150hp Super Cub Wing

[jherbert]

A friend and I are both scratch building Super Cub replicas in South Africa. We have almost completed fuselages and we are now looking to start the wings.

We have a complete (or almost) complete set of original Piper plans. In researching the wing, I discovered that I have plans for the wing spars for the 95hp to 135hp Super Cubs. (part nos. 14383-04, front spar, and 14453-04, rear). The spar design seems to be different for the 135 and 150hp Cubs as the part numbers differ. They are 14391-02 ns 14392-02, but I don't have the drawings for this part number.

I am under the impression that the spar extrusion used is exactly the same for all metal spar pipers from J3 to PA25, but I would like to find the information abou the difference in design.

John Herbert.

 

[S2D]

All major holes are the same. only difference is the little holes for attaching the ribs and leading & trailing edge skins. You will probably want to custom fit those anyway. ( I am assuming your drawings have the holes for the flap brackets and bellcrank. the 95 doesn't have them.)

 

[Frank T]

John

The spars on the early and later PA-18 are the same dimensions, sizes and material. All the spar attach fittings, strut fittings, drag struts, aileron hinges, etc. are all in the same locations on both. The earlier wings had 13 ribs and the later 16 ribs (just different spacing). All the 16 rib wings came with flaps. Most of the 13 rib wings came without flaps, although you can also put flaps on the 13 rib wing.

You should be able to get a print for the 16 rib wing from the Cub Club or Univair. The North Land CD has the wing drawings on it, but the Spar drawings on it are also for the 13 rib wing, so if you build the 16 rib wing you need to adjust the rib spacing before drilling the spar flanges for the ribs.

Both wings are about equal in strength, and both can use the Wipaire 2000# Gross Weight STC. The 13 rib wing has a lower max operating speed, because of the leading edge not being as ridged (wider spaced ribs).

Frank

 

[jherbert]

Thanks guys for the information. I am using the North Land CD, but we are now trying to locate the drawings for the 16 rib wing.

 

[diggler]

delete

 

[Frank T]

The North Land CD does have a print for the 16 rib wing (#14394). Both the original North Land CD and the newer revised addition both contain the original Piper 14394 drawing. On the revised CD North Land has a copy of a wing drawing they got from Dakota Cub (nice clean auto cad drawing). This is the default drawing that comes up when you open 14394, however, there is a link on this drawing to the original Piper 14394 Drawing. Be advised that the spacing shown between the flap hinges on the Dakota wing drawing is WRONG. It is shown as 42" and should be 44".

Frank