dali wrote: actualy lift is created by air being forced to flow over two different distances. since all things in nature which were disturbed in their original flow try to restore order and harmony, this is also valid for air > thus air from lower part of the wing, which has higher pressure wants to balance with air on the upper surface which has lower pressure > and so creating lift force. since the wing is not indefinite, but very finite plane, air from bellow and above do meet in one point, and this point is of course the wingtip. The drag produced is called induced drag, and there are some vortices, but their force depends on weight. In airplane of such relatively small size the vortice is so weak, that it is almost non existant.
Yep.
I know how this works. My daytime job is designing these damned things. The end result of the process you describe is air being pushed down.
Where I disagree with you is with regards to Vortice strength. Vortice strength is dependent on airspeed, wing loading (weight per area), aspect ratio (wingspan squared over wing area) and the shape of your span-wise lift distribution (preferred to be elliptical). A WW2 fighter has small and stubby wings, is relatively heavy (especially the german designs), and would pull substantial g loads. The vortex trail could be substantial.
on the other hand, a spit with no more ammo and empty tanks flying at full speed in a parabola (zero g) heading for terra firma would indeed have a "vortice is so weak, that it is almost non existent"
Flutter
PS: since Oleg and team are actually calculating the traces of single bullets, it would actually surprise me if every aircraft will NOT leave a mathematical wake containing wingtip vortices and propwash
|