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Panthera

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  1. Bremspropeller, again you're forgetting that automatic slats don't start to deploy until around the 11 deg AoA, where the L/D is practically identical between the plain wing and the slatted one (the 109 uses a slat design that is about 1% deep), and from 10 deg AoA onward they're practically the same in drag. At ~15 deg AoA the plain wing stalls, whilst the slatted wing is starting to beat it in lift already at 12.5 deg AoA. In short no'one is arguing that fixed slots, like found on the Me163 for example, don't add "extra drag", but the automatic LE slats do not as they do not actu
  2. Well that's why I also included the latter, as it's for a 3D finite wing of a relevant AR, and thus a little more accurate. But again, the slats do not deploy until around 11 degrees AoA, so we're really focusing on irrelevant details at this point. Doesn't really matter as you've got one going the other way, also the adjustable lip should mean less radiator flap deflection is necessary for the same cooling effect, and thus less drag in that regard. Thus in the end I don't believe the 109's radiator design brought any negatives that the other designs didn't (MTT certainly
  3. Infact it's very close to the same even before that point, but that's the beauty of the automatic LE slats, they don't open until around the 11 deg AoA, where'as the above shows the graph for a constantly open slot. Can't say for sure without knowing the schedule of the system. But obviously it will add drag when it open, as did every other radiator design, Spitfire, P-51 etc.. So design wise I don't see it as a bummer compared to the rest.
  4. Speaking of the 109 (and other propjobs with a similar central tractor setup) that's the case in a power off/idle situation, like when coming in to land (this is why 109 pilots talk of the aircraft not dropping a wing and instead "sinking", with full lateral control retained, if stalled power off/idle in level flight), however in a power on situation propwash is energizing the inner section of the wing, locally raising the Clmax & as well as the critical AoA relative to free stream. As such adding slats, instead of wash-out, to the outer wing section allows this area to match the energized
  5. There is no "extra drag" added by automatic slats. Lift induced drag (Cdi) depends on lift required. In other words, more lift means more lift induced drag, however a lighter aircraft equals less lift needed* which in turn equals less lift induced drag generated. *Automatic leading edge slats will deploy and increase lift only when needed.
  6. Yes, pilot opinion is a tricky one, esp. if it comes from a source without lots of experience flying either of the aircraft compared. Hence why I tend to trust more in the assessments by modern pilots, as they're much better trained and also taught most of the aerodynamic principles at work. WW2 pilots by comparison had very little flight training and education in aerodynamic principles. That said, as you correctly point out the numbers/physical properties of the aircraft are the most important, as they give us an unbiased view as to how the aircraft should compare.
  7. Haven't had DCS for that long, but I've litterally only had positive experiences with their FM's so far (Got all the warbirds now, and a few fast movers). They probably also work off a bigger budget, considering the fidelity of their modules. That said I'm not just simply comparing the two sims and then going "that ones better" with nothing to back up the statement, I consider the DCS FM more realistic based on both pilot testimony and most importantly the actual physical specifications of the real aircraft. That said, I didn't really start getting this impression unti
  8. Those figures are not from the spec sheet though, they are tested values.
  9. Well the K4 in IL2 would need quite an increase it would seem, as it is beaten by the P-51 even at 67" Hg (added the G14 as well, which also oddly gained nothing despite being 150 kg lighter than the K4 with the same power): IL2 @ 370 km/h sea level: P-51D, 400 L, 67" Hg: 3.4 G's sustained 109K-4, 400 L, 1.8ata: 3.3 G's sustained 109G14, 400 L, 1.8ata: 3.3 G's sustained DCS for comparison: DCS @ 370 km/h sea level: P-51D, 400 L, 67" Hg: 3.0-3.1 G's sustained 109K-4, 400 L, 1.8ata: 3.6-3.7 G's sustained In short th
  10. I must say it doesn't take much skill to hold a level sustained load factor (you can even turn on automatic rudder if you're having issues holding the ball in the middle), and here the P-51 curiously comes off noticably better in IL2, which isn't realistic. In DCS it's the opposite way round, the K4 can sustain a significantly higher load factor than the P-51 here, as the aerodynamic specifications also suggest it should. IMO there can be little doubt which sim got it right in this case.
  11. Wing loading is more relevant to instantaneous performance, but it does help reduce the required lift coefficient, problem is the P-51 is much larger & heavier, and thus in the end it just isn't enough, and the difference in span loading squared indicates how much more thrust the P-51 will require to sustain the same load factor as the 109. Also I didn't cite wing loading as in this case we're talking two aircraft with no similarity in airfoil designs, with the 109's 2R1 profile (similar to NACA 5 digit series) having a noticably higher Clmax at the normal WW2 dogfighting speeds, where'as
  12. Well I'm struggling to find a western allied fighter that was lighter, and I don't remember mentioning the G6 or G14 anywhere. Also "maneuverability" is a broad term, so I'm not sure what you're refering to here either. If we're talking turn performance, are you aware that sustained turn performance relies on specific excess power?
  13. In reality everything speaks to the K4 being a stellar turn fighter, small, low weight, lots of power, very low span loading etc., and that is how it is simulated in for example DCS as well, where it easily beats for example the P-51 in any form of turning contest with the same fuel load in both (400L), as it should. In IL2 however it is curiously quite the opposite. I've brought up this issue earlier, where I tested the K4 against the P-51D in terms of sustained turn performance in IL2, and the K4 is soundly beaten here, which I can't see justified in any way from a physics/aerody
  14. Well unless I'm looking at the wrong engine power chart the difference in power was also usually over 15%, and as high as 35% at low altitude (below 5000 ft). Could it be you're looking at Sabre IIA power curves and not Sabre IIB ones? AFAIK the IIB gained a power boost over the IIA at all altitudes. Also let's not forget that in games such as these most fights take place below 5,000 ft to begin with, and if not they usually end up there in the end.
  15. I don't think it should turn worse than the P-51D, which is heavier than the P-51B and has the same power. That said above 15 kft I'd say the P-51 probably generally had the advantage over the Tempest.
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