Leading Edge Slats on the Me-109

[TomcatViP]

Humm forgot the wing surface above. As it is a cte in the relation V=f(alpha) there is no impact on the overall result.

And it seems I was way too short in my explanation abt the revolution in aero theo in 35. For one time NZ, don't bounce me too hard on tht one

[Robo.]

Originally Posted by TomcatViP

-Slats are deployed in front of the ailerons in order to keep ctrl at stall conditions. No wing drop (and full airflow around the pouter portion of teh wing), no asymmetric stall . Hence no spin. This is why Crumpp refer it as an anti-spin device. So Crumpp was right (again...)

Wurster slowed down, pushing back the throttle to idle. As the Bf 109V2 slowed, the automatic leading-edge slats deployed and the warning horn sounded in the cockpit. The controls gently shuddered. The plane was now on the edge of a stall. With both the rudder and ailerons ineffective, the control stick going forward towards the instrument panel, he pushed the nose about ten degrees below the horizon. The left wing dropped and the aeroplane went into a spin. (...)

[TomcatViP]

Originally Posted by Robo.

Wurster slowed down, pushing back the throttle to idle. As the Bf 109V2 slowed, the automatic leading-edge slats deployed and the warning horn sounded in the cockpit. The controls gently shuddered. The plane was now on the edge of a stall. With both the rudder and ailerons ineffective, the control stick going forward towards the instrument panel, he pushed the nose about ten degrees below the horizon. The left wing dropped and the aeroplane went into a spin. (...)

V2!

[Robo.]

Originally Posted by TomcatViP

V2!

Same wing, same slats.

[Crumpp]

Bf-109V2

Excellent story....

Might want to do some background research on the design.

[Crumpp]

Same wing, same slats

Nope....

[Robo.]

Originally Posted by Crumpp

Nope....

I am not saying 'identical', I am aware of the small differences of earlier and even later models but the slats are slats - they do have same function and effect, have they not? Were the early 109s V-2 including not 'spin-resistant' even when they had the (same) slats?

Comparsion of the V-2 and E-3 wings:

[Glider]

Originally Posted by Crumpp

Excellent story....

Might want to do some background research on the design.

Crumpp
What do you tell your students about leading edge slots? Do you tell them:-

a) That they are devices that delay the stall or
b) That they are anti spin devices

Just wondering

[fruitbat]

Originally Posted by Robo.

I am not saying 'identical', I am aware of the small differences of earlier and even later models but the slats are slats - they do have same function and effect, have they not? Were the early 109s V-2 including not 'spin-resistant' even when they had the (same) slats?

Comparsion of the V-2 and E-3 wings:

Its funny isn't it, when they're arguing about the wings the V2 is different beyond all measure to the E3, but when they were talking about the top speeds, they were identical.

[taildraggernut]

Originally Posted by TomcatViP

Regarding the 109:

-Slats are deployed in front of the ailerons in order to keep ctrl at stall conditions. No wing drop (and full airflow around the pouter portion of teh wing), no asymmetric stall . Hence no spin. This is why Crumpp refer it as an anti-spin device. So Crumpp was right (again...)

Then why is washout not automatically considered an anti-spin device? it has exactly the same function, to prevent the outer portions of the wing from stalling and maintain aileron effectiveness during the stall and prevent assymetrical stall, if you do consider washout an anti-spin device then what makes it inferior to slats?

so why is it that 2 aircraft with 2 solutions to the same problem (Spit/109) apparently have totally different behaviours? is it really because of the elevator design on the 109 which prevented the use of pitch at stalling angles? or perhaps the design was too stable (see RAE report) which meant there was not enough elevator authority?
either way it seems you get 2 choices here, either the 109 was able to turn well (and possibly suffer a spin if overdone) or you have limited elevator authority which impedes manouverability.