Blue Sky

My Feedback: (1)

Hi guys,
I'd be really grateful if someone could let me know how the wings on the 76" Lazy Ace (or any other similar sized bipe for that matter) are constructed. Specifically I'm interested in the spar material, thickness and arrangements, shear-web and wing sheeting thicknesses... I'm planning on building a scaled up version of a U.K. design which will take it to 72" span. I could buy the plans from RCM but what with the international shipping it gets a little expensive just for reference material

Any advice &/or tips would be much appreciated!
Thanks,
Blue

fokker20planes

I have in my hands the original construction article.

Spars: 1/4" square spruce Top and bottom. About 1/3 back from leading edge.
Spar: 1/4" X 1/2" spruce rear spar, bottom only. About 1/3 forward of trailing edge.
Shear webs: 3/16" vertical balsa. One side of 1/4" sq. spars only.
Wing sheeting: 3/32" sheeting top and bottom leading and trailing edge.
If you have any other questions just give me a holler.

w8ye

My Feedback: (16)

Wings front spar.. 1/4" sq spruce top and bottom

Wings secondary spar .. 1/4 X 1/2 spruce bottom only

Ribs 1/8"

3/32 balsa D-tube sheeting top and bottom of each wing from leading edge to over main spar.

Wing dihedral braces 3/16" birch ply goes out 2 panels each side

3/16" balsa vertical webbing full span on main spar only. Top and Bottom wing. Webbing is on front of spar

3/32" X 3" balsa sheeting top and bottom on trailing edge. No trailing edge strip.

Bottom wing only has ailerons. Trailing edge of wing and leading edge of ailerons in this area have 1/4" balsa. ailerons are covered with 3/32" sheet with no trailing edge strip.

Leading edge of wings 3/8 sq hard balsa on angle.

Tips are 1/4" sheet balsa.

Cut out in top wing for pilot is trimed with 1/4" balsa

Bottom wing dihedral 2 1/2" each tip

Top wing dihedral 1/4" each tip

No cap strips

Enjoy,

Jim

w8ye

My Feedback: (16)

The chord of the upper wing is 12".

The 3/32" leading edge sheeting is close to 4" to cover the spar.

The front spar is just ahead of the 4" from the leading edge point.

The rear sheeting is 3" wide.

The rear spar is located aft of the 8" from the leading edge point.

Enjoy,

Jim

Purple Pilot

Apologies, posted in wrong thread.

Blue Sky

My Feedback: (1)

Hi Tom, Hi Jim,
Very many thanks for all the great info Much appreciated!

If I can be really cheeky I have just one more question... would you happen to know the rib spacing, or the number of ribs per wing? As you can probably guess I'm trying to get an idea of the construction with respect to strength & rigidity.

All the best,
Blue

fokker20planes

I'll tell you what. E-mail me with your address and I will send you a photo copy of the whole article.
Ribs are 3" on center. 13 ribs per wing. This plane has a flat bottom airfoil.
The stab is airfoil shaped and has 12 ribs (flat bottom, 3/32 balsa) there are 2 ribs in the center about 1/2" apart. One main spar 1/4 X 1/2 spruce.
Let me know if you want a copy.

Blue Sky

My Feedback: (1)

Tom,
You are a gentleman and a scholar [sm=thumbup.gif]

Thanks for that additional info... I've cut the rib templates already and now I can draw the wing plan

BTW, I've e-mailed you (thru RCU) re. your very kind offer.

Many thanks,
Blue

leonmarks

Hi Tom, do u have the instruction manual for the lazy ace ?? I have a kit, but only have the plans.

That would be a tremendous help or even the artice you have.

Thanks
Leon