Whats with the aerodynamics on foan planes
10-19-2013, 06:48 AM
#1
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Whats with the aerodynamics on foan planes
Guys,
I was looking through some images from my local flying club web site and came accross an image of a foam plane which was essentially a 30mph speed sign (a disc) which flew.
The foam wings were just sheet foam cut to shape with no curved top or bottom to create the classic wing profile.
So how do these planes create lift if not with the wing?
I always assume hte elevator must be trimmed down to create lift or essentially create a slightly upward angle of attack for the entire plane.
Is that correct?
Foam is cheap so I fancy having a dabble to see what stupid stuff I can make. Maybe even an actual plane shape too!!
I was looking through some images from my local flying club web site and came accross an image of a foam plane which was essentially a 30mph speed sign (a disc) which flew.
The foam wings were just sheet foam cut to shape with no curved top or bottom to create the classic wing profile.
So how do these planes create lift if not with the wing?
I always assume hte elevator must be trimmed down to create lift or essentially create a slightly upward angle of attack for the entire plane.
Is that correct?
Foam is cheap so I fancy having a dabble to see what stupid stuff I can make. Maybe even an actual plane shape too!!
10-19-2013, 07:19 AM
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Guys,
I was looking through some images from my local flying club web site and came accross an image of a foam plane which was essentially a 30mph speed sign (a disc) which flew.
The foam wings were just sheet foam cut to shape with no curved top or bottom to create the classic wing profile.
So how do these planes create lift if not with the wing?
I always assume hte elevator must be trimmed down to create lift or essentially create a slightly upward angle of attack for the entire plane.
Is that correct?
Foam is cheap so I fancy having a dabble to see what stupid stuff I can make. Maybe even an actual plane shape too!!
I was looking through some images from my local flying club web site and came accross an image of a foam plane which was essentially a 30mph speed sign (a disc) which flew.
The foam wings were just sheet foam cut to shape with no curved top or bottom to create the classic wing profile.
So how do these planes create lift if not with the wing?
I always assume hte elevator must be trimmed down to create lift or essentially create a slightly upward angle of attack for the entire plane.
Is that correct?
Foam is cheap so I fancy having a dabble to see what stupid stuff I can make. Maybe even an actual plane shape too!!
Lift is a reaction force, a flat plate can deflect air downwards and this deflection has an equal and opposite reaction that is lift and drag.
A flat plate can generate lift, but an aerofoil shape does it far more efficiently.
These videos might help.
http://www.youtube.com/watch?v=zV06PgxarW0 http://www.youtube.com/watch?v=OyjQSEKZoA0 http://www.youtube.com/watch?v=aFO4PBolwFg
Last edited by Rob2160; 10-19-2013 at 07:31 AM.
10-19-2013, 04:13 PM
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These videos are great! I remember back in college (never mind how far back that was!) when my professor was reciting the same, tired explanation of lift being entirely the result of faster air over the top of a wing. Angle of attack didn't come into the picture until he explained stalls. When asked about how symmetrical airfoils worked, he was at a loss for words. Plus, I already knew from flying my hand out my mom's car window that angle of attack had a lot to do with creating lift. I think these new explanations are right on!
Harvey
Harvey
10-19-2013, 05:05 PM
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These videos are great! I remember back in college (never mind how far back that was!) when my professor was reciting the same, tired explanation of lift being entirely the result of faster air over the top of a wing. Angle of attack didn't come into the picture until he explained stalls. When asked about how symmetrical airfoils worked, he was at a loss for words. Plus, I already knew from flying my hand out my mom's car window that angle of attack had a lot to do with creating lift. I think these new explanations are right on!
Harvey
Harvey
When questioned on it.. the "play on words" reply was "Bernoulli sucks"
The CFI is retired now but has released a series of free e-books that are full of great information
http://www.flybetter.com.au/
Last edited by Rob2160; 10-19-2013 at 05:10 PM.
10-27-2013, 01:42 PM
#6
http://adamone.rchomepage.com/index5.htm
Any imaginable flying shape must have it:
http://www.geistware.com/rcmodeling/...calc/index.htm
