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SgtPappy 01-01-2010 07:12 PM

Indeed, the slats on 109 wings were able to make the aircraft turn better according to the Germans, and planes like the La-5 and La-7 have them, but I've never noticed them in-game. The cause for the better turning ability is that the slats (according to the diagram below) seem to cause a Bernoulli effect, pressurizing and speeding up the air over the wing. This delays separation of airflow and maintains lift at higher AoA.

http://www.virtualpilots.fi/feature/...ENVAIKUTUS.JPG
http://www.hyperscale.com/images/006.jpg

I don't know why others haven't noticed before, but I've mentioned it a couple of times as well, kozzm0. :-P There's a lot of error in speed and acceleration; a major problem in an energy fight. Like you said the Yakovlev should pass 700 km/h in level flight, and my Spitfire IX should easily pass 320 mph @ SL. I can't even pass 305 mph. Our inability to accelerate from slower, lower-powered foes makes it nigh impossible to truly energy fight since energy fighters generally have the ability to gain energy faster than their opponents. Since there is no such advantage in BoP, there is nearly no way to really energy fight. Simply we can only extend, climb and BnZ slower aircraft rather than gaining angles on them using superior speed gained from faster acceleration.

kozzm0 01-02-2010 10:13 AM

So the slats enable the wing to add lift without increasing drag? Or to increase AOA without increasing drag?

I had thought of them as just being a way to add area to the wing to decrease loading, but the air flowing through the slots has something to do with it too then.

Soviet Ace 01-02-2010 10:58 AM

If I could just coin in on this little Kozzom0 and SgtPappy conversation. The Yak-3 in which you're both talking about that has a 708km/h speed is the post WW2 Yak-3 that was powered with the unreliable VK-107 or the Western name: M-107. ALL Yak-3s in WW2, were powered with the reliable VK-105PF-2 which put out about 650-655 km/h or so. The VK-107 engine that Klimov created came out too late for WW2, and was originally intended for the Yak-3U, but was put in afterwards which was later taken out because of its unreliability.

So keep to the WW2 Yak-3 which had a VK-105PF-2, not a VK-107. :D Thought I'd correct that. ;)


EDIT: Oh and I forgot to mention, there is no such thing in Soviet history or anywhere of the "VK-1097PF-2" engine. So wikipedia (incase you're interested at all) is wrong on calling it the VK-107PF-2. Specially when they're talking not about a Yak-3U or anything, but just the original Yak-3 (The basic simple one that I personally prefer) which had a real world Soviet VK-105PF-2. No where in my books on Yaks, is there a mention of a VK-107PF-2 engine or anything.

kozzm0 01-02-2010 03:09 PM

Quote:

Originally Posted by Soviet Ace (Post 132748)
EDIT: Oh and I forgot to mention, there is no such thing in Soviet history or anywhere of the "VK-1097PF-2" engine. So wikipedia (incase you're interested at all) is wrong on calling it the VK-107PF-2. Specially when they're talking not about a Yak-3U or anything, but just the original Yak-3 (The basic simple one that I personally prefer) which had a real world Soviet VK-105PF-2. No where in my books on Yaks, is there a mention of a VK-107PF-2 engine or anything.

I could have spent my whole life believing in the vk-107pf-2 engine, if I had ever heard of it. Now if anyone ever says "vk-107pf-2 engine" I will know they're full of crap

Maybe you should fix the wikipedia, the fix will stick since you've got a reference

Ok so the ww2 yak-3 could only do 650... but I can't hit 650 in BOP either. Seems to top out at about 550 for me. Low altitude, of course, could it go faster higher up? I've looked at e/m charts but not altitude performance charts

Soviet Ace 01-02-2010 03:29 PM

Quote:

Originally Posted by kozzm0 (Post 132788)
I could have spent my whole life believing in the vk-107pf-2 engine, if I had ever heard of it. Now if anyone ever says "vk-107pf-2 engine" I will know they're full of crap

Maybe you should fix the wikipedia, the fix will stick since you've got a reference

Ok so the ww2 yak-3 could only do 650... but I can't hit 650 in BOP either. Seems to top out at about 550 for me. Low altitude, of course, could it go faster higher up? I've looked at e/m charts but not altitude performance charts

Right, the WW2 Yak-3 did 650 km/h, and later could do about 708 km/h with the VK-107. The WW2 Yak-3 best performance at high altitude, was maxed 10,300ft or so. The VK-105PF-2 wasn't much for high altitudes, and could freeze up if at certain altitudes. (More like B-17 altitude etc. I would guess.) Its max ceiling was like 35,000ft but it performed terribly due to its wingspan and all around small body etc. Anyway, I would try it around 10,300ft and see what you get. From my books; that was the Yak-3's best high altitude performance range, and anything higher would probably get the Yak-3 into trouble. Farther down, like sea level down, I'm sure you could get some pretty good speed from the VK-105PF-2, but I haven't tested it myself on BoP. I think the Yak-3 along with all the other planes are a bit inaccurate here and there.

For example, the Yak-3 did not have a ring like the early Yak-1, 7, 9's did.

Picture of a REAL Yak-3 cockpit, everything where it should be. The picture is also in my books, but I found it online so it was easier. :D
http://www.pilotfriend.com/photo_albums/images15/17.jpg

SgtPappy 01-02-2010 05:59 PM

Thanks Ace, it's good that you arrived when you did. Though you have proven our figures wrong, I think the three of us can agree that our BoP planes are much too slow at least at sea level.

The Spitfire IX in-game has a larger rudder, suggesting it's a late-built model, most of which were equipped with the Merlin 66 engine. Spitfire LF IX (one's with the Merlin 66) could usually pass 330 mph at sea level. You'll notice that isn't anywhere near possible in BoP. If our Mk.IX is indeed modeled after the first Mk.IX's that entered service with the Merlin 61 in 1942, I should still have little problem passing at the VERY least 310 mph without WEP, which again, does not happen. Of course, since all the planes are a little too slow, that shouldnt be much of a problem. The problem arises when the Hurricane behind you reaches 200 mph the same time as your Spitfire IX when you both started at 170 mph. :evil: Acceleration is a very important advantage that some fighters have over others that simply allows for a domnant energy fight.

kozzm0, Lift cannot be produced without drag. When the slats are deployed, they do indeed produce much drag, but that's not a problem when you're pulling alpha trying to out turn someone.

kozzm0 01-03-2010 12:12 PM

I know there has to be drag... I was thinking about how the slats improve performance by "delaying airflow separation," it seems like that would also decrease the difference in pressure on the leading edge. Anyhow they worked, I guess

you've been drafted by team USSR, btw... check the battle for europe thread

Recently I was training with an la7 and my engine was hit so I headed back to land at 55% power... and noticed I was doing over 600. No lack of power in that model.

Soviet Ace 01-03-2010 06:10 PM

Quote:

Originally Posted by kozzm0 (Post 132788)
Maybe you should fix the wikipedia, the fix will stick since you've got a reference

And let it be said, that I did so. The Yak-3 specifications on Wikipedia, are now 100% accurate for the WW2 Yak-3. :D


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