Wing Loading and Cubic Wing Loading
#1
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From: Round Rock,
TX
What is an acceptable wing loading for flying good 3D on a 27-28% plane?
Is a wing loading of 30.45 oz/in or a cubic loading of 9.76 oz/cu. ft. ok?
Is a wing loading of 30.45 oz/in or a cubic loading of 9.76 oz/cu. ft. ok?
#3
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From: Round Rock,
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Can't be...[X(]
Using this site here...http://adamone.rchomepage.com/design.htm
A EF YAK with a DA50 at around 1400sq and 15.5lbs...is 25.51oz/sq ft. and is that about one of the absolute best case scenarios...yet its already slightly past your highest range.
Using this site here...http://adamone.rchomepage.com/design.htm
A EF YAK with a DA50 at around 1400sq and 15.5lbs...is 25.51oz/sq ft. and is that about one of the absolute best case scenarios...yet its already slightly past your highest range.
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From: Round Rock,
TX
ORIGINAL: Silversurfer
Your plane would fly well at 34 oz/sq. ft. depending on available power. More power makes 3D possible.
Your plane would fly well at 34 oz/sq. ft. depending on available power. More power makes 3D possible.
#6
for really good 3D that size is better at 25 -- My own EF YAK weighed 15.25 with piped ZDZ50 -turning Mejzlic 22x8 at 7750 static
instant acceleration and super slow falling maneuvers
lots o power and min weight is the 3D formula- no way around it
but -- my 39 lb pig of a 42% at 2600 squares -is 34 lb loading and is also a "feather " relatively. just not the acceleration of the YAK
My EDGE at 23 lbs and 1650- is close to 33+-- not as good at slow 3D but still very good at power maneuvers. Lots o power.
30 - is a decent number for most stuf -in THAT size ---- but lower is better -
now go to really good electric flat foamies - the power to weight is far far better and the performance is like a hummingbird
wing loadings of 3-4 ounces per sq ft.
instant acceleration and super slow falling maneuvers
lots o power and min weight is the 3D formula- no way around it
but -- my 39 lb pig of a 42% at 2600 squares -is 34 lb loading and is also a "feather " relatively. just not the acceleration of the YAK
My EDGE at 23 lbs and 1650- is close to 33+-- not as good at slow 3D but still very good at power maneuvers. Lots o power.
30 - is a decent number for most stuf -in THAT size ---- but lower is better -
now go to really good electric flat foamies - the power to weight is far far better and the performance is like a hummingbird
wing loadings of 3-4 ounces per sq ft.
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From: Gatineau,
QC, CANADA
Don't forget that there is a scale effect, the more wing area "over all" the higher that number can go I think.
Like on a 28% I would go no higher than 30 oz/in. ( depending on your location, altitude, air temp) for good 3d.
On a 35% you can go to about 32 oz/in and have the same result as the 28% on 30 oz/in.
On a 40% you can go to about 34 oz/in and it will fly like a 28% at 30 oz/in.
Or so it seems to me.
Also altitude were you fly, and temperature, will have an effect on lift.
Cooler air = more lift
Denser air = more lift
Like on a 28% I would go no higher than 30 oz/in. ( depending on your location, altitude, air temp) for good 3d.
On a 35% you can go to about 32 oz/in and have the same result as the 28% on 30 oz/in.
On a 40% you can go to about 34 oz/in and it will fly like a 28% at 30 oz/in.
Or so it seems to me.
Also altitude were you fly, and temperature, will have an effect on lift.
Cooler air = more lift
Denser air = more lift
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From: Ithaca, NY
Hi,
If you want to "design" planes of different sizes to fly similar, you need to use the cubic loading formula for comparison. Simple oz/sq ft calculations are not represensitive. thus the saying "larger planes fly better" For example, a 25% cap with a wing loading of 25 oz/sq ft will fly the same as a 33% cap with 32 oz/sq ft, etc. (these are just figures to illustrate the concept, not actual calculations)
Elson
If you want to "design" planes of different sizes to fly similar, you need to use the cubic loading formula for comparison. Simple oz/sq ft calculations are not represensitive. thus the saying "larger planes fly better" For example, a 25% cap with a wing loading of 25 oz/sq ft will fly the same as a 33% cap with 32 oz/sq ft, etc. (these are just figures to illustrate the concept, not actual calculations)
Elson
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From: Gatineau,
QC, CANADA
I agree, its what I was saying. Without having to get into all the formulas it was just worth noting that.
By the way what is the formula.
Thanks.
By the way what is the formula.
Thanks.
#11
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From: Round Rock,
TX
Yes, cubic loading is suppose to be something you can compare across plane sizes. For example, a EF Yak87 at 5.5lbs would be a cubic loading of 8.18. I'm suggesting a cubic loading between 9.24 (best case) and 9.76 (worst case).
[link=http://adamone.rchomepage.com/design.htm]Heres the formula.[/link]
[link=http://adamone.rchomepage.com/design.htm]Heres the formula.[/link]
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From: Gatineau,
QC, CANADA
I used the cubic loading program to see what I get with my 3D planes.
1/4 Extra is 28.8 oz/sq ft wing loading.
Cubic loading for that one is 10.33.
In the real world it flies light, good 3D!
35% Ultimate is also 28.8% wing loading.
Cubic loading for that one is 7.58.
In the real world it flies very light too, good 3D. I find it just a little better than the little extra, but then its a bipe, two wings seem to get less lift that one big one over all.
35% Extra with a whopping 34.21 oz/sq ft wing loading.
Cubic loading for that is 9.81! Hmmm, less than the little Extra, even with a much higher wing loading.
In the real world it flies as light as the little extra, soooo I can verify from my experience that its all rather accurate.
1/4 Extra is 28.8 oz/sq ft wing loading.
Cubic loading for that one is 10.33.
In the real world it flies light, good 3D!
35% Ultimate is also 28.8% wing loading.
Cubic loading for that one is 7.58.
In the real world it flies very light too, good 3D. I find it just a little better than the little extra, but then its a bipe, two wings seem to get less lift that one big one over all.
35% Extra with a whopping 34.21 oz/sq ft wing loading.
Cubic loading for that is 9.81! Hmmm, less than the little Extra, even with a much higher wing loading.
In the real world it flies as light as the little extra, soooo I can verify from my experience that its all rather accurate.
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From: Round Rock,
TX
Ok great...yes...hard to tell if those numbers mean anything in the real world...and you have 2 out of 3 that are above the cubic wing loading I suggest so perhaps its doable then.
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From: Gatineau,
QC, CANADA
Looks to me like anything with a 10 Cubic wing loading, or close to it will 3D.
And I know how to 3D, I am talking slow 3D, rolling harriers, harriers, high alfa knife edge, avalanches, flat spins, all that cool stuff
And I know how to 3D, I am talking slow 3D, rolling harriers, harriers, high alfa knife edge, avalanches, flat spins, all that cool stuff



