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Alms for the aerodynamically unfit

Old 10-14-2009, 02:40 AM
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hillbillynamedpossum
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Default Alms for the aerodynamically unfit

Im well under way on my canard. I even named it....KACZKA (Its a polish word...look it up)

any way Im usuing this c/g finder http://adamone.rchomepage.com/cg_canard.htm
with these values:
Canard Root Chord (A): 9
Canard Tip Chord (B): 7
Canard Sweep Distance (S): 2
Canard Half Span (Y): 9
Wing Root Chord (AA): 16
Wing Tip Chord (BB): 11
Wing Sweep Distance (SS): 5
Wing Half Span (YY): 21
Distance between both LE's (D): 19.75
Enter Static Margin, then 10
Mean Aerodynamic Chord MAC = 13.65
Sweep Distance at MAC (C) = 2.35
From Root Chord to MAC (d) = 9.85
From Canard Root LE to AC = 25.51
From Canard Root LE to NP = 20.08
From Canard Root LE to CG = 18.71
Wing Area = 567
Canard Area = 144
Wing Aspect Ratio = 3.11
Foreplane Volume Ratio, Vbar = .042



The next step is finding wing load. Do I add the wing and the canard area togather for the purpose of wing loading, or just use the main wing value?

Also what is "Wing Aspect Ratio " and "Foreplane Volume Ratio, Vbar "


Thanks so much,

Possum

Last edited by hillbillynamedpossum; 10-14-2009 at 02:47 AM. Reason: copy and paste didnt work right
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Old 10-14-2009, 06:44 AM
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JetPlaneFlyer
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Wing aspect ratio is a measure of the 'slenderness' of the wing i.e. how long it is compared to it's width. Its calculated by dividing the span by the average chord (or span squared divided by wing area)

Vbar is a measure of the effectiveness of the tail (or foreplane). It's calculated by dividing the tail area by the wing area and multiplying by the product of tail moment arm divided by wing chord.

On a canard both wing and forplane provide lift so if you want to calculate stall speed then you should take the area of both surfaces into consideration.

Steve
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Old 10-14-2009, 11:56 PM
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hillbillynamedpossum
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THANKS for that Steve.
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Old 10-19-2009, 01:16 AM
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dbcisco
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Do you have to duck often when flying it?
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Old 10-19-2009, 04:31 AM
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hillbillynamedpossum
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Well the Polish duck is no more. I flew it into the dirt a few times, and on the last flight it broke in the air just where my wife said it would. ("Honey dont you think its a little thin right here?) GRRRRRRRRRR.

Oh well I recycled the main wing and hot glued it to a piece of 3/4" sch 20 pvc pipe and made up some new tail feathers and wow-wee-kaz-zow-wee Ive got a new stick plane. Not exactly slow but a pretty good save none the less.

I took it out and flew it a few laps, over controlled it, put it into a death spiral and crashed it (didnt have my wife there to tell me not to be stupid). It broke in three very pretty pieces that are already glued back togather.

Possum
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