Hombebuilt B-29/Stratocruiser

HomeBuiltAirplanes.com

Help Support HomeBuiltAirplanes.com:

Workhorse

Well-Known Member
Joined
Mar 6, 2010
Messages
400
Location
Southern Spain
Hi wonderous. I'm employing douglas fir because it is what my local authority is happy with. But in fact the main loads are carried by the gl1 plywood. I think fir more than structural is a good core which holds everything together. The wood take the main loads and stay stiff meanwhile the fiberglass takes the twisting loads.

Here is a root chord cutaway with no fiberglass depicted.

Marty, those are the toys I'd like to have.
 

Attachments

Last edited:

WonderousMountain

Well-Known Member
Joined
Apr 10, 2010
Messages
1,853
Location
Clatsop, Or
I built houses. Just looked up what Gl1 plywood is. As a filler dougless is fine.

It amazes me how light you are able to get these small planes. In houses, we're always cutting costs, but never worrying about weight unless it costs more. It's great to see the way others adress the challenges of small aircraft. I hope when it comes time for me to start, there will be a wealth of knowledge I can draw from.

Blessings,

Wonderous Mountain
 

Workhorse

Well-Known Member
Joined
Mar 6, 2010
Messages
400
Location
Southern Spain
The mecanism is borrowed from Mr. Strojnik's books. It is the same upper wing sking acting as a hinge.

Wonderous, this project is also an experiment to see how cheap can an aircraft be built.

On the other hand I would like to ask our Admin to close this thread since its content have no longer anything to do with the title.

Thanks.
 

JimCovington

Well-Known Member
Joined
Mar 30, 2009
Messages
217
Location
Burlington, VT
On the other hand I would like to ask our Admin to close this thread since its content have no longer anything to do with the title.

Sheesh, don't do that. If we shut down every thread when it diverged, we wouldn't have a forum left. :gig:

Can you imagine hangar flying at the local strip and having to stop talking every time someone said "Hey, that reminds me..." :roll:
 

BDD

Well-Known Member
Joined
Apr 2, 2005
Messages
388
Location
WI
Have you checked the elasticity modulus of wood compared to the fiberglass. I expect they'll be a lot different, and either the wood or the skin will end up carrying almost the entire load.

Also, Douglass fir is not my idea of a good aircraft wood. It's usually readily available and easily worked though.

Actually, this is one of the better propositions I've seen here so far.

Looks good.

Wonderous Mountain
Actually, properly graded Douglas Fir is an excellent material for aircraft structures. It is stronger than spruce in bending stresses, etc. and is more economical. The only drawback is that it is also denser. If used, your airplane will probably weigh more, then again, you don't need quite so much of it because of it's strength ptoperties. That would slightly offset it's increased density. It would be very good for wooden sparcaps. He should consider carbon fiber spar caps though.

What would be a good source with information on designing moment and shear resistant joint connections for a wing with carbon fiber sparcaps? I'm thinking of a plywood or aluminum spar web for shear loads with carbon fiber spar caps. I'm also interested in how they should be lapped if you can't get them the full length of your wing spar and how they are built up to accommodate bolted moment connections.
 
Top