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best brakes - crow or flaps only?

Old 03-05-2009, 09:36 AM
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Tim Green
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Default best brakes - crow or flaps only?

I'm setting up brakes on a 3m ship, and I've seen where some pilots brake with just flaps, and others brake with crow (flaps down, ailerons slightly up).

I'm hoping you can help me, to determine which is best for my application - which is sport landings on short runways - not contest landings.

What do you use? Crow, or flaps only? Which should I be using?
Old 03-05-2009, 10:51 AM
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evan-RCU
 
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Default RE: best brakes - crow or flaps only?

If you have a four servo wing crow is deffinitely better. The up ailerons cancel most of the pitch changes caused by the flap deployment while spoiling more of the wing lift.
Old 03-05-2009, 12:45 PM
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Tall Paul
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Default RE: best brakes - crow or flaps only?

The pitch change when flaps are retracted is nose-down.
Close to the ground that's not a "good" direction.
Crow makes more sense.
Or spoilers. The pitch change with these on retraction is nose-up.
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Old 03-05-2009, 03:25 PM
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Default RE: best brakes - crow or flaps only?

Like Evan said, if you have a 4 servo wing give crow a shot. My Spirit Elite will near about stop in mid air when you go full crow.
Old 03-05-2009, 06:58 PM
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iflytailies
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Default RE: best brakes - crow or flaps only?

I agree with what was said
Old 03-06-2009, 07:41 AM
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Tim Green
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Default RE: best brakes - crow or flaps only?

Looks like crow has some advantages over flaps only. Thanks for all of your help. [8D]
Old 03-06-2009, 08:01 AM
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evan-RCU
 
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Default RE: best brakes - crow or flaps only?

Of interest the "other" site says to try both for yourself and it looks like there are as many saying just flaps. Interesting the difference in response between sites.

For bakes though I think crow is much better.
Old 03-09-2009, 12:51 PM
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gopherhunter
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Default RE: best brakes - crow or flaps only?

I'm flying an electric Spirit Elite right now. Can you tell me what your flaps and aileron settings are for crowing? How far from neutral at full crowing? My transmitter only allows me full-on or full-off, each on a separate switch, so maybe that is a problem? Plane flies great, but landings are scary-she's fast. I'm fairly new at this, but I'm thinking that with the right starting point on those travels, she'll come in easier, and I can maybe engage crowing at a higher altitude and fly her to landing. Or will crowing make her stall? I can do flaps only or up ailerons only if that will help slow her down. This is my first glider with flaps/ailerons, so your help will be greatly appreciated. My landing area is short, hence the need for crowing.
Old 03-09-2009, 01:09 PM
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Default RE: best brakes - crow or flaps only?

What radio are you using?
Old 03-09-2009, 01:53 PM
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Default RE: best brakes - crow or flaps only?

JR XF631 with R700 receiver 7 channel
Old 03-09-2009, 02:19 PM
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Default RE: best brakes - crow or flaps only?

Can't do it with that radio, sorry.

http://www.jrradios.com/Products/Def...odID=JRP6219**
Old 03-11-2009, 07:56 PM
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Default RE: best brakes - crow or flaps only?

You can do it with that radio just fine. Use flaperons on channels 1 and 6, these will be the outboard normal ailerons. Use channel 5 for inboard flaps. Not sure on that radio if it is on a switch or on an adjustable dial, if on a dial then you can adjust flaps for flight conditions, like reflex for more speed or nuetral for normal flight, flaps down for landing and extra lift at launch. If on a 2 position switch then your limited to flaps up or down only. This way you can reflex entire trailing edge, use entire trailing edge for flaps, or for crow. You just need to switch flaps and flaperons seperately. Hope this helps!
Old 03-11-2009, 08:39 PM
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Default RE: best brakes - crow or flaps only?

Flaperons and flaps will not get you crow..........
Old 03-11-2009, 09:15 PM
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Default RE: best brakes - crow or flaps only?

Sure does, inboard section flaps down, outer aileron/flaperons up. Unless I'm missing the feathers that is the crow position. Unless there is something else to the crow position I'm missing that about does it, plus you still get to use ailerons to keep wings level. Pretty basic stuff.
Old 03-12-2009, 03:32 PM
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Default RE: best brakes - crow or flaps only?

I think the terminology is confusing. You're calling something flapperons that most of us just refer to as ailerons, even if you use spanwise camber.
Old 03-19-2009, 10:23 PM
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Tim Green
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Default RE: best brakes - crow or flaps only?

I'm happy now - I've programmed both crow and flaps only into my sailplanes.

I programmed in Butterfly (crow), but two different ways, depending on the condition I select on my Futaba 12FG. Thus I have, at the flick of a switch, full Butterfly, with ailerons, elevator and flaps. Or limited Butterfly, same as the full but without the ailerons.

I'm just starting to take advantage of the 12FG - and I also programmed in different aileron differential with the Butterfly on than I have with the Butterfly off. This solves the drag issue when turning while full Butterfly is deployed. And it lets me experiment with flaps only using the limited Butterfly. All without having to land and reprogram my radio.

The 12FG is one nice, flexible, radio. But it has a learning curve to it. I'm only just starting to get use to it.

And I can also play with camber now.
Old 04-13-2009, 12:38 AM
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dumorian
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Default RE: best brakes - crow or flaps only?

I have a 12FG and a 12Z. The way I like to set up butterfly/crow and flaperon/spoileron is on the side sliders. I set crow on the left slider as to me it is like the throttle on a powered glider. This gives me full control of crow from none to full. I also mix in elevator with crow so as to offset the up or down effect from applying crow. So far for me, this has been a tendency to nose up.

So, full up on the left slider if like full throttle or no crow... full down is like 0 throttle or full braking. I'm still amazed at watching a glider dive in, flair, dump off speed and land... Others watching are thinking this ain't gonna happen... but then it does.

Flaperon/Spoiler I put on the right slider. The center position is nuetral. Again, moving the slider up is to me like more throttle or speed, so this move the ailerons up. Pulling back is flaperon or aileron down... slow down to stay in an updraft longer.

Also, you should take a look at the full span aileron mode. This will move the ailerons and flaps together... if your flaps can go upward. This adds a lot of aerobatic authority. The radio can be programmed for equal movement or proportional. I normally run proportional all the time.

The good thing about this setup as a whole is it still works even in full crow mode (assuming you are not *****g out your travels), so you still have really good aileron authority during a full crow landing.

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