Aerodynamic manoeuvres and Wing rakes


Ok I am most likely entirely off base here. But, with fly by wire technology perfected (see the purposely unstable euro fighter typhoon) why not use forward swept wings and also invert them so they are upside down to normal wings. Wouldn’t this give better lift/better speeds and more manoeuvrability with fly by wire tech?

We know that inverting wings gives better lift and that we have more manoeuvrability with forward swept wings, see the Russian SU47 for just that capability.

Add in the anti radar tech from the F22 and surely that’s a better fighter all around isn’t it? Or did I, most likely make a mess of understanding the tech?

Thank you

In: Technology

Can you explain your question like I’m five?

I’m not sure what you mean by inverting the wings but forward-swept wings need to be stronger (and therefore heavier) than straight or rearward swept wings and, when it comes to building aircraft, weight is a pretty big factor to consider. Yes, it makes the plane more maneuverable but the benefit isn’t really worth the weight penalty.

Also, for modern fighters, more emphasis is being placed increasing the plane’s stealth characteristics so maneuverability has taken a bit of a backseat.

> why not use forward swept wings

NASA did build a research plane to study forward swept wings, the X-29.

While the wings do help with maneuverability the wing-tips are subject to extreme torsional stress. That stress can cause wing-tip flutter, leading to loss of control, and even structural failure. Building a wing stiff enough to prevent flutter adds significant weight, offsetting any advantage.

Note that the Su-47 was a test bed, only one was built, not a production aircraft. A big issue with looking at Russian (and old Soviet) equipment is that the Russians are completely paranoid when it comes to releasing any information about how they actually worked. In this case I think we can assume that since the Su-47 wing configuration did not appear on subsequent Russian designs that it didn’t give them the results they were looking for.

Finally, the tendency has been lately to put less emphasis on airframe maneuverability and more towards stealth, avionics and missile performance. Part of that is because airframes have been capable of more maneuverability than the pilot can handle for decades now. The other part is that that extra maneuverability is of no value if your plane can be downed by a missile you didn’t see coming launched from a plane you didn’t know was there.

I’m really not aware of any testing on inverted-wing designs. Again, with the amount of testing that NASA and others do, it’s almost certainly because the adavantages are offset by the disadvantages.