Is there a cheapest/lightest/simplest wing structure other than aluminium tube and fabric?

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Wespa

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Apr 9, 2022
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Do the math on the internal volume of said wing filled with helium and you'll find that it's only 4.5 pounds lighter than if filled with air and that ignores the volume of any structure in the wing. I'll let you do the math on the fuselage volume and resultant weight decrease and then you can decide if it's worth your while or not
Hydrgen it is then.
Problem is helium leakage, Helium is Mother Natures Houdini which is why it's used for leak checking
Yes. I've read about it. Hardto contain.
 

Sraight'nlevel

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Heavy! A 4.5' x 22' wing will have 100 lbs in it before the plywood skin and any structure, hinges, spar caps, etc.
How about using white 16 kg/m3 foam....and bond 1 mm thick plywood into those foam formers 2 cm thick and spaced 300 mm behind the spar and 150 mm spaced before it ? Then apply silk or mylar on the trailing part and full 1 mm plywood on the leading side+ thin class fiber and strips of carbon a top on the spar area...spar being made of 5 mm thick veneers of hard wood...so that root has "solid" wood and tips only one ply....caps 3 mm plywood ( birch ).
 

poormansairforce

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How about using white 16 kg/m3 foam....and bond 1 mm thick plywood into those foam formers 2 cm thick and spaced 300 mm behind the spar and 150 mm spaced before it ? Then apply silk or mylar on the trailing part and full 1 mm plywood on the leading side+ thin class fiber and strips of carbon a top on the spar area...spar being made of 5 mm thick veneers of hard wood...so that root has "solid" wood and tips only one ply....caps 3 mm plywood ( birch ).
The white foam I am familiar was the has no tensile strength so no for me.
 

Aesquire

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Hydrogen is even worse than Helium for slipping through what seems a solid.

Slow flight? You still need to resist gravity.

The lightest wings now flying are made of cloth. Very fancy, strong, cloth. Shaped & sewn so the air flow provides support, with synthetic strings to the load. Paragliders. It's a fairly mature technology today, still in progress.


But if pressurized tech is your thing...



The LEI, ( leading edge inflatable ) technologies could be adapted to flying without the long lines of a paraglider, and a few kilos of carbon fiber in struts combined with intelligent power/pilot pod...


Don't let the apparent simplicity fool you. There's a lot of thought and product development.

All in all it's hard to beat aluminum tubing for ease of home manufacturing. It's technology and tooling easy to learn and cheap to purchase. I built 2 hang gliders in a garage with a portable drill and hand tools. Contracted out sewing to pros. That's it's own skill set.
 

jedi

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Sahuarita Arizona, Renton Washington, USA
Design for cheep/light/easy construction is dependent on wing loading and size.

P 51 and indoor endurance free flight model will never use similar construction methods.

How many here are interested in 32 foot span, 100 sq ft 300 pound max gross weight 3 G wing?
 

rotax618

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Oct 31, 2005
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Evans Head Australia
You wouldn’t use expanded foam for anything but a core, even then it has an inferior compressive strength/weight than extruded polystyrene. The CFM Shadow used a D box leading edge, which consisted of ply covered blue foam ribs, the rear ribs were glass covered blue foam. The wing was cantilever, except for short struts to stabilise the wing-fuse attatchment.
EE2ACFEA-61A5-41C3-BEF5-722FD9F2017F.jpeg
 

Bill-Higdon

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Feb 6, 2011
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Salem, Oregon, USA
Hydrogen is even worse than Helium for slipping through what seems a solid.

Slow flight? You still need to resist gravity.

The lightest wings now flying are made of cloth. Very fancy, strong, cloth. Shaped & sewn so the air flow provides support, with synthetic strings to the load. Paragliders. It's a fairly mature technology today, still in progress.


But if pressurized tech is your thing...



The LEI, ( leading edge inflatable ) technologies could be adapted to flying without the long lines of a paraglider, and a few kilos of carbon fiber in struts combined with intelligent power/pilot pod...


Don't let the apparent simplicity fool you. There's a lot of thought and product development.

All in all it's hard to beat aluminum tubing for ease of home manufacturing. It's technology and tooling easy to learn and cheap to purchase. I built 2 hang gliders in a garage with a portable drill and hand tools. Contracted out sewing to pros. That's it's own skill set.
Hydrogen lift has an additional issue of oxygen leaking in & causing a BIG KABOOM if the O2 content gets too high and no easy/good way to separate the O2 from the H2 with out "the earth shattering Kaboom"
 
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