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The makers of Prime Sport planes offer either a double taper 90" wing or an 82" straight wing. (constant cord)
Which would be better for sport aerobatics? (snaps, spins, and rolls) No 3-D.
Both have the same wing area. (around 1240sq. in.)
Also what is the advantage of a "flying tail"? (airfoil stab. and fin)
Power will be a Zenoah G45.
All-up weight should be around 16 pounds.
Thanx...croz

rmh

If you can tell the difference I will be surprised.
there will also be differences in thickness etc., so the trying to lay it all on the differences in planform (outline) is impossible
theory says the LE sweep adds stability- depending on the rest of theairplane - it may be noticable but past experience says -it all will add up close to the same

da Rock

The advantages of a stabilator? Not sure there are any that the flyer might notice.

It's usually a lighter structure.
It won't ever have leaking elevator gaps. (but can have a leakage problem at the fuselage)
It might have less drag.
Can't think of any others.

da Rock

Straight wing VS taper?

Dick covered it BUT..........

This summer I noticed that a couple of the straight winged planes I fly with others (buddy box) were pushed around in the roll axis in bumpy air. They were all the same design which seems to me to have longer span (and area) than needed. And I figured that design made them over react because that extra area, way out on the wing where it has extra leverage, was giving the bumpy air an easy job of jostling the airplane. My airplanes that have tapered wings didn't seem to get pushed around to the same degree. ........... and that's a seat of the pants observation and a WAG as to the reason.

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Good info...keep 'em coming..
I was leaning toward the taperd wing, and this re-enforces my notion.
Also, I think they look better.

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I always seal the gaps. Even in the gassers.
The sheeted foam would perhaps, be lighter than a sticks and planking tail?

Rotaryphile

A wing with 40% or more taper produces at least ten percent less induced drag, and three percent less profile drag than that of a constant chord wing of the same span and area. The tapered wing will also have much less aileron-induced yaw, and thus it will produce more axial rolls and nicer handling. The tapered wing also requires much less aileron torque input to produce a given roll rate.
The structural advantage of a tapered wing is also quite large, since the wing can accomodate much deeper spars near the root, where bending moments are maximum. I would be extremely surprised to see an unlimited aerobatic full-scale monoplane with a constant chord wing - most of them currently use around 50% taper, giving a tip chord of about half that of the root chord.

When constant chord wings are used in full-scale airplanes, it is usually simply to reduce construction costs, since most of the ribs can be nearly identical.

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I'm sold!
Many thanx...croz

rmh

Unless the area of the two remains constant -- your comparisons seemed to ignore that .
in this case the rectangular wing is shorter and efectively you get very similar responses , in fact the roll rate of the straight SHORTER span can be higher .
Sure the tapered wing looks great - but effectively , very low aspect ratio short span wings have a lot to offer -
for one thing -in this size model the RN is better .
In direct comparisons we made with quite small electric fully aerobatic models (foamies we made) -straight winged 3.3-1 aspect ratio wings gave up nothing compared against tapered wings
The Cassut is a fuly functional unlimited aerobat .
They just do have not the appeal .
In full scale stuff the advantage may go to the highly tapered layout -

Rotaryphile

My comparison is of tapered and constant chord wings of "equal span and area". Taper is not a panacea - it has its downside too, chiefly by being more prone to tip stall, although a tapered wing will produce smaller yawing moments up to the point where it stalls, simply because the area out near the tip is smaller, and thus develops less drag. At very low reynolds numbers, constant chord wings might well have superior aerodynamics, although they will tend to be heavier when compared to a tapered wing that is designed to resist the same aerodynamic loads.