Another speculative thread - adding forward sweep to solve CG problems

[TFF]

True issue or best practices? The DH folding wing mounts are still used yet you can’t fold the wings on the Tiggie. Charming it got away with it all. Not death to design but better is always better.

 

[Chilton]

I think it would be a stroke of luck if any rib on a fabric covered wing was truly parallel with the local airflow once you consider inflow over the wing, outflow beneath it, interference around struts and the fuselage, propeller slipstream, etc. In any case, the Tiger Moth has all its ribs at 90° to the (swept) spars and it doesn’t seem to be an issue.

There has been a Tiger Moth built with the ribs parallel to the aircraft centre line, it showed a slight improvement in performance compared to the standard wing. The builder was initially puzled by the performance of the Tiger compared to the Moth Major and so set out to investigate. Apparently the angled ribs do increase drag. It was written up in the Moth Club magazine many years ago, so if I find the article I will post it but that may take some time!

 

[rmeyers]

Piper Comanche has forward swept wings.

 

[Bill-Higdon]

Piper Comanche has forward swept wings.

Along with the Mooney

 

[Tiger Tim]

There has been a Tiger Moth built with the ribs parallel to the aircraft centre line, it showed a slight improvement in performance compared to the standard wing.

I’m not really surprised that it showed some improvement, I guess my point was that the plane will still fly Andy probably not be weird to handle. I haven’t flown a Stampe or a Jungmann (yet) but I’d like to give them a go for comparison’s sake against the Tiger Moth. I hear they’re better flying but to be fair they weren’t the end result of twenty years of compromises either.

 

[BJC]

Piper Comanche has forward swept wings.

Along with the Mooney

Since the primary aero effects of sweep are a function of the leading edge sweep angle, I define a swept wing as one whose leading edge is at an angle other than 90 degrees to the fuselage axis.

BJC