build when i have time even if just adding things like motors servos telemetry the radian does not need anything except to charge a battery align a few things and fly. Sorry about the confusion.
JMCHASE is offline  
Reply With Quote
Old 04-03-2015, 06:17 AM
  #23  
aeajr
My Feedback: (2)
 
aeajr's Avatar
 
Join Date: Jan 2003
Location: Long Island, NY
Posts: 8,567
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

No problem. Just wanted to understand your post.

Don't know what is in your price range but here are some "low cost" ships for you to consider.

RM Mandarin 2 ARF 3.7m - might be too large for your needs
http://www.hobbyclub.com/product_inf...oducts_id=1595

Avia - two in my club - pilots lke them
http://www.espritmodel.com/avia-2-5e...s-arc-arf.aspx

Prelude - 2.5M - good reports
http://www.espritmodel.com/prelude-2...s-arc-arf.aspx
aeajr is offline  
Reply With Quote

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off


Thread Tools
Search this Thread

Contact Us Archive Advertising Cookie Policy Privacy Statement Terms of Service