FLYBOYJ said:
Soren said:
FLYBOYJ said:
Soren said:
The P-51 was explained by its pilots as a pilots airplane, BUT, get into a stall with it "And your in deeeeep trouble !". The P-51's stalls were some of the most vicious of any fighter in WW2. (In the P-51's pilot's flight manual this is highly warned about)
The 109 on the other hand had a VERY forgiving stall, and it took 'much' longer to reach the stalling point aswell.
The Spit stalled better than both the -109 and -51.
British fairytale
The slats on the 109 made it much more forgiving in the stall than the Spitfire.
However the Spitfire did have good stall characteristics nontheless, because of the 2 degree twist (washout) of the wing tips that was needed for at least partially taming the nasty and violent stall behaviour of the elliptcal shape wing.
So the truth is that the Bf-109 had much better stall characteristics than the Spitfire.
Don't think so Soren - An Elliptical wing will ALWAYS give great advanced stall warning characteristcs. The Stall starts at the wing tips and moves inboard - exactly what is desired in any aircraft!
This is what was "Assumed" during the development of the elliptical wing, but sadly it was infact just theoretical, in reality it gave no difference. Besides automatic-slats has a much better effect on stall characteristics than a elliptical planform.
The elliptical planform has a very small theoretical advantage, but only theoretical, and only valid if the planform is truely elliptical. Spitfire's planform is only approximating elliptical, and what is left has been sold out by the aerodynamic twist it's wing has.
It has effect on just one of several factors of wing efficiency, causing a whopping 0.05 improvement in comparison to a trapezoidal planform used in for example Bf 109, that is, IF Spit's wing were truely elliptical...
You also have to take into account the fact that the profile thicknes ratio of Spit's wing is VERY thin, both in maximum and in average. This in turn leads to the small coefficient of lift. This pretty much takes away the advantage of the large wing area.
BTW, ever wondered where did all the elliptical wings go? If they are so magically efficient, why nobody uses them anymore?
The answer is simple, later aerodynamic research has proven that most of the benefits of elliptical wing were a fallacy created by insufficient or faulty research methods. They simply were not worth the trouble.
Even the developements of Spitfire, Spiteful and Seafang gave up on the elliptic planform and went to normal trapezoid form. Wonder why?
Only thing special in it is the elliptic planform, that dropped of favour just after it, when it was found out that the theoretical benefits of an elliptic planform were actually only theoretical, and practical applications did not yield benefits that would justify the almost astronomical manufacturing difficulties and costs.
In the Spitfire's case the benefits of elliptic planform (even lift distribution along the span) are nullified by the 2 degree twist (washout) that was needed for at least partially taming the nasty and violent stall behaviour of such wing.
Besides, wing aspect ratio has a much larger effect on the lift/drag characteristics than the Oswald efficiency factor (where the theoretical difference between Spit's and Bf 109's wing is only of magnitude of 0.05), and Bf 109's wing has higher aspect ratio than Spit's...