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Old Yesterday, 11:16 AM
Will fly for food
davidjensen's Avatar
Bellevue WA,
Joined Dec 2003
6,903 Posts
Nice I'll bet it improves visibility as well. I do wonder about the bottom being curved such that the end of the rudder will be in direct contact with the ground. It may limit its longevity.
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Last edited by davidjensen; Yesterday at 01:02 PM.
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Old Yesterday, 12:14 PM
Team JR
Doug Cronkhite's Avatar
San Diego
Joined Feb 2002
1,640 Posts
Finch's primary Snipe uses a Swindell horizontal, and a Siler vertical.
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Old Yesterday, 05:33 PM
One Idiot is plenty...
Dbox's Avatar
Planet Earth
Joined Jun 2005
5,167 Posts
Quote:
Originally Posted by davidjensen View Post
It may limit its longevity.
Good for the whole season.
Yuri
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Old Yesterday, 05:48 PM
Win=span\massXpractice+lu ck
webbsolution's Avatar
Joined Jul 2007
2,995 Posts
Lefty conversion

Joe,

Can a left handed rudder be flipped over for a right handed fuse ?
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Old Yesterday, 06:11 PM
Hugh Blackburn
floquet's Avatar
Melbourne, Australia
Joined Jun 2005
478 Posts
Quote:
Originally Posted by kcaldwel View Post
It depends a lot on the airplane configuration whether the tail lifts up or down, and at what speeds. That has nothing to do with the aircraft stability.

The down wash angle from the wing means the required stab or elevator angle for trim at any wing Cl is not obvious from inspection.

The drag from any small elevator deflections is infinitesimal, and really doesn't need to be worried about. Having some small deflection at neutral can reduce hysteresis in the elevator control, making the airplane respond more linearly to pitch commands.

The stab operates at low Re (generally high drag to generate lift), and is usually lower aspect ratio than the wing. That means it should cause more drag to generate any lift than using the wing to generate it all. Since the stab is in the downwash from the wing, any lift it generates also has a rearward component that acts as drag.

Every analysis I have ever seen shows minimum drag and best L/D of a tail aft airplane configuration with a slight down load on the tail.

Minimum sink rate is highly dependent on the max Cl of the wing (Cl^3/2/Cd). I have never seen an analysis where the minimum sink is better with an aft stab lifting, but perhaps it is possible when combined with some low Re effects?

Kevin
Moving the CG back as far as one feels comfortable with (a) reduces wing loading by removing nose weight and (b) up to a point, at least, reduces the tail load - up or down. Both are good for reducing sink rate (provided one doesn't need significant control inputs to fly). I guess the interesting point was that the tail load could change from down to up with reducing airspeed at the same CG.

I only use 71mm for dead calm and for my heavy Snipe (250gm). It seems easy enough to fly at that setting. For the lighter one (225gm) I don't like it there, and use 68mm instead (so perhaps there is a Re effect). In dead calm, of course I use the light plane anyway if I have it with me!

Hugh
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Old Yesterday, 06:23 PM
Do it AGAIN! This time BETTER!
ThermalThief's Avatar
WA
Joined Jan 2005
449 Posts
Hugh,

Can you tell me what camber setting you use on your models? Curious how the two compare.

Ken
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Old Yesterday, 11:40 PM
launch low, fly high
New Zealand, Hawke's Bay, Havelock North
Joined Dec 2004
1,837 Posts
Quote:
Originally Posted by webbsolution View Post
Joe,

Can a left handed rudder be flipped over for a right handed fuse ?

The fin/rudder is symmetric vertically, which means that they are not "handed". Left handed pilots install the hinge on the right, right handed pilots install the hinge on the left.
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Old Today, 04:10 AM
Hugh Blackburn
floquet's Avatar
Melbourne, Australia
Joined Jun 2005
478 Posts
Quote:
Originally Posted by ThermalThief View Post
Hugh,

Can you tell me what camber setting you use on your models? Curious how the two compare.

Ken
Hi Ken

I have to confess that my settings (and in fact these CG locations, along with their variations with weight) are a 100% straight theft from Joe's (so go back and check his posts on settings). Perhaps I believe what he says too well, or perhaps I'm just lazy! But either way, they seem pretty much right to me.

Hugh
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Old Today, 09:25 AM
Maurice
mpodder's Avatar
Bakersfield, Cal.
Joined Jul 2004
1,090 Posts
Quote:
Originally Posted by DrewV View Post
I start with my body oriented parallel (in-line) to the wind.
I always remember Jun saying
If you go back and look at Jun's instruction videos you will see, as you, he says to stand square to the wind for your start. Then, because he is a right handed thrower, he starts with the right foot and that first step is at almost a 90 deg. angle to the right. He then shows the purpose of that step. It winds the torso as a spring automatically and the quick release of that stored energy is what produces good launches. The release is almost the same motion as that huge drive off the tee or monstrous forehand that little 13 year old girl drives you off the court with

Just what I think
Maurice
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Old Today, 10:30 AM
Will fly for food
davidjensen's Avatar
Bellevue WA,
Joined Dec 2003
6,903 Posts
It also produces a somewhat spiral path inwards to the left which can increase the speed of the launch.
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Old Today, 11:31 AM
One Idiot is plenty...
Dbox's Avatar
Planet Earth
Joined Jun 2005
5,167 Posts
Penalty for more secure solid carbon bottom and touch of accent paint vertical was 0.5 gr

Yuri
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Old Today, 11:36 AM
hot air rises...
jfinch's Avatar
Pleasant Grove, UT
Joined Jul 2005
7,653 Posts
Nice Yuri! Did you say the vertical is thinner than the OEM? How well does it fit into the boom cutout?
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Old Today, 02:04 PM
One Idiot is plenty...
Dbox's Avatar
Planet Earth
Joined Jun 2005
5,167 Posts
Quote:
Originally Posted by jfinch View Post
Nice Yuri! Did you say the vertical is thinner than the OEM? How well does it fit into the boom cutout?
It is actually fits pretty good,not as tight as original.
I am using IC 2000 glue to fill small gaps.
Plane is 245gr at 62mm CG ( repaired boom)
Yuri
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Old Today, 02:06 PM
Registered User
United Kingdom, Hertfordshire
Joined Sep 2014
25 Posts
I have 4 D47s servos in my Snipe. I am thinking to replace the aileron servos to Hyperion DS09 AMD servos. As these servos are slightly bigger (And in front) and I rather not move Rudd/elev servos I need to lengthen the flapperon pushrods. Are these Snipe pushrods for sale? Any other options?
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Old Today, 02:31 PM
Will fly for food
davidjensen's Avatar
Bellevue WA,
Joined Dec 2003
6,903 Posts
I built my own out of carbon rods and .047" wire. They are unsupported and stiffer than the original setup. They are about 1g heavier. I wrap the ends with Kevlar tow and CA. The wires ends that go inside the carbon tube is dented with a wire cutter to put deformities into the wire so the glue has more to stick to.
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