Friday 2010-09-03 Dev. update and Discussions

[dali]

Originally Posted by Flutter

Philip.ed:
The word you are looking for is wingtip vortices.

A wing creates lift by pushing air downwards. Behind the wing tip there is an interface between air that has been pushed down, and "untouched" air. This shear results in a vortex flow trailing behind the aircraft.
Flutter

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. On the pilot size debate > I would agree that the a) head is too small (we would need to see the whole body i.e. the 3d model of the pilot) or b) the team has used the lowest position of the seat (this happens when you have original drawings of the plane and some information are missing). I tend to go with the small head...here is the example. Please note, that the seat was adjustable for height, so we were always looking through the centre of the gunsight, which was actualy good old K-14 from the P-47 also used in Yugoslav air force.



on the scale debate - I would suspect that the roads have only one LOD, and that this is the problem (they seem to have same size regardless of the distance). I will stand corrected by Oleg or Luthier if I'm wrong.

EDIT - I did some quick check in the Corel Draw. I compared two known sizes, i.e. the head and the wheel. It seems that the head in SOW as it stands now is aprox 1/2 too small.



or closer





note> the lenght of the line is same on the head of the pilot and wheel on each individual shot.

[Ekar]

Originally Posted by dali

After seeing this, I reckon we need a black and white gfx option, preferably with nice film grain, for that extra historical 'realism'.

[AdMan]

if the scale in this:


and this:



look the same as this:


you need your eyes checked

[Flutter]

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