F6F, FG-1, P-51, P-47 comparison

[Cthulhu]

Well, another interesting thing: Laminar flow airfoils are known for stalling all at once, so the P-51 stall does not surprise me. However, I've had people who have actual P-51 stick time tell me the onset of the stall is quite apparent. Curious.

Ditto. I had a professor back in college who was a pony driver during the war. He said the P-51's stall could be downright treacherous with little to no warning at all. I recall him describing the CL- alpha curve as a straight line with a slight wobble at the top followed by a vertical nose dive.

[Krusty]

From other comments I've read, the P-51 was intended to have laminar flow, but didn't really come close to it. It was a good wing, just not laminar flow. Might explain why the supposed laminar flow didn't stall like a laminar flow should (because it wasn't).

[Krusty]

The difference in directional stability of the P-51B and D is extremely noticeable--I can discern a huge difference.  Try flying with combat trim off and note how differently they behave.

I do, and I notice no difference. You can yank and bank pretty easily. Back before AH2 came out even with CT on you spun out in a 51D a lot easier. Pull too hard and you spin into your inner wing. No longer happens. Might dip a wing here or there, sure it snap stalls, but the model is incomplete, it seems.

[Stoney]

I recall him describing the CL- alpha curve as a straight line with a slight wobble at the top followed by a vertical nose dive.

That's pretty typical for a NACA 6-series airfoil.  If you've ever flown a plane with an airfoil like this, one minute you're flying, the next minute, you're not.  Basically the way NACA computed the coordinates, they unintentionally decambered the leading edge of the airfoil shapes, meaning a very sharp loss of lift at the stall.  Several of the laminar airfoils developed since have solved this.

There's still a warning, its just very, very quick--and not the same type of burble warning you get with a turbulent airfoil.  If you're riding the edge of the stall, you can feel it, but the transition is so abrupt that if you ham-fist the stall like you would on a plane with a turbulent airfoil, you go abruptly from flight to stalled.

[BnZs]

From other comments I've read, the P-51 was intended to have laminar flow, but didn't really come close to it. It was a good wing, just not laminar flow. Might explain why the supposed laminar flow didn't stall like a laminar flow should (because it wasn't).

I'm inclined to think the simplest solution to the discrepancy is variation in the ability of pilots to detect the subtle warning of the stall.

And from what I understand, every plane is harder to stall/spin since AHII came out.

(I notice you are not very vocal in demanding more vicious 190 departure behavior or that HTC change the modeling so that asymmetrical slat deployment becomes possible in the 109s there Krusty)  

[Stoney]

I do, and I notice no difference. You can yank and bank pretty easily. Back before AH2 came out even with CT on you spun out in a 51D a lot easier.

Directional stability is a matter of yaw stability.  The D-Pony's nose wanders all over the place in game, whereas the B-Pony is conspicuously more stable.  I'm not talking about its tendency to spin when stalled.

but the model is incomplete, it seems.

Or fixed.

[Old Sport]

Just curious - during the tests were the planes loaded to their typical WWII operational weights? (Guns, ammo, armor, self-sealing tanks, old heavy radios - would add weight.)

Regards.

[colmbo]

Don't be naive.  Anytime you start testing stalls in these WW2 aircraft below 10k you risk the airframe.  That's a fact. 

Oh BS!  Geez, I've done stalls in a Mustang as a 500 hour Cessna pilot.   We were never higher than 7500', plenty of warning, no drama.

[Stoney]

D or H model?

[bozon]

The P47 really comes out as a pleasant ride in this test.

[SectorNine50]

I'm assuming pilots that flew the P-51 a lot knew right about where it was going to stall based on feel, and therefor felt that it had plenty of warning (as apposed to this tester who probably didn't fly it every day like the WWII pilots did).  When you use a machine often enough, being "one with the machine" quite literally does happen.  You can even notice it while driving a car, you can tell without any obvious audio or visual warning that a car's tires are at their limits when in turn, stopping, accelerating, etc.

I actually believe that is why the P-51 is so hard to get kills in as a new player, it really is just one of those planes you have to get to know before you become effective in it.

I really would like to know what the load-out of these aircraft were at the time of the test because the P-47's results really doesn't seem to fit how it flies in-game.

Asymmetrical slat deployment would be an nice addition to the game, would be interesting to see how it changes the characteristics of the aircraft that have them and if it gives any insight to how the aircraft really reacted in real life.

[Anaxogoras]

Asymmetrical slat deployment would be an nice addition to the game, would be interesting to see how it changes the characteristics of the aircraft that have them and if it gives any insight to how the aircraft really reacted in real life.

I guess you don't fly aircraft with leading edge slats.

[Golfer]

Asymmetrical slat deployment would be an nice addition to the game, would be interesting to see how it changes the characteristics of the aircraft that have them and if it gives any insight to how the aircraft really reacted in real life.

We have that now.  The slats on each wing operate independent of one another however due to the nature of their design they'll operate nearly simultaneously when the required angle of attack for them to deploy is reached on each wing.

[BnZs]

We have that now.  The slats on each wing operate independent of one another however due to the nature of their design they'll operate nearly simultaneously when the required angle of attack for them to deploy is reached on each wing.

I have been unable to cause an asymmetrical deployment, and I've tried hard. Got film of one occuring?

[Anaxogoras]

BnZs, how often do you fly the 109?