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Dihedral effects on CL models

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Target:
The theory is that it flys a little faster than the inboard, and as such, would produce more lift and cause the model to "roll in" towards the center.
I reality, it seems that there are a lot of variables involved.
Building a symmetrical wing and just slightly offsetting the fuselage to the outboard a very small amount works. And it offsets the weight to the outside, so less tip weight needed, in theory.

I had to have the MonoKote joke explained to me as well. I guess some guy approached Larry and his plane had such a perfect finish that an RC(?) pilot observer asked what color of MonoKote it was, or something to that effect. Apparently, it was in front of a group of his peers, and the ribbing started from that point onward. (I think).

I had a SIMILAR experience...… I was shot point blank accidentally on a sportfishing boat. Got a "free helicopter ride" by the USCG to the nearest hospital. The bullet went through my kidney, colon, and liver, and into a passengers' lung that was standing on the stern of the boat. He went with us in the Helo, as well.
The charter Master came to the hospital to visit his buddy that took the bullet to the lung. He came to check on me. He said to me in the room, in front of the crew visiting me, "Chris, I sure am sorry about what happened. I was just down the hall visiting Dave, and he still has the bullet in the edge of his lung, they are afraid to take it out. You really didn't slow it down much, it went through you like you were a paper TARGET!"

Ever since, I have been known as "target"...…

I think Larry is lucky. Me, not so much! LOL.

R,
Target

Brett Buck:

--- Quote from: IdRatherBeBuilding on February 11, 2019, 11:50:23 AM ---Is this the reason the out board wing is a tad bit shorter on some designs?\

--- End quote ---

  No. That's a different effect (although it plays into it). The outboard wing goes a little faster than in the inboard, so if you have equal span wings, the lift is centered a little to the outboard side. If you want it in the center, then you need to make the inboard wing have a little more lift and drag than the outboard, so you make it a bit longer.

  It's not a huge effect. Say it's 70 feet from the center of rotation (where you pivot) to the center of the airplane, and the airplane is nominally going at 5.4 second laps. The fuselage goes about 440 feet in 5.4 seconds, or about 81.4 feet per second (55.5 miles/hour). If the span is 5 feet, the inboard tip goes about 78.5 feet/second, and the outboard about 84.4 feet/second. The outboard is about 7% faster, which (ignoring the other factors) would be expected to give about 15% more lift and drag. Of course the tips are the extremes of the example, and the overall effect is less.

    Without doing a lot of work, whenever I look at it,  for a 5 foot span airplane, you want something like 3/4" shorter outboard wing than inboard, more or less. You can make it work about as well with anywhere from 0 (equal) to maybe 1.5", but you'll definitely be able to tell the difference. Equal span will generally require *much more* tip weight, since you need to shift the center of gravity about 1/2" to the right to line up the CG and CP. Too much and you might end up putting weight on the inboard to shift it left.

     Brett

Howard Rush:

--- Quote from: Dan McEntee on February 10, 2019, 12:01:20 AM --- In short, the main purpose of dihedral in a control line model is to better locate the lead out exit in relation to the vertical CG of the airplane.

--- End quote ---

http://www.clstunt.com/htdocs/dc/dcboard.php?az=show_topic&forum=103&topic_id=287401&mesg_id=287401&listing_type=search#287879 
See post #7.

Air Ministry .:
Think it depends if the aerodynamic side loads exceed the gravitational / g force . Thus perpendicular leadouts get perpendicular aeroplanes .

Hurricane had Diheadral , assymetric  centersection aft of spar ,
and as somebody didnt trim the T E fore & aft to mate the straight plan line , it forced 2 mm washout on the 57 span FSR 40 / G 51 , version .
Current 67 in is unchanged anywhere , as V smooth in coastal winds , and a tight Sq Cnr .
A octave or two more responsive , or more tippy toey - Inverted .
Presumably the Wash IN inverted has the LIFT at  the earth side and other things over - is my perception of that idiosycrousey .However its spelked .
Other is marvelous though under the top loop in the V - 8 , alowing you to ' Hit ' the Control shift to the lower inside seemingly with all the time in the world .

A Martin Baker MB 3 , done with Al Rabes Formular and Airfoils , 20 Oz Sq Ft loading , seemingly flew itself ' on the line ' through the pattern .
It didnt have the Anti Yaw rudder , which in This Case in hindsight was careless . Regularly flow in good sailing weather , Never hit the deck .
Ordinarilly the full schedule , all but a few flights opening the wing joint with repeat Squares in a stiff breeze .
Frightening into the loop of the V 8 from inverted at 45 Deg  . But this plane seemed to have a autopilot . Smooth and no bounce
with consistant bottoms .
Tho a 440 dodge on a skid pan with a stuck throttle might be as relaxing. Generally 5.0 per lap , down to 4.8 in 20 knot air ,
like anyone else . Only ever one picture , still got the plan . Never shoulda given the wings away . Like the Mewgull empenage .

Wich was kindova Sweeper Or Adaminsin  like devise , with abit of Beringer thrown in . That Also was good , smooth , stable in wind .
Bar a 2 foot tip osscilation through the ' Wind Shear ' 60 ft up crosswind , on the coast . Blowing like stink .

A Spitfire , Aerodynamically pretty much a pirate of compostella's 4 stroke thing , when later ' diheadralled ' as it was built to be
convertable to , saw it go to livelier with the diheadral . Bit like going from a round to a Trigonic Tyre . As in lighter control response.
No other changes whatsoever other than leadouts refed parrallel again . Or is that tangental ? , Flat Anyway , Er Perpendicular , even .

A Eliptical Spitfire & another 65 span Mewgull ( which is aerodynamically unrelated to the small flap B I G  72 in one one . )

Then theres the P-38 .

 My observation is the presumably inward flow with fuse as catchfence , gets good outsides & ground effect ,
where if your not carefull , or out of trim , Mush on insides , as the airs forced outward, at entry & exit .
Youll notice this if the speeds off , outside its comfortable area . GENERALLY its not a bother .
Wether one automatically compensates I couldnt say , but you do deliberately when / if its ' off song ' , propellor wise , motorvationally that is .

Air Ministry .:
A few pitchers .

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